Can We Travel To That Exciting New Exoplanet?

An anonymous reader writes "The news last week that exoplanet Gliese 581g may be in the 'Goldilocks zone' and could therefore hold liquid water and alien life got everyone all excited, with good reason. A potentially habitable planet — and only 20 light years away! But to put things in perspective, here are a couple of estimates on what it would take to travel to Gliese 581g. One scientist puts the travel time at 180,000 years based on current space flight technology, while another explains that it could be quite quick if we build a matter-antimatter drive, and can figure out how to bring along 530 times as much mass in fuel as is contained in the ship and cargo itself."

Comments

180,000 years

[Anonymous Coward]

180,000 years? Well, what are we waiting for?! Time's a wastin'!

Re:180,000 years

[D3]

Assuming it takes 100 years to build everything we need to make this flight, by the time you get there it will be 178,570 years after the group that took 1000 years to build the matter/antimatter ship finished their project.

Re:180,000 years

[Anonymous Coward]

The problem of when to embark on such a trip seems like it will be very similar to the problem of when is the best time to start brute-forcing a decryption process. The answer to both will likely be never. In both cases, using tomorrow's technology will complete the task sooner than using what's available today.

Re:180,000 years

[The Archon V2.0]

Assuming it takes 100 years to build everything we need to make this flight, by the time you get there it will be 178,570 years after the group that took 1000 years to build the matter/antimatter ship finished their project.

This is what I see happening: The first colony ships will leave for a newly-found planet using then-state-of-the-art technology and when they arrive the first thing they'll see is a McDonald's putting up a sign advertising their new "Colonist Combo Meal Deal".

Re:180,000 years

[dave420]

I think it'll be a bit different. The colony ships will take off, and slowly build up to something approaching c over a great length of time. Thanks to special relativity, the faster they go the faster time is passing on Earth (relative to them). That means soon after they set off, relatively speaking (no pun intended) they'll be intercepted by FTL craft from Earth. Obviously we might not make FTL craft, but if we ever do, all those who left Earth before they were built will be picked up along the way by one. If I was on an interstellar ship, and arrived at my destination unmolested by human kind, I'd start worrying.

Re:180,000 years

[kevinNCSU]

What's the benefit of stopping to pick them up when you can instead be the very first people to the new planet and get to place your armies in Australia?

Re:180,000 years

[Zenaku]

Thanks to special relativity, the faster they go the faster time is passing on Earth (relative to them).

That's exactly backwards. Thanks to special relativity, the faster they go, the slower time is passing on earth relative to them. And vice-versa. Time is passing slower for earth relative to them, and slower for them relative to earth. The colony ship would only find themselves to have experienced less time than what had passed on earth if they decided to turn around and come back.

http://en.wikipedia.org/wiki/Twin_paradox

Re:180,000 years

[dpilot]

As long as you're into science fiction...

Your scenario is described in "Songs of Distant Earth" by Arthur C Clarke. In that book, the root of the solar neutrino problem was that the Sun was burning out. Light from the core takes 1000 years to get to the surface, but neutrinos get out practically immediately. The information that the hydrogen-burning life of the Sun was over hadn't made it to the surface yet. So we figured it out, and realized that we had some 900 years (Evidently the solar neutrino problem had barely started when we discovered it.) to find a new home. Interstellar travel became a top priority very quickly. First ships were slower, later ships were faster. The story takes place when an earlier ship stops over at a planet which had already been colonized by a later ship.

Or take "Hitchhiker's Guide" by Douglas Adams or "Those Gentle Voices" by George Alec Effinger. Put all of your non-productive people on the first slow ships. Then those that are left can work faster/better on newer, faster ships. In a twist, safe flight for the first slow ships is optional, as are intentional crashes.

Re:180,000 years

[Tablizer]

This is what I see happening: The first colony ships will leave for a newly-found planet using then-state-of-the-art technology and when they arrive the first thing they'll see is a McDonald's putting up a sign advertising their new "Colonist Combo Meal Deal".

That's kinda what PC's are like: you boot up your shiny new 64-bit PC, and the first thing you see in its browser is an ad for the 128-bit 3D model.
   

Re:180,000 years

[pixelpusher220]

That's exactly backwards. Thanks to special relativity, the faster they go, the slower time is passing on earth relative to them.

No you have it backwards. As they approach c their time slows down so that c stays c. Meanwhile on earth time is moving along at 'normal' rates which is much faster than on the ship that is going near c.

The colony ship would only find themselves to have experienced less time than what had passed on earth if they decided to turn around and come back.

Yes because all relativity effects are only felt on the way back. Facepalm. perhaps you meant they would only realize (as in see it firsthand) the time difference when they returned to earth, but they have indeed experienced less time regardless of whether they go back or not.

Re:180,000 years

[blind biker]

Read Mayflower II, an award-winning, excellent short novel by Stephen Baxter, probably the best contemporary hard Sci-Vi writer. The topic is, indeed a generation ship (one where multiple generations have to pass before the destination is reached). It's absolutely perfectly and vigorously on topic for this entire thread and your post in particular.

Re:180,000 years

[Zenaku]

Listen, this stuff is not easy to articulate, so I will grant that I may not be saying it clearly. But you are leaving out important information in your description, which makes it meaningless from a special relativity standpoint, namely -- relative to what?

As they approach c their time slows down relative to the rest of the universe, earth included so that c stays c. Meanwhile on earth time is moving at at 'normal' rates relative to its own inertial reference frame. That is, as described from the Earth's reference frame, the ship has experienced less time than the earth. However, As described from the ship's inertial reference frame, it is the earth that has experienced less time than the ship.

There is no universal privileged frame of reference. You are treating the ship as moving close to light speed and the earth as stationary, but it is equally valid to treat the ship as stationary and the earth moving close to light speed. Each reference frame sees the other as having experienced less time. Seriously, read the link. It will do a far better job of explaining than I can.

Re:180,000 years

[Anonymous Coward]

They rolled the lower die and it's going to be a long wait.

Re:180,000 years

[Anonymous Coward]

I'll second that! We have a crew ready as well.
Now every tortured soul plagued with the dissatisfaction of living among the sensible and realistic of us , has a refuge.
The entire Baldwin family and many other Hollyweirds who've promised to leave to political utopias if Hillary wasn't appointed Goddess of the world, now have a place to go.
(Assuming Gliese is uninhabited, God forbid we start an intergalactic pissfight over sending Baldwins to anyone.)
Every downtrodden brotha bein' held down by tha man, Nation of Islam(ist?) bowtie Farrakhan flunky, Donkin' welfare breeder and any other NWA needn't have fear there won't be a black planet.( with the possiblility of owning their own Hollywood Democrat for labor and misuse)
We can send every alienated hippie, yippie, yuppy to a new CLEAN unpolluted Pellucidar where they can try to convince the brothas of the right way to live.
Every Democrat can run unopposed. Atheists can establish their own country. This may be a new frontier for $cientologists as well.( closer to Xenu)
We could send animal rights activists with an ark of nearly extinct critters. Every fringe special interest who feels left out, neglected, unsupported, misunderstood, downtrodden, offended or just a neuralgia can jump right in the hopper to be freeze-dried so that ride is just an unpleasant blink and heartbeat from over.
Yes, nirvana will be theirs as well as anything else on their iPods. We here on yucky ol' Earth will just have to muddle along with out them.
Bon Voyage! Don't take any wooden nickles.

Re:180,000 years

[Anonymous Coward]

Australia, I have it on good authority Camulus will be donating one half of his continent to the free Jaffa nation.

Re:180,000 years

[MillionthMonkey]

There is no universal privileged frame of reference.

There is no privileged inertial frame. Everyone on this site reliably talks about special relativity when this subject comes up, but special relativity isn't responsible for these particular time-dilation effects.

Considering just special relativity, a train's proper time is faster than the station's and the station's proper time is faster than the train's. The way out of that is to recognize that the entire concept of simultaneity is lost. If starter pistols are fired on the train at the first and last cars simultaneously (according to train passengers), in the reference frame of someone at the station, the two shots were separated by a finite time, varying linearly with train length. Although they agree on their relative velocity with respect to each other, they don't agree on the length of time the train spent in front of the station or even the length of the train itself. But both are inertial frames.

Until the train turns around. A reference frame which is not accelerating (i.e. an inertial frame) does have a privilege. The earth is in a free-fall inertial frame. A spaceship has to accelerate. If we're only going to consider the common time-dilation and length-contraction effects from special relativity, then relative aging makes no sense just from symmetry. If two spaceships left one point and returned to it after making mirror-image round trips in opposite directions, you wouldn't expect people in one to have specially and relativistically aged faster than people in the other.

But if you left the Earth, and then you returned to show off your youth or bring back rocks, there would have to be an acceleration involved when you turned around. That introduces the time-dilation effects from general relativity: clocks tick faster in free fall than they do on the ground, or any other non-inertial frame that experiences g-force. When the train actually turns around, all the stuff happens that amazes everybody on the return trip. When the train passes the station going the other way, it's pretty clear that everyone at the station has aged more.

In theory you could travel across the universe in your lifetime- but then your life would be ruined by extremely intense acceleration (a first). You'd have to bring a mixed-sex crew to create successive generations or else the mission fails.

Re:180,000 years

[Zenaku]

Thank you. This is exactly what I was trying to explain, though I was using incorrect terms and generally doing a piss poor job of it. You have clarified it beautifully.

Re:180,000 years

[RajivSLK]

I wish I had mod points... parent is relatively correct..

Re:180,000 years

[c6gunner]

I've heard this argument before, and I'm no physicist, but I'm pretty sure it's wrong. If all inertial reference frames were equally valid, there would be nothing to stop you from traveling faster than the speed of light. Also, looking out of your window and seeing the entire universe redshift might indicate that your speed is getting rather excessive. Either that, or you'd be standing there saying "wow, I'm standing completely still and the whole galaxy is moving at the speed of light!".

The argument appears relatively convincing at first glance, but creates all sorts of problems.

Re:180,000 years

[Rei]

You don't have to take the two extremes described in the article, though -- there is a middle ground between .92c / 22.4 Earth years / 6.1 traveller years -- and 0.00012c / 180,000 years.

Producing 530(/2) times the mass of a colony ship's worth of antimatter is pretty much a preposterous concept with current known tech. We just can't even come close. But there are a lot of techs that have been proposed that, while not as impressive as a pure matter/antimatter drive, are achievable with current tech. For example, antimatter-initiated microfusion looks like we could feasibly build a colony ship that could reach about 0.1c. That's 200 earth years / 199 traveller years. So it would need to be a generation ship, but then again, if you're planning to colonize, you better be able to handle reproduction and long-term habitation to begin with. Such a ship could conceivably be launched in ~50 years or so if there was sufficient dedication to the cause. That's far less than the time it'll take us to learn how to colonize a planet well enough for the mission (at 20 light years away, it has to be essentially 100% independent, all the way down to producing microprocessors and the like). This isn't Star Trek; even a planet in the "Goldilocks Zone" isn't going to be something you can just land on in your shirtsleeves and settle with nothing more than the phaser on your belt, like some space version of Jamestown. You need a large chunk of our planet's entire tech tree to maintain life support, mining, refining, and production infrastructure.

While tech does indeed change over time, I guarantee you, we're not going to learn how to produce those absurd amounts of antimatter for a matter-antimatter drive in a couple centuries.

Re:180,000 years

[Grishnakh]

That's not the way I remember it. The planet was colonized by a robotic "seed ship", with no humans aboard. The first generation was raised by the ship, and they bred the subsequent generations. The planet's population was quite small, but the planet had little habitable area anyway (it was almost all water). The newly-arrived ship was the last of the humans, and was packed with everyone left from Earth at the very end, in suspended animation. They stopped at the planet to see if they could live there, only to find there was no room, so they had to go on to another seeded colony planet. The new ship wasn't that much faster than the previous ships though; it still didn't have FTL, though it was powered by quantum fluctuations. Arthur C. Clarke never uses FTL in his stories, from what I can tell.

The main problem in the story is that this new ship needs to take some water from the planet to turn into ablative ice shielding for the rest of their voyage, as their shields have run out.

Re:180,000 years

[Grishnakh]

The entire Baldwin family and many other Hollyweirds who've promised to leave to political utopias if Hillary wasn't appointed Goddess of the world, now have a place to go.

Hey, Adam Baldwin is a cool guy!

Re:180,000 years

[dpilot]

It's been a few decades - I read it when it first came out, so I can go with your version. I'll have to check if I still have the book.

The one time Clarke had any sort of FTL was in 2001: ASO, and he repudiated that (to bad effect, IMHO) in 3001: TFO.

Re:180,000 years

[Rubinstien]

I still have the book (very yellowed with age), and Grishnakh is right in his correction. The later ship arrives much more quickly than the seed ship did, due to scientists discovering the necessary mathematics and techniques for harnessing zero-point energy, allowing a much more massive ship to be built that does not need to carry so much fuel. This ship is able to take along living human colonists, unlike the seed ships which contained only enough genetic material for the machinery on board to produce and educate the first generation. The particular seed ship that colonizes Thalassa is also one where the decision was made to exclude historical topics of religious and racial conflict from the education of the seeded colonists. The 'ark' containing the later colonists, obviously, provided no such opportunity for sanitizing history. One of the sources of conflict in the novel is this meeting of two societies -- an older, cynical, more worldly new arrival interacting with the newer, Utopian, and idealistic one. Other points of interest are that the technology brought along by the seed ship on this mostly-oceanic planet has already been noticed, has been stolen, and is accelerating the development of a native aquatic species. This topic is left as a cliffhanger at the end of the novel. Another is that the finale of the book is a mutual celebration held by the two groups in the novel, with videos of earth-based life played for the enjoyment of the Thalassians, and a concert to entertain all. Musician Mike Oldfield wrote to Arthur C. Clarke, asking permission to compose a suite based on the concept of this concert finale. The resulting album is also called, "Songs of a Distant Earth", and features a liner note by Arthur C. Clarke. The CD release was one of the very first "Enhanced CDs", containing a short virtual-reality sequence and a simple musical puzzle one must solve in order to unlock the video to the composition, "Let There be Light". The VR sequence and parts of the video, I have read, was rendered using early versions of Mike's software project, MusicVR ( http://www.mikeoldfield.org/info/discography/mvr.htm ). I also recognize some of the video sequences I had seen demonstrated from that in the old "Beyond the Mind's Eye" videos. Mike has since spent 25M pounds developing the software and games around it. The games can be downloaded from the sidebar of his fan site ( http://tubular.net/ ). I've never looked at them; I don't run Windows and I don't play games, but I think it is interesting just the same. A final point of interest is that Clarke supposes several technologies in this novel that he has since become known for, including the space elevator, and ablative ice shields to protect the ships from erosion by space debris. Indeed, replacing this ice shield is the reason the later ship stops at Thalassia.

Re:180,000 years

[DenDude]

Parent is correct. The difference is the acceleration used to get to near c. The folks on Earth are always subject to the acceleration of normal gravity.

The acceleration of the ship as it nears c is the "time-dilation" cause for the ship.

Re:180,000 years

[turgid]

If all inertial reference frames were equally valid, there would be nothing to stop you from traveling faster than the speed of light.

Wrong.

You cannot travel "faster than the speed of light" because no matter where or how you measure it, light always travels at speed c.

The wikipedia page on Special Relativity explains this clearly from first principles. Don't expect to understand this in half an hour. It will take a few hours of reading and doing worked examples. Since it is out of our sphere of everyday experience, it is not intuitive.

Re:180,000 years

[c6gunner]

lol. Well, thanks. I don't know what I would have done if you hadn't stepped in with your extensive wikipedia-based education. Now perhaps you'd care to comment on what was actually being discussed?

Re:180,000 years

[turgid]

A spacecraft is at rest with respect to Earth (for argument's sake). It might be in low earth orbit, ready to leave. To all intents and purposes their clocks tick at the same rate. Communication is to all intents and purposes instantaneous between them.

The rocket starts accelerating away from the Earth. The people on the Earth see the rocket moving away faster and faster. The people on the rocket see the Earth moving away faster and faster.

As the rocket approaches a substantial fraction of the speed of light, as observed from the Earth, clocks on the rocket appear to slow down. Light from the rocket appears red-shifted. The rocket's length contracts in the direction of travel. On Earth, the clocks there are still going at the same rate.

As observed from the rocket, clocks on Earth appear to have slowed down (by the same amount that the clocks on the rocket appear to have when viewed from the Earth). Light from the Earth appears red-shifted. The Earth has contracted in length along the direction of travel of the rocket.

The faster the rocket gets (as observed from Earth), the slower its clocks appear to run, the more red-shifted it looks and the shorter it gets. The people on the rocket appear to age more slowly.

Meanwhile, on the rocket, the people on Earth appear to be aging more slowly and clocks appear to run slower etc.

Another consequence of this is that wherever the rocket is going, the distance to its destination shrinks as seen from the rocket. For very high velocities, the more energy added (the more the rocket accelerates) this distance shrinks.

Put another way, if you are on this rocket you could effectively reduce the distance to anywhere arbitrarily if you could add enough energy with a sufficiently powerful engine and enough fuel.

The trouble is, it's an awful lot of energy.

By the way, the mass of the rocket also increases the faster it goes (and so does the Earth's). The Lorentz transform is the key to it all and comes from the principle of simultaneity.

Re:180,000 years

[c6gunner]

As observed from the rocket, clocks on Earth appear to have slowed down (by the same amount that the clocks on the rocket appear to have when viewed from the Earth).

This is the bit that's being contested. You can continue repeating it as many times as you want, but that doesn't really get us anywhere. Your assertion is - essentially - that time continues to pass at the same rate in both locations. Every other source says that an object traveling near the speed of light will experience time at a slower rate, so that - when it returns to it's starting point within the lifespan of those onboard - hundreds of years may have passed for those left behind. I'm open to having my mind changed, but you're going to have to do better than just flat assertions.

Light from the Earth appears red-shifted.

The universe appears red-shifted. When I'm driving down the road in my car, I could say that my house is actually driving away from me. But when the whole fucking planet is passing in the same direction, it seems a little egotistical to insist that my observation is the only one that matters, or even that they're both valid.

Actually, egotistical is the wrong word - fucking insane fits a lot better.

IIRC, your argument hinges on the idea that light observed to be coming from the earth will show the planet to be moving at a slower rate, which is true, just like it's true that my house appears to be moving away from me when I drive away. However, the twin paradox exists for a reason - we know that the person who actually IS traveling at velocities approaching C really will experience time at a slower rate, regardless of what he sees when he looks back at the earth. If it were true that both reference frames were equally valid, you'd see something different - both twins would see each other age more slowly while traveling away, and then see each other aging more quickly while traveling towards each other, with the end result that both would have aged exactly the same amount after being reunited. As long as we accept that this is not the case, we can safely say that time really does slow down as your velocity approaches the speed of light.

Re:180,000 years

[RancidPeanutOil]

I've never read any sci-fi about these earlier ships getting sent out, and then being overtaken and boarded by later ships, and then those ships being overtaken, etc., etc. Presumably they'd know what route was taken, and could add a few centuries/years/months/weeks/second to their trip to slow down and scoop them up. That'd also be a great way to encourage the whole human population to maintain reproductive compatibility on these millenia-long flights - just stock the earlier ships with women and some sperm banks, and tell the engineers back on earth that the girls got a head start, get to work. Even though it would take centuries to get anywhere, we'd keep catching up to earlier populations and mixing our gene pools with them.

Can I just skip the hard part and accept my Hugo now?

Re:180,000 years

[turgid]

Actually, egotistical is the wrong word - fucking insane fits a lot better.

The whole point of Relativity is that there's no "preferred reference frame" i.e. you can't just assume that you can measure things anywhere presumably against the universe as some kind of fixed backdrop (the Newtonian view) and expect to get the right answers. Speed, distance, mass, time and gravity all depend of the frame of reference in which they are measured. Two objects moving with respect to each other are, by definition, in different frames of reference.

It might be better if you read the Wikipedia articles on the Lorentz Transform and Special Relativity. The Lorentz Transform article explains simultaneity and measuring the speed of light leading to the Lorentz Transforms which lead straight to Special Relativity.

As I said before, Special Relativity is counter-intuitive because it is outside of our sphere of everyday experience. The only way to really understand it is by reading good articles on the subject that explain it from first principles and that use maths. It will take you a few hours of reading, thinking and trying the maths before you will really begin to appreciate it.

Arguing on a discussion forum isn't really sufficient.

Time travels at the same rate in the different locations for people at those locations. However, when they look at the other location from where they are, they will see time there traveling slower. Since there is no preferred reference frame, they both see the same effect. That's not insane, it's physical reality, the maths predict it and it is observable in Nature by experiment.

You're missing something very important about the Twin Paradox: that is how long it takes for information about one of the observers in one frame to reach the observer in the other.

It's 18 years since I went to university to study Astrophysics. In our first year, the Special Relativity text book we had was Special Relativity by A P French from the M I T Introductory Physics Series. It's clear and concise and you can buy it from the likes of amazon.com.

Re:180,000 years

[c6gunner]

The whole point of Relativity is that there's no "preferred reference

Yes, I get that. I've already acknowledged that. From a purely impartial perspective, it's completely valid. From a human perspective, it's retarded. As a child grows, we COULD say that the rest of the world is actually shrinking, but that would, likewise, be retarded. We could also say that both views are equally valid; this would also be retarded. It might prove useful in some circumstances, when playing around with abstract math, but when it comes to everyday discussion there's only one valid reference point.

It might be better if you read the Wikipedia articles on the Lorentz Transform and Special Relativity.

I've read them. I read them a long time ago. I re-read the article on special relativity when you first mentioned it, and I re-read the article on the Lorentz transform just now. I'm as familiar with the concepts as a person can be without fully grasping the mathematics involved. Neither article does anything to support your claim. Time dilation is still a real, observed phenomenon.

Time travels at the same rate in the different locations for people at those locations. However, when they look at the other location from where they are, they will see time there traveling slower.

Once again - already acknowledged. Again, you're just repeating the same assertion over and over.

You're missing something very important about the Twin Paradox: that is how long it takes for information about one of the observers in one frame to reach the observer in the other.

No, I'm not missing it - I explicitly stated that your entire argument hinges on the time needed for "information" (ie. light) to reach the traveling observer. I think YOU are missing something very important about the Twin Paradox: that the traveling twin WILL ACTUALLY BE YOUNGER than the stationary twin, upon his return to earth. No amount of wikibation can change that.

Re:180,000 years

[turgid]

...and the "traveling twin" will see the stationary one as younger...

So what would happen if the "traveling twin" turns round once he gets to his destination, and comes back at the same speed?

Re:180,000 years

[dpilot]

It wasn't about the ships getting overtaken, boarded, etc. In Clarke's book I had thought it was about a later, faster ship colonizing a planet, and then an earlier ship visiting that same planet on its way past. Apparently slightly defective memory.

In the Hitchhiker's and Gentle Voices cases, the whole purpose was to get rid of your "surplus popluation", perhaps a little less cynically than in "The Marching Morons."

Re:180,000 years

[c6gunner]

Just check wikipedia, ok? :)

Reality check

[elrous0]

Dave Goldberg, coauthor of A User's Guide to the Universe, took a more optimistic approach. In a blog post, he assumed an average travel speed of 92 percent of the speed of light

That is one HELL of an assumption. Considering that the fastest space vehicles ever created took 3 months to travel a mere 8 light *minutes* (somewhere around one-16000th the speed of light), the assumption that we will ever reach even a significant fraction of the speed of light with a vehicle created anytime in the conceivable future is a bit of an overstretch to say the *least*. At the speed of the Helios probes, that journey to this planet would take over 300,000 years, BTW. So even McConville's 180,000 year estimate is a bit optimistic.

And that's not even throwing in the navigation difficulties (that's going to require some epically precise calculations), the damage such a long trip would inflict to the craft with radiation and micrometeorites, the need for braking when you get there, etc.

Interstellar space is a big VAST empty that few people appreciate. When I was a kid, all the science fiction and popular misinformation made it sound like the next solar system started right at the edge of our own. It was only when I got older that I realized that our solar system is just a tiny dot in a huge sea of lonely empty. The scale of distances between solar systems is difficult for the human mind to even appreciate.

Re:Reality check

[Anonymous Coward]

It was supposed to be an optimistic estimate:

That is very bad news. Let’s put things in perspective and imagine sending the international space station (m= 370 metric tons) to Gliese 581g. The whole trip would require something like:

        * E = 1.8 x 10^25 Joules

Or approximately 5% of the sun’s energy output in a second. That sounds reasonable, until you realize that that tiny amount would take approximately:

        * 3 million years to collect on earth if the entire surface were covered with solar panels

That, as the physicists say, is non-trivial.

Better start building that Dyson sphere.

Re:Reality check

[dkleinsc]

Short version: "Space is big. Really big. You just won't believe how vastly, hugely, mindbogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space."

Re:Reality check

[MarcQuadra]

Right? The diameter of our solar system (Pluto's orbit) is about 80 AU. 80 AU is 0.0012 light years. This planet is 20 LY away. That means that it's about 1600 times as far as Pluto.

Remember, you need to bring along just as much fuel to slow down as you did to speed up. This is going to be a long, expensive, boring ride.

Re:Reality check

[elrous0]

The numbers are truly staggering. I remember my grade school teacher telling us that we would probably one day live to see spaceships traveling to other solar systems. I think now what a silly statement that was, but as a kid I was all "Yeah! Let's go!" All the Star Trek and Star Wars probably didn't help with the popular understanding either (not that they were meant to).

Re:Reality check

[Anonymous Coward]

Hey, if we figure out how to dramatically increase human life expectancy, she still might be right.

We'll certainly get that before we get interstellar travel, at any rate.

Re:Reality check

[frostfreek]

I think you missed a digit there; more like 16000 times.

Re:Reality check

[ari_j]

The Helios probes didn't exactly take 3 months to travel 8 light minutes. I'm not sure where you're getting the numbers, but most likely they mean that the probes took 3 months to get from perihelion to aphelion. The article you linked to on Wikipedia claims their speed record to be 0.000234c, which is over 1/5000th the speed of light, around 3 times the speed you quoted. That's only 100,000 years to go 20 light years. Still impractical.

The real question is the delta-v required to make the trip, including navigation along the way and corrections that must be made due to the impossibility of accurately calculating everything ahead of time. The minimal delta-v solution may indeed be around 180,000 years in duration, although other solutions may become practical with time to reduce that figure. Reducing it to only a few human generations in duration, though, will almost certainly require more than incremental improvements in technology.

For now, I think we're definitely better off pointing a radio telescope in that direction and trying to see what the early years of MTV were like for the Gliese 581g-icans.

Re:Reality check

[ari_j]

Oops. Perihelion/aphelion reversed, but of course the time between them is the same in either direction. :)

Re:Reality check

[Surt]

That's not true. There's a lot of interstellar hydrogen out there, you can use that as decelerant if you want. Acceleration and deceleration are often assumed symmetric, but that's not required, and given the distribution of resources not even the most effective way to do things.

Re:Reality check

[Anonymous Coward]

Why would you go to a chemist to get peanuts???

Re:Reality check

[interkin3tic]

Dave Goldberg, coauthor of A User's Guide to the Universe, took a more optimistic approach. In a blog post, he assumed an average travel speed of 92 percent of the speed of light

That is one HELL of an assumption.

If you read the actual post you'd see it was a setup:

Suppose you wanted to fly to 981g in smooth comfort. In that case, you’d want to accelerate at earth-normal gravity for the first half of your trip and decelerate at the same rate for the second half.

He goes on to say that doing that would get you there in 6 years, which isn't too bad. He points out it would only take about 5% of the sun's energy put out in a second.

That was all setup to the punchline where he calculates that to get that much energy, you'd have to cover the entire earth in solar panels and absorb energy for 3 million years.

So this was not a "Hey, we could totally do this thing!" blog post.

Re:Reality check

[natehoy]

Or determine how to slow down using energy at the destination.

Picture two HUGE but lightweight array of focusing mirrors capable of focusing sunlight onto a solar sail. Fire a set off using a small solar sail to the destination star, then it can use its own mirrors to slow itself down when it gets there. Once the mirrors reach a distant sun, they can be a permanent installation there for future trips, serving as decelerators for incoming ships and accelerators for outgoing ships.

So, you get a big push from one Sun when you leave, and your deceleration comes from another Sun when you arrive. Your onboard fuel needs would be relatively minimal. Basically enough for any course corrections while you're outside the effective range of both focusing arrays, and of course whatever energy you need to support whatever systems or people are on board for the journey.

Fantasy? Probably. But it's an intriguing possibility.

Re:Reality check

[quintesse]

All true, but the big question is: were the Helios probes made to get to their destination in the fastest possible way? Or more probable, get there fast enough while staying within the budget they were allotted? Are people really suggesting the Helios probes is the best we can do?

Not that I think we're going to suddenly come up with a hyper drive and I actually think it's not feasible to send anything yet. But maybe some day will be able to make something that gets there in a "reasonable" time and then receive the results a couple of generations down the road. A bit like those buried time capsules work, something that benefit future generations.

Re:Reality check

[MarcQuadra]

Oops, you're right.

Here lies PoopFace. Died of starvation out past the Oort cloud.

Re:Reality check

[spire3661]

Your math is a bit off, considering light and the spacecraft took VERY different paths.

Re:Reality check

[sconeu]

Turn in your geek card.

GP is a famous quote from "The Hitchhiker's Guide to the Galaxy"

Re:Reality check

[TheKidWho]

Who says Space Nutters aren't for life extension technology? I'm as much of a space nut as they come and I'm all for life extension tech :)

Re:Reality check

[CaptSlaq]

The lack of H2G2 knowledge is disturbing.

Re:Reality check

[Lord Ender]

Remember, you are criticizing an estimate which assumes we have vast amounts of antimatter at our disposal. Right now, it costs about $2.5b to produce one gram of antimatter. If we come up with a cheap way to make the stuff and stick a generator in orbit for a few decades, we may be able to put together a matter/antimatter engine that accelerates for far longer than anything we've yet manufactured.

This is new stuff; nobody is in any position to dismiss the possibility of being able to produce a rather kick-ass probe propulsion system at some point within the next few decades or centuries.

Re:Reality check

[invid]

Freeman Dyson, a very smart person, once calculated that an interstellar craft using thermonuclear bombs as propulsion (Project Orion) could reach 10% the speed of light. At that rate it would take a little over 200 years to reach Gliese 581. Time dilation would be minimal, so it would NOT be doable in a normal person's lifetime. But we could, with our current technology, build an unmanned craft that could reach Gliese 581 by the 23rd century and send back pictures.

Re:Reality check

[Remus Shepherd]

Dave Goldberg, coauthor of A User's Guide to the Universe, took a more optimistic approach. In a blog post, he assumed an average travel speed of 92 percent of the speed of light

That is one HELL of an assumption.

No, it is not.

The base of his calculation was that we want to fly at an acceleration of 1 Earth Gravity, for comfort. To do that we'd accelerate smoothly for 3 years, turn around, then decelerate smoothly for the last 3 years.

If you accelerate for 3 years at 1G, you end up traveling very, very close to the speed of light.

Now, there's a good argument that we have no technology capable of sustained acceleration for that length of time. But we certainly have the ability to accelerate for 1G for short periods of time. The limitation is fuel. But it's not outrageous to assume that one problem has been solved for a best-case estimate of this trip.

Re:Reality check

[denis-The-menace]

Yea but will all look like a cross between Darth Vader and RoboCop. No thanks!

Re:Reality check

[JustOK]

but Don't Panic.

Re:Reality check

[Jason Levine]

Emphasis on the "boring" part. Sci-Fi movies have conditioned us to think that space travel would be "start the journey, press the 'hyper-warp-jump' button, watch a light show out the windows for a minute or so and we're there." Instead, unless we discover some radical new way of traveling through space, it'll be "Start the journey, wait anywhere from a thousand to a hundred thousand years and we're* there." (*Where "we're there", really means "our descendents, born aboard the spaceship, are there even though we're long dead.")

And, even if you could make the trip to this planet in a "reasonable" amount of time, by the time you study the planet and return to Earth, the world will have changed dramatically. Even assuming we somehow cut the trip time to 1,000 years each way (and maybe froze you for the trip to keep you from dying en route), you'd return to a world 2,000+ years more advanced than you left. Imagine someone from Ancient Rome suddenly appearing in the present day and trying to get acclimated. The longer the trip, the worse the reintegration into society. Any manned trip would likely be one-way only at which point, we might as well send a robotic probe which won't need to eat, sleep or breathe.

Re:Reality check

[scorp1us]

Don't forget, that as you approach relativistic speeds collisions with the interstellar medium (~1x10^-5 particles per cubic meter) will produce violent reactions on the hull.

Re:Reality check

[jarbrewer]

Considering that the fastest space vehicles ever created took 3 months to travel a mere 8 light *minutes* (somewhere around one-16000th the speed of light), the assumption that we will ever reach even a significant fraction of the speed of light with a vehicle created anytime in the conceivable future is a bit of an overstretch to say the *least*.

No problem... A quick application of Moore's Law and we should be ready for launch in about 30 years.

Re:Reality check

[Anonymous Coward]

Plutos' orbit is 30-49 AU (http://en.wikipedia.org/wiki/Pluto), and you dropped a zero on the divide.

so

49 AU = 0.000774830082 light years (thanks Google)

20/0.00077... = ~25,812 times as far Pluto.

Re:Reality check

[openfrog]

The other aspect to the assumptions contained in "It's nice to think that we could get there is we mess up here" is that "we" would be a handful of us, the rest would have to live/die in the mess.

Re:Reality check

[Anonymous Coward]

I was trying to spark silly comments about dumdums who don't know know. Or annoy those that do. Why do you think I posted it as AC? :)

Re:Reality check

[BobMcD]

How fast do the comets and the like move through space?

How far do those go?

They're completely unpowered, so perhaps that would be a baseline?

Re:Reality check

[nedlohs]

Given the 180,000 year estimate you have 179,977 years to work on the tech for 0.92c travel and still get there faster than launching with current tech now...

Re:Reality check

[grumbel]

Considering that the fastest space vehicles ever created took 3 months to travel a mere 8 light *minutes* (somewhere around one-16000th the speed of light), the assumption that we will ever reach even a significant fraction of the speed of light with a vehicle created anytime in the conceivable future is a bit of an overstretch to say the *least*

That's hardly a fair comparison, as those crafts where never ever build for an interstellar journey. If you would go interstellar travel you almost certainly wouldn't start with your average chemical space rocket, but something nuclear or fusion based that could go a hell of a lot faster (assuming the anti-matter stuff is to much sci-fi to be practical). Project Longshot for example should be able to reach Alpha Centaury B in around 100 years and thats some 4.4 light years away and build with current day technology, so a trip to Gliese 581g should be around the 500 year mark. That is of course still a long time, but not something that should be impossible to handle, just really expensive and complicated.

Re:Reality check

[TheRaven64]

And, glancing over the equations in the blog, it looks like he gets the physics wrong. He seems to be assuming Newtonian physics, but at 92psl this is complete nonsense. Above about 10psl, special relativity starts to make the results diverge quite significantly from the Newtonian results. I'm too lazy to do the sums now (although the nice thing about special relativity is that it's about the most recent bit of physics where a high-school student can still do the maths without needing a computer), but I'd estimate that it would take around 20 years, maybe a bit more, in the reference frame of people back home.

Re:Reality check

[interkin3tic]

I'd estimate that it would take around 20 years, maybe a bit more, in the reference frame of people back home.

So did he. The 6 years was what the people on the journey would experience.

Re:Reality check

[elrous0]

Presumably, so would a probe send to this planet. Assuming we were actually trying to put it in orbit, and we're not just throwing it there as fast as we can (straight line, no braking, full speed). There would be braking, altering the trajectory, etc. I simplified the math, but even so, you're talking extremely impractical time frames and distances. As another poster pointed out, even at Helio's top speed, it still travels at less than 1/5000th the speed of light.

Re:Reality check

[Anomalyst]

The real concern is not the acceleration, do the math (E=MC**2) for a intersecting with 1 gram speck of interstellar detritus at 92% of the speed of light. Once again, Arthur C, Clarke probably had the most workable solution, an ice shield facing the direction of travel. This is going to HUGELY increase the mass of your vehicle, exacerbating the energy requirements needed to achieve any substantial fraction of C.

Re:Reality check

[elrous0]

Vision and fantasy are different things. Vision is saying "I know we can develop the technology to do this thing, and here is how we're going to do it!" then working hard to realize that vision. Fantasy is saying "someone" at "some point" is going to invent "something" to make it happen, with no idea how this something is going to work and no plans on how to even begin actually developing this "something."

Re:Reality check

[SpzToid]

The real question is the delta-v required to make the trip, including navigation along the way and corrections that must be made due to the impossibility of accurately calculating everything ahead of time. The minimal delta-v solution may indeed be around 180,000 years in duration

"Traveling through hyperspace ain't like dusting crops, boy! Without precise calculations we could fly right through a star or bounce off a supernova, and that'd end your trip real quick, wouldn't it?" Hans Solo

Re:Reality check

[Anonymous Coward]

Wouldn't you just go to Charles Schultz? Oh wait........

Re:Reality check

[Teancum]

To get your prophylactics, of course. And a couple other munchies to eat. Geez, have you never heard of a corner chemist selling stuff before?

(Hint: In America they are call drug stores.... as the AC here feels the wind rushing by)

Re:Reality check

[geekoid]

Depends on how you want to slow down.

You could go into a solar orbit and then use other gravity forces to slow you down.

Re:Reality check

[MetalAngel]

Where is the problem?
Let's allocate 10.000 years of research to develop a faster than light engine -
then it takes you another 20 years to get there.
Time to travel = 10.020 years.
Not possible?
May be.
But i think in 10.000 years of research - you can "bent" a lot of laws of physics.

Re:Reality check

[jschen]

I wouldn't rule out an unmanned space probe launched in the lifetimes of the younger /. audience and headed toward a nearby solar system.

Re:Reality check

[cgenman]

There are certain things in computing that take so long, you're better off waiting for technology to catch up a bit before even bothering to start out on the trip.

20 light years is so ridiculously far away, any ship you build now will be easily overtaken by a ship created before that first ship reaches 1% of its journey. Even building that ship is so far away as to be meaningless.

If you want to build a ship to go 20 light years from here, we need to first research enough technology and gain enough knowledge to build permanent stations in orbit. Then the moon. Then Mars. Build up a huge industrial base by increasing the number of humans we can support. Move from fossil fuels to more plentiful fuel supplies. And then, we're still light years away from hitting 20 light years off.

Re:Reality check

[ari_j]

Yeah, but Han Solo also used the parsec as a measure of time.

Re:Reality check

[MaskedSlacker]

Rule 34 my wayward son, carry on.

Re:Reality check

[smbell]

It's not just the distance between solar systems. The distance between the planets is consistently glossed over in various media. How many times have you seen some alien ship passing slowly enough by a planet that the planet stayed in view, but somehow this ship (or meteor...) will be at the earth inside a few hours. It's laughable. First the chance that it would actually be moving past another planet is rather remote, but if it was going to get to earth in any near timescale there would be hardly time for a quick flash as the object flew past the planet.

Re:Reality check

[Anonymous Coward]

Actually i'm from the UK and the chemists there don't sell munchies.
Well, they didn't sell them 10 years ago. At least, not my local one.

Re:Reality check

[Scragglykat]

But it's the interest that such a statement can peak in the mind of a youth that will eventually get us to the point that we can travel to other solar systems. If teachers told us, it'll never happen in a million years, would we even try?

Re:Reality check

[holmstar]

I guess you missed the word "diameter"...

Re:Reality check

[dtml-try MyNick]

If teachers told us, it'll never happen in a million years, would we even try?

Telling kids there are laws (of physics) that forbid them to do something? That mommy (nature) doesnt allow them to go there?

Are you kidding? We would have been there already by now.

Re:Reality check

[Anonymous Coward]

We should consider traveling virtually at the edge of light sending data backwards at the same speed through the spectral bands of light itself. I'm not sure of how this will be done, but the concept itself is enlightening.. (-Sitting in our chairs. We will bend light at will. We should be able at some point to get a pretty good look at new worlds then.)

Re:Reality check

[Anonymous Coward]

Build a launcher on the moon. Create a maglev rail "tube" that goes completely around the equator. We can do that with todays technology. Difficult and expensive yes, but completely do able and able to handle trains in 100's of tons. The moon its easy because of lower gravity, one side is going to be dark (hence superconductor with no additional cooling and coolant can be pumped to this cold side to cool the sunny side. While being able to launch extra solar sytem craft is handy it would be extremely profitable to move things off the moon making the moon the place to go to explore the solar system extremely cheaply (once built, almost free).

  Even if you only do one loop of the moons equator at a fairly sedate 5 G acceleration your going to be launching large (100 of tons) craft or probes at 10's or 100's of km per second at launch. A probe with 100G launch (at maybe a few tons) is going out a 100km/s. Then you add the delta v of the earths orbit around the sun and the moons orbit around the earth. You could launch several 100t trains a few second apart and assemble them together to form a huge ship.

  Then you turn its engines on. Even with something pretty conventional like VASPIR or solar sails which we can do today, we can get to 10% of light speed.

  I think its entirely conceivable that we will (start to) send probes to the nearest stars in the next 100 years. If we build a very small/light probe for a fly by.

  Lets not forget that some of the nearest stars are approaching us at over 20 km a second. In a few (10's of)thousand years the nearest star will be about maybe a mere light year away (Geliese 710)! Proxima will be closest (3.2Ly in 26000y). Things are only going to get easier!

Re:Reality check

[Anonymous Coward]

> That is one HELL of an assumption. Considering that the fastest space vehicles ever created took 3 months to travel a mere 8 light *minutes*

That is one HELL of a "considering...", using a speed record that no one has actually tried competing on yet. All ventures into space so far have only been concerned with getting there on the small budget available, not getting there as fast as possible. They've been coasting designs.

Note that I'm not saying 20 light years will be covered fast. I'm just saying it's dishonest to use a crappy non-record as the basis to say it's impossible.

Re:Reality check

[Anonymous Coward]

/me holds his towel high in the air with pride.

On a side note, my best friends girlfriend once knit him a towel with the words: "don't panic" inscribed in large, friendly letters. Oh, how I envyed him.

Re:Reality check

[Facegarden]

It was supposed to be an optimistic estimate:

That is very bad news. Let’s put things in perspective and imagine sending the international space station (m= 370 metric tons) to Gliese 581g. The whole trip would require something like:

        * E = 1.8 x 10^25 Joules

Or approximately 5% of the sun’s energy output in a second. That sounds reasonable, until you realize that that tiny amount would take approximately:

        * 3 million years to collect on earth if the entire surface were covered with solar panels

That, as the physicists say, is non-trivial.

Better start building that Dyson sphere.

I was looking around, and I found another interesting metric.

The largest nuclear bomb ever detonated was the Tsar Bomba, and had a 50 Megaton Yield. The wikipedia article claims that the average output of it was about 1.4% of the sun's output for 39 nanoseconds. So if you go off the estimate above, you'd need about 90,000,000 of those bombs to put out the energy required (5% of the sun's output for 1 second). That would weigh about 2.4 trillion kilograms, based on the 24 tonne weight of the original bomb. Still only a tiny fraction of the earth's mass though!

They said it could have put out 100 Megatons but was reduced for safety, so really we might only need 45,000,000 of those.

So we should get on that.

And then build an orion system.
-Taylor

Re:Reality check

[Anonymous Coward]

You DO NOT need as much fuel to slow down as you did to speed up, because you need to speed up all the fuel, but you only need to slow down half of it, except that since you don't need as much it's less than half. Not that it makes this feasible, but being right gives me something to talk about much of the way there. When you get tired of my other jokes and stories you'll beg me to tell you this one again...

Re:Reality check

[abednegoyulo]

Do not tell me it can't be done

-Franklin D. Roosevelt

Re:Reality check

[lennier]

Silly, you don't get the peanuts (for protein replacement) at the chemist, you get them at the pub, as well as the cheese sandwich (to save the microscopic space fleet) and the beer (to cushion the shock of the matter transference beam). The Babel Fish you have to get yourself from the Vogon hold, and your towel, well you just better know where that is at all times, is all.

Didn't they teach you anything at Galactic Sub-Etha Travel Journalism School?

Re:Reality check

[lennier]

I've always wondered why there's a War on Drugs in your country yet stores are allowed to brazenly sell them on every corner...

Re:Reality check

[Anonymous Coward]

But a robotic probe cannot colonise a planet unlike humans. What happens if there is life there? Is your robotic probe going to have the facilities to make first contact? To study them? What happens if there is life there but not as we imagine and the probe decides that there is no life?

Honestly, that far away, even with a robotic probe, we need better propulsion and communications technology...

Imagine 300 thousand years in the future. "Commander, we are receiving a signal from Gliese 581g, it seems to have structure. WE HAVE DISCOVERED LIFE. Oh wait, its just some probe saying that there is no life there... *O_o*"

Re:Reality check

[Kjella]

Personally, I'd be willing to wager a pretty good bet that the first probe we send won't be coming home. In fact, it probably won't brake at all it'll just speed past like a bullet, record as much data as possible and transmit it to earth. And that's only after we've exhausted all other options to point huge telescopes and radio arrays and whatever else at it. Personally I figure even if we find Earth II we'll spend at least 100 years trying to observe it better from here and 1000 years waiting for that probe. If we're to see it there better be some breakthroughs in immortality first.

Re:Reality check

[Grishnakh]

And that's not even throwing in the navigation difficulties (that's going to require some epically precise calculations), the damage such a long trip would inflict to the craft with radiation and micrometeorites, the need for braking when you get there, etc.

I'm not so sure radiation and micrometeorites are a big problem in interstellar travel. Intrastellar travel, sure, but once you're well away from any star system, there shouldn't be much out there. The radiation comes from the stars, and asteroids are almost always stuck in star systems by gravity.

Re:Reality check

[Lanteran]

something only 2 to 3 people per thread seem to know is that with current technology (project orion using 100Mt tsar bombas for propulsion) we can reach .10C! The trip then takes from 40-50 years. With a sleeper ship, or better, an antimatter orion capable of going .80-90C (time dilation makes the trip last mere months for those on board), you could easily live a long, full, and productive life, then retire on alpha centauri or come back to earth. Oh wait a second, forgot we were talking about Gliese 581. Make that 200 years for current tech, 30 years for antimatter orion, still something that could be considered.

Re:Reality check

[squizzar]

Makes me think of the Roamers from Kevin J Anderson's Saga of Seven Suns - a colony group that essentially become space gypsies; they live in space stations and harvest resources from gas giants and meteor fields.

I suppose that if we developed large enough habitats in space then we could reach a point where cutting a large, mostly self sufficient (except resources etc.) space station adrift and pointing it in the general direction of some other solar system is plausible. Many generations would pass but eventually they might get there, I wonder whether they'd want to leave space for a planet when they did?

Re:Reality check

[Mr.Intel]

Also don't forget about cosmic rays. Shielding colonists or an exploratory crew is also non-trivial. High energy protons do bad things to DNA and secondary radiation from hull penetration is bad stuff.

Re:Reality check

[Mr.Intel]

I'm not so sure radiation...[is] a big problem in interstellar travel. ...once you're well away from any star system, there shouldn't be much out there. The radiation comes from the stars...

Do some research first before speaking out of your nether regions.

Re:Reality check

[default luser]

I wouldn't rule out an unmanned space probe launched in the lifetimes of the younger /. audience and headed toward a nearby solar system.

Okay, but now you have three new problems to deal with:

1. We've yet to build electronics that can run for 100 years non-stop, let-alone 100,000 years in the depths of space. The Voyager probes have survived, but that's barely breaking the 30-year mark. If the electronics can't survive, then there's no point in sending it.

2. Our models of this new solar system are crap compared to models of Sol, because our methods to observe planets are very clumsy due to the vast distances. So, the probe will have to anticipate some significant course correction burns during the trip, instead of just selecting one optimal terminal trajectory. This means the probe will have to be massive to carry enough fuel - on a totally different scale from any spacecraft we've ever built. That, or it will have to include exotic (read:not invented yet) propulsion systems.

3. Next, you have the transmission problem. So, you sent your probe, and now it has to send back pretty pictures and tons of data. But to do that, you need POWER. The Voyager probes have already nearly reached the limits of their on-board transmitter, and they've barely left the solar system (a couple thousandths of a light year). If you want to send a signal over 20 light years, you're going to need some impressive power.

Yeah, you could use something more efficient (like a tight laser), but the tighter you make the beam, the more likely we are to miss it. Remember that this space probe will be GUESSING where the earth will be after ~20 years, transmitting from a massive distance away, so wider is better. Really, the only thing that powerful is a star...the same thing we're using to identify a planet 20 light years away.

Re:Reality check

[Gilmoure]

I thought fantasy was being involved with hot chicks in chain mail bikini's.

Or with hot chicks.

Or chicks.

Re:Reality check

[Anonymous Coward]

The Earth is 1 AU form the Sun, so if Plutos orbit takes it between 30 and 49 AU, we can be anywhere between 29 and 50 AUs from Pluto depending on the orbits of the Earth and Pluto. So maybe he ignored the word diameter because the diameter of Plutos orbit isn't the same as the distance from Earth to Pluto.

Maybe you should have paid more attention in your Maths and Science classes at school, then you'd know this.

Re:Reality check

[Anonymous Coward]

Short version: "Space is big. Really big. You just won't believe how vastly, hugely, mindbogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space."

There is only one point that covers all in this article, as much as we want to make things go faster, Im sorry to say that in the laws of physics we can only travel 99.9% of the speed of light and we can't surpass it, if you would refer to Stephen hawkings time travel theory some of the facts and examples that were relayed there "note: facts not theories, included to form the theory"

        There was a machine mentioned in the book that accelerates microscopic particles making them travel 99.9% of the speed of light after which they would breakdown, basically speaking in the laws of Physics theres a force hindering us to gain 100% mimic of the speed of light and thats the problem.
Although sometimes laws physics is defied we can never say. We are only talking of particles here that we speed up and not a spaceship, imagine how far we are behind in doing such a feat

Re:Reality check

[Anonymous Coward]

What if we built a craft with an Integral Fast Reactor and VASIMR engine, go 110% on the reactor and turn the speed dial to 11. Probably could get under 100K years.

In a word: NO.

[snarfies]

Well hell, if we develop wormhole technology, we can open a gateway, visit Gliese 581g, and be back home in time to watch the next episode of Fringe. Can I be quoted in the Discoblog too?

Nuclear pulse propulsion

[CompressedAir]

Project Orion could get us there.

Re:Nuclear pulse propulsion

[Xtense]

The theoretical speed for a momentum-limited, 100m orion craft would be 3,3% of the speed of light, so... no. No it wouldn't.

Re:Nuclear pulse propulsion

[MozeeToby]

I'd really love to see some college actually do a study on if it would be possible or not. It's hard to say without real research just how much and what kind of resources an ark ship would need over those kinds of timescales. What's the theoretical rate of atmosphere loss? How efficiently can waste be recycled and put back into the ecosystem?

Using a sperm bank to dramatically increase genetic diversity would significantly reduce the minimum size of the crew, an all woman crew would further reduce the size but would probably cause all new problems. A vegan diet reduces the need to support non-human animal mass, but adds a requirement to be able to synthesize some vitamins and proteins. Enough redundant manufacturing to produce spare parts for everything, including the manufacturing facilities. IMO, it looks hard but not impossible with today's technologies.

Re:Nuclear pulse propulsion

[CompressedAir]

Hopefully you can recognize the assumptions in your statement.

Re:Nuclear pulse propulsion

[maxume]

Until one actually does it, you are also making assumptions.

Re:Nuclear pulse propulsion

[Mr. Slippery]

A vegan diet reduces the need to support non-human animal mass, but adds a requirement to be able to synthesize some vitamins and proteins.

No, it doesn't. Protein needs are easily met on a vegan diet; the only vitamin that can really be troublesome is B12, which is made by bacteria and so doesn't need to be synthesized.

Re:Nuclear pulse propulsion

[TheKidWho]

100m? I think we can do better than that.

Re:Nuclear pulse propulsion

[rubycodez]

what's the problem? generational starship taking a few hundred years to get somewhere isn't beyond the realm of engineering.

Re:Nuclear pulse propulsion

[HeckRuler]

Uh, before we get into the nitty gritty of how we knock up women in a generational space-ark, maybe we should try to use nukes as a propellant first. You know, see if we can smack a probe into the next solar system and still have it function in some method. The Orion Project is a neat idea, but so far it's ONLY an idea. I'm just saying, before we build an ark, how about we see if we can get something to float?

Re:Nuclear pulse propulsion

[David Jao]

The theoretical speed for a momentum-limited, 100m orion craft would be 3,3% of the speed of light, so... no. No it wouldn't.

You missed the point completely. 3.3% of the speed of light isn't enough to get there within our lifetimes, but it's a lot faster than the estimate of "180,000 years based on current space flight technology" quoted in the summary.

And make no mistake, Project Orion is completely feasible with present-day technology. The only reason why people avoid mentioning it is because it contains the dirty word "nuclear".

Re:Nuclear pulse propulsion

[Anonymous Coward]

Animals don't make nutrition. Vitamin D is created by sun exposure in humans and other animals, and is not a significant part of milk until it is added artificially.

On the subject of an all female crew, don't forget that we can send frozen eggs along with sperm. As long as we have a few females, if they are real troopers, they could each have a baby a year. Each baby would have sperm AND an egg from a different mother and father. The next generation could reproduce with each other safely even if they were born of the same mother, and they could also supplement themselves with more frozen sperm and egg babies for many many more generations.

This is all assuming we don't have an artificial womb. Imagine sending just the sperm, eggs, robots to set up the environment, and then finally when they get the OK from us, they could raise an entire generation of humans. The robots would feed them, but videos from us that were sent along and keep getting beamed could educate them and teach them to communicate with each other. Of course we would get data beamed back so we could respond, years later.

Re:Nuclear pulse propulsion

[GrumblyStuff]

Notice he didn't say how long it would take.

Re:Nuclear pulse propulsion

[Anonymous Coward]

If it's an all female crew it's probably better if they are gay so that all their /needs/ are met. Also, obviously, they need to be young and healthy.

Where can I sign up to donate to the Vegan Lesbian Space Cadets?

It's for the sake of humanity!

Re:Nuclear pulse propulsion

[geekoid]

Or jsut take chickens. Or a protein slurry would probable be the most economical way to do it.

Re:Nuclear pulse propulsion

[Anonymous Coward]

Umm. You are forgetting your fat needs. And all plant sources of fat are heavy in omega 6, which is inflamatory... So, if you plan on having all of your crew die of poor health due to bad diet, by all means, forget the animal foodstuffs.

Re:Nuclear pulse propulsion

[Anonymous Coward]

Plant sources of fats are very variable. What fats do you suggest these astronauts consume, and from what animal source? The only fat that is even remotely unique to animals is omega 9, which is not essential at all since we make it ourselves with ease.

Omega 6 is an essential fat, so calling it inflammatory is pointless. Consume what the body needs, and no more. We also need omega 3 fats. Flax is an excellent source of this, but it has no DHA. For DHA, we would feed astronauts algae.

Or are you suggesting that we feed astronauts fish for omega 3? Please educate yourself on nutrition first. Fish get omega 3 by eating algae. They don't create it themselves.

Re:Nuclear pulse propulsion

[c 0xFF]

...an all woman crew would further reduce the size but would probably cause all new problems.

This gets my nomination for the Understatement of the Year Award.

Re:Nuclear pulse propulsion

[jonwil]

The answer to the "the diet would be missing xxx important nutrient" problem is to do what people on earth do when they need more of it. Take a vitamin pill of some kind.

So you eat whatever normal food is required to get most of your nutrients then you take a vitamin pill to get the stuff the food cant provide.

Re:Nuclear pulse propulsion

[Anonymous Coward]

An all-woman crew could be maintained through some sort of test-tube baby setup.

Re:Nuclear pulse propulsion

[Anonymous Coward]

A vegan diet reduces the need to support non-human animal mass, but adds a requirement to be able to synthesize some vitamins and proteins.

No, it doesn't. Protein needs are easily met on a vegan diet; the only vitamin that can really be troublesome is B12, which is made by bacteria and so doesn't need to be synthesized.

The cow says moo - hippy.

Re:Nuclear pulse propulsion

[Anonymous Coward]

But you would have to find intelligent vegans and I see that as a problem.

Re:Nuclear pulse propulsion

[QuantumPion]

Calculations here: http://math.ucr.edu/home/baez/physics/Relativity/SR/rocket.html

Basically, to just send a probe that flies by without stopping, it is remotely plausible (you would need 60 kg of antimatter for every kg of payload).

Re:Nuclear pulse propulsion

[Gilmoure]

That's just because some folks have a hard time pronouncing it.

Re:Nuclear pulse propulsion

[Gilmoure]

It's the sociological implications of a generation of humans raised by computer that I find interesting. Growing up, they might find Ren & Stimpy more relevant than Sesame Street.

Takes my breath away!

[Drakkenmensch]

Let's make sure first that it has, you know, oxygen, and not one of those 95% carbon dyoxide air content some younger planet lacking vegetation may have. Or one of those fancypants sulfuric acid atmospheres that melts your lungs.

Re:Takes my breath away!

[Fulcrum of Evil]

Kids today! When I was a lad, we would've killed for a Sulfuric Acid atmosphere. We had to make our own air!

Re:Takes my breath away!

[mcgrew]

The thought occurred to me that perhaps we shouldn't be looking ONLY at earth-sized planets in the goldilocks zone. It seems that a Jupiter or Neptune sized planet in the goldilocks zone could have moons capable of supporting life.

Could we get there? Not by any technology currenly even envisioned. Hell, the Voyager probes are barely past the heliosphere, and they've been travelling for almost 40 years now.

Re:Takes my breath away!

[dkleinsc]

You were lucky. We had to cobble a planet together out of dust in an protoplanetary disk!

Re:Takes my breath away!

[wjousts]

Well, you can always just turn around and come back if it turns out that the atmosphere isn't any good when you arrive.

Re:Takes my breath away!

[WormholeFiend]

Pfft. We had to detonate our own bigbangs.

Re:Takes my breath away!

[nschubach]

Talk about a downer...

"Hey guys! We're here. Unfortunately, we can't land because the planet is non-habitable so we are headed back."

(For some reason I just imagined a ship that's been sailing for years full of sad pirates being turned away from an isle full of beautiful mermaids because they breath water.)

Re:Takes my breath away!

[Anonymous Coward]

Talk about LUCK. I had none of that; I had to arrange the protons and electrons individually, one by one, atom by atom, uphill, in a blizzard.

Re:Takes my breath away!

[wjousts]

Not as much of a disappointment as getting back to Earth 360,000 years after you left and finding out that in the meantime they've developed technology to get from one star system to another in the blink of an eye and have since colonized most of the know galaxy. It just nobody remembered the ship they sent out several hundred thousand years ago, so nobody thought to catch up with you and let you know. Bastards!

Re:Takes my breath away!

[Anonymous Coward]

Is that why old people are so gassy?

Re:Takes my breath away!

[jgagnon]

God? Is that you?

Re:Takes my breath away!

[catbertscousin]

You had big bangs? WE had to randomly smash atoms together and if we were lucky we might get a fizzle!

Re:Takes my breath away!

[Tablizer]

You were lucky [kids]. We had to cobble a planet together out of dust in an protoplanetary disk!

Oh yeah? Well in my day I had to make the dust from nothing. -God

Re:Takes my breath away!

[suomynonAyletamitlU]

Dust! I had to scrap together a ball out of ice, while spacefaring barefoot--going against the gravity gradient, both ways!

Re:Takes my breath away!

[TheRaven64]

It just nobody remembered the ship they sent out several hundred thousand years ago, so nobody thought to catch up with you and let you know.

Or that the technology only allows you to travel between two points of equal gravitational potential, so you can't use it to reach a ship in interstellar space, only to travel between the vicinity of two stars...

Re:Takes my breath away!

[wjousts]

Yeah, that was the same BS excuse they tried to give me. They're still Bastards.

Re:Takes my breath away!

[Anonymous Coward]

You mean YOU can't live there, or life can't be there?

If the former, sure, but if the latter: http://en.wikipedia.org/wiki/Archaea#Habitats

Damn you, Fermi!

[RobertB-DC]

Damn you, Enrico Fermi, and your infernal paradox. Damn damn damn!

Re:Damn you, Fermi!

[mcgrew]

We could be picking up extraterrestrial signals right now and not even know it. For example, instaed of using binary computers they could be encoded in trinary, 0=off, 1=positive, 2=negative. It's a certainty that of there's extraterrestrial life it will be nothing whatever like humans.

If a sentient civilization never thought of frequency modulation, then they would not see any TV shows. Or perhaps there are other ways of modulating a radio signal besides amplitude and frequency that we've never thought of that is just so obvious to them that AM and FM never occured to them.

They may not even use radio waves to communicate. They may have discovered something we haven't, while not discovering EMF themselves. Hell, perhaps they're blind to emf and have some other sense that Earth life lacks that gave rise to an "obvious" technology that we're completely blind to.

As to finding an alien spacecraft in the infinite emptiness of space, the odds are so close to zero that if you tried to divide by it your computer would crash with a "divide by zero" error.

We still haven't found extraforgostnic life

Re:Damn you, Fermi!

[IndustrialComplex]

Wait I forget, is it worse to prove a paradox wrong, or to prove it right? ;)

Re:Damn you, Fermi!

[MozeeToby]

There are ways to analyze potential information even if you don't know what you're looking for. Basically, you want to know how 'random' the signal is that you're looking at, regardless of what kind of data or how the data is encoded it is going to be non-random unless it is heavily encrypted.

Re:Damn you, Fermi!

[green1]

This still assumes that you know how to at least receive the signal.

Imagine a culture that never invented radio, they transmit everything wired or visually. that wouldn't preclude a highly advanced civilization, it just wouldn't necessarily be detectable from our vantage point.

And that's only one of an infinite number of ways we could be wrong.

As long as we only look for life that conforms to what we know on earth, we'll never know what other forms it can take.

Re:Damn you, Fermi!

[MozeeToby]

Today's SETI pretty much assumes that ET is trying to get a hold of us. Omnidirectional signals get washed out by the background noise at any appreciable distance, we simply don't have the antennae to detect anything other than a directional blast right at us. And if you're going to assume someone is trying to communicate you're going to look in the parts of the spectrum that will travel the farthest without being washed out. You're going to assume that there is some relatively easy to detect carrier information. You're going to assume that they are going out of their way to be understood.

You can of course make an argument that any alien life will be so different from us that those assumptions don't hold, or that they are so different that we can't even detect their active attempts at communication. But the best method that we've come up with to talk over interplanetary or larger distances is radio, unless we're missing some branch of physics it's likely that any aliens would come to a similar conclusion.

Re:Damn you, Fermi!

[green1]

My point is that while receiving something would be proof of something, the lack of receiving something (or the lack of noticing such a transmission) does not prove anything.

Life may be as similar to us as the people next door, or so different that face to face we would insist it is not life at all. Any attempt at detecting it is valiant and noble, but assuming it can't be different is just arrogant.

I'd like a second opinion...

[tverbeek]

How long would it take at warp 6, Ensign Chekov?

Re:I'd like a second opinion...

[Per Wigren]

18 days, 13 hours, 26 minutes and 24 seconds, captin.

Re:I'd like a second opinion...

[JackCroww]

Did you guess, or did you look it up? If you guessed, damn, not bad.

Re:I'd like a second opinion...

[frostfreek]

That reminds me, why does it take about an hour to travel to Vulcan, and then something like 48 hours to travel back to Earth, when it's about to be destroyed by a drop of red matter? Solar wind?

Re:I'd like a second opinion...

[Anonymous Coward]

Ooh! Ooh! Say, "nuclear wessels!"

Re:I'd like a second opinion...

[gstoddart]

How long would it take at warp 6, Ensign Chekov?

"Ensign authorization code Nine-Five-Wictor-Wictor-Two."
"Authorization not recognized."

Re:I'd like a second opinion...

[Anonymous Coward]

Surely you know that they were suffering a weasel infestation in their warp manifold?

Re:I'd like a second opinion...

[sconeu]

No, the Enterprise has a "Crisis on Earth" detector that alters the warp field to slow down the ship for dramatic effect.

Re:I'd like a second opinion...

[Per Wigren]

Nuclear wessels.

Re:I'd like a second opinion...

[Per Wigren]

By the way, Sir, that's a Russian inwension.

Re:I'd like a second opinion...

[natehoy]

Fuscia Matter, silly boy!

In the Abrams' Trekiverse, all plot holes will be explained by different-colored bits of matter. The reason for this is simple. Burnt Umber Matter made it that way.

Re:I'd like a second opinion...

[jgagnon]

Nuclear weasels! Wait, that isn't right...

Re:I'd like a second opinion...

[M8e]

Nucular weasels!

Re:I'd like a second opinion...

[BlueStrat]

While you are at it, ask Obama if we can do it.

Obama: Yes we can! but unfortunately we won't cause the NASA budget is gone!

What we need is a perpetual motion machine.

Perpetual motion?? Great Scot man, *why*!?!?

I'd prefer he *stopped*, so the budget isn't always gone!

Strat

Re:I'd like a second opinion...

[Gulthek]

They weren't going to Earth until Kirk took command.

Re:I'd like a second opinion...

[TheRaven64]

Geek Fail. That page uses the scale from the Next Generation, while Ensign Chekov would obviously have answered using the scale from the original series. By the original series scale, it would take just under 34 days.

Re:I'd like a second opinion...

[Per Wigren]

I realised that after posting but hoped that nobody would notice. :(

I know how to get there!

[Overzeetop]

Just convince some corporation that it has unobtainium.

Re:I know how to get there!

[bareman]

Tell the Tea Party there are tax free land grants there.

Re:I know how to get there!

[elrous0]

Where the lakes are made of petroleum and the mountains are made of gold!

Re:I know how to get there!

[jbeach]

Oh man, please let all of them get into some Space Ark and head out, and good luck to them. I wouldn't even point out to them the irony that the ship would be made with public funding.

Re:I know how to get there!

[Anonymous Coward]

Tell the liberals that it's Pelosi's home planet.

Re:I know how to get there!

[Tablizer]

or convince a big religion that there's Holy Land there.

Re:I know how to get there!

[Anonymous Coward]

Just convince some corporation that it has unobtainium.

Yeah...just what we need...another human endeavor to destroy another world faster than they've been able to destroy this one. If corporations were great stewards in taking care of the earth...I would feel different.

Re:I know how to get there!

[Sunshinerat]

With them we should send all the telephone sanitizers, hairdressers and advertising account executives so that they can prep the environment before the other ships arrive.

Re:I know how to get there!

[antdude]

Or oil? :)

Re:I know how to get there!

[tmosley]

Richard Branson might have something to say about that.

Re:I know how to get there!

[lennier]

But we can't obtain any of that!

Now exceedinglyscarceyeteasilyextratedium, find that and we'll be in business!

Re:I know how to get there!

[CowFu]

Can we please please please PLEASE keep the partisan political garbage off of slashdot, this is my last sanctuary against this crap.

Re:I know how to get there!

[TheDarkMaster]

Very funny, but true too... Give a goal good enough (for example, asteroids have lots of rare and precious metals) and soon we will have the necessary technologies, funded by the corporations interested

Jerome Kerviel will be free and clear by then!

[sgt101]

http://www.telegraph.co.uk/news/worldnews/europe/france/8044599/Jerome-Kerviel-will-need-177000-years-to-repay-5-billion.html

Well - he'll have had 3000 years to enjoy his income at that point!

the question is why ?

[carlosap]

Why do we want to go there ? Poor aliens if we can go there. May be there are far far away on purpose.

Re:the question is why ?

[Fict]

may be there are far far away, with there babbys

Re:the question is why ?

[shutdown -p now]

Expanding one's living space whenever and wherever possible is a common trait of pretty much all living species. Humanity is no exception.

star gates are much faster!

[Joe The Dragon]

star gates are much faster!

more like a few seconds.

Re:star gates are much faster!

[CoolCash]

But you still have to get one on the other planet. Unless you create a ship that seeds the universe with stargates.

Re:star gates are much faster!

[Anonymous Coward]

Duh this what The Ancients are for!

Re:star gates are much faster!

[arbitraryaardvark]

in a universe without walls or fences, who needs windows or gates? - Muso Soseki, 1340.

A further shore....

[Braintrust]

Technological limitations aside, this is the first time in several hundred years that we have had a further shore to sail to... a place where no man has gone before, as the saying goes.

That has to count for something.

For me this is the most profound discovery in the history of us. Without hyperbole. The only thing I can see superseding it is, of course, the confirmation of life itself out there.

I think we need a further shore... and I'm glad I lived to see a new one.

Re:A further shore....

[dasherjan]

We already have plenty of shores to explore in the solar system. They're just not as sexy as another earth type place. ;-)

Re:A further shore....

[Mastadex]

People say we need another space race to kick off another golden age of technological achievement. Well, this planet seems like a fairly lucrative goal considering it's the equivalent of a 'new route to India'. We just need a Christopher Columbus to spear head this endeavor.

Re:A further shore....

[Anonymous Coward]

There are lots of inhospitable, barren rocks in the sea.

No one who sails refers to them as "shore."

Re:A further shore....

[PinkyGigglebrain]

Excluding:
Mars, Callisto, Ganymede, Europa, Titan, Pluto, Mercury, Iapetus, Miranda, Charon, Eris and a bunch of other "further shores" I have forgotten the names of that are just a tad closer to home.

But I agree on your other point, Gliese 581g is, possibly, a truly profound discovery. If improvements in remote sensing and telescopes reveal that this new world has an Oxygen rich atmosphere or other solid indications of life (radio?) then it will likely be the most profound and culturally altering discovery ever made since the development of mathematics and writing.

Re:A further shore....

[Kozar_The_Malignant]

We already have plenty of shores to explore in the solar system. They're just not as sexy as another earth type place. ;-)

You only say that because you haven't seen the beach babes along Titan's shores. Granted the "water" is a bit chilly, but you can't have everything.

Re:A further shore....

[Anonymous Coward]

"For me this is the most profound discovery in the history of us."

More than fire? Cooking? Agriculture? Uhm, science? Medicine? Washing your hands before surgery? Indoor plumbing? Discovering that fossil fuels can power an entire technological civilization?

An uninhabitable rock light-years away doesn't matter for 99.999999% of the human race. Getting food in their bellies three times a day does.

Re:A further shore....

[Anonymous Coward]

Grammar note: should be FARther.

Re:A further shore....

[im_thatoneguy]

What about Mars?

Re:A further shore....

[Anonymous Coward]

Christ, this site is so full of shitheads. Where do you people come from, and why do you not stay there?

Re:A further shore....

[Anonymous Coward]

You mean some nutjob to come along and say "according to my calculations, it's not 20 light years away, but rather 6 billion miles. Fund me." who then serendipitously comes across a different planet and declares it to be Gliese 581g?

Re:A further shore....

[arcsimm]

.

(padding here because Slashdot doesn't recognize the laconic wit of Trafalmadorian)

Re:A further shore....

[whathappenedtomonday]

That might be the reason why - according to the blog post you didn't read - the first of the "important steps to achieve this goal" is:

1. A decision must be made on what constitutes an Analytical Engine

Re:A further shore....

[Confusador]

I really do hate to rain on your parade, but I feel a sort of scientific obligation to point out that the only thing we know about this planet is size and distance from star. It really could be a barren rock or a greenhouse hell like Venus, for all we know. Hopefully soon we'll be able to know more, and I'm confident that even if this isn't it we'll find one soon.

But we're not there yet.

Re:A further shore....

[SleazyRidr]

I think we need a further shore...

As long as it's not the Jersey Shore, I'm happy too.

Seriously though, that planet is far enough away that it may as well not exist for us yet. The Moon, Mars and Asteroids are all good shores for us right now.

Re:A further shore....

[Anonymous Coward]

Uh, Mars?

Re:A further shore....

[SETIGuy]

For me this is the most profound discovery in the history of us. Without hyperbole.

Unfortunately the announcement of this discovery was accompanied by way to much hyperbole. For all we know this planet could have runaway greenhouse, be fully covered with a 300 mile deep ocean, or have no liquid water whatsoever. We'll need some really huge space telescopes to confirm its properties before we could justify making this journey with an unmanned probe. By big, I mean a few years of the US military budget to pay for them (My very rough estimate is $1.5T to get an image of the planet, but since the technologies don't really exist it could be less or a lot more). Even that would be cheap compared to sending the probe.

In other words, it ain't gonna happen in our lifetimes unless unlimited free energy is discovered soon.

Re:A further shore....

[Anonymous Coward]

I think we need a "steel beach" (John Varley), first. That'll teach us (=next generations of schoolkids) something fundamental about ecology.

Radio

[mukund]

How about sending some targeted "Hello world" transmissions towards that object first? If they have any intelligent life and a SETI program in place, they may hear us and answer back.

Re:Radio

[nschubach]

Wouldn't you have to wait 40 years for the reply though? (Radio in space travels at the speed of light, right?)

Re:Radio

[Shadyman]

I read somewhere that they might be intentionally ignoring us until we develop warp capability.

Re:Radio

[elrous0]

In 40 years we'll get "This is my first program!" in response.

Re:Radio

[Anonymous Coward]

No, shhhh. We want it to be a surprise...ATTACK, THAT IS!!! BUWHAHAHAHAHAHA!

Re:Radio

[Capt.DrumkenBum]

I think that was Star Trek: First Contact.
http://www.imdb.com/title/tt0117731/

Re:Radio

[Scud]

...If they have any intelligent life and a SETI program in place, they may hear us and answer back.

That's if they don't send us straight to voicemail.

Re:Radio

[blueg3]

Yes, light travels at the speed of light.

Re:Radio

[Mitchell314]

Not that big of a deal. I've had longer pings from my ISP.

Re:Radio

[CFBMoo1]

*** Translating Transmission ***

From: Earth
To: Gliese 581g
Subject: Menu

Greetings from Earth! We're about 4-7 feet tall and have a large population on our planet. Do you have water like we do? We go well with greens! Please feel free to drop us a line!

Regards,
Earth

Re:Radio

[MoonBuggy]

Yeah, but I'd still say it's a good plan. Considering the outlay (minimal - point a big ass laser or radio dish in the right direction, pump out a sequence of prime numbers or some such for a while), the potential reward (a very small, but nonetheless plausible, chance of discovering extraterrestrial life), and the other realistic options (do nothing), I'd say waiting for signals with a 40 year round trip is probably our best bet.

Re:Radio

[snadrus]

Sounds like our best bet. Yet we've broadcasted TV since the 60s. Any chance the SNR made it there? If so, we can already conclude nothing there cares for '80s MTV.

Re:Radio

[Kagura]

I think you mean Star Wars.

Re:Radio

[Anonymous Coward]

We already did, though it was aimed at 581c, not 581g, but it seems to me that'd be "close enough" for any intelligent life to pick it up.

Re:Radio

[jgagnon]

Can stdout be redirected in such a way? :p

Re:Radio

[Tablizer]

How about sending some targeted "Hello world" transmissions towards that object first?

Syntax Error in Line 1: communication aborted.
Missing opening semi-parenthicolon.
Ping Time: 47287291320923.52 seconds.

   

Re:Radio

[natehoy]

Yup, meaning if we wait ten years to send the radio transmissions, it'll be 50 years from now when we could possibly get a reply.

Aim a radiotelescope there, send a bunch of clear repeating signals for a couple of months, then in 40 years aim a radiotelescope back at the star and listen for a year or so. The chances of any possible success are incredibly low, but then again so is the cost.

Then work like hell to outrun those radio signals, of course. :)

Re:Radio

[Anonymous Coward]

Damn snobs!

Re:Radio

[ss122_ry]

Wikipedia suggests that a radio signal was sent in 2008 to the planet Gliese 581 c. http://en.wikipedia.org/wiki/Gliese_581#Radio_signal_sent_from_Earth Now we just have to wait until 2048-49.

Re:Radio

[Tablizer]

Wikipedia suggests that a radio signal was sent in 2008 to the planet...Now we just have to wait until 2048-49.

I had a bad dream that I stayed in shape by eating boring food, exercising my tail off, skipping slashdot to go outdoors in order to live that long, only to have the reply be: "STFU!"

Re:Radio

[Tablizer]

I read somewhere that they might be intentionally ignoring us until we develop warp capability.

Or because of Jerry Springer
   

Re:Radio

[Wingsy]

If I've said this once I've said it a thousand times. Radio communications is simply a passing fancy for advanced civilizations. They don't use it any more. It was only a viable means for communications for a few hundred years at most. What all the aliens are using now are UHF (and higher) gravity waves. Not blocked by anything.

Re:Radio

[TheRaven64]

The speed of light depends on the medium. The grandparent was asking if light in a vacuum travels at the speed of light in a vacuum.

Re:Radio

[Surt]

In fairness, I would guess the ggp was probably unsure whether or not radio was light. After all, why not call it light? The answer? Because FM light sounds terrible on marketing posters.

Re:Radio

[geekoid]

So? 40 years is worth it. You create an automated system, once a month it send out a 12 hour 'beam' at the planet. Every month for 10 years. The just wait for a reply. Since it's would come from a very specific place, we can do it with just a few antenna. You could make it part of a automated computer that scan for a 'response' and them published the data online for others to look at.

Re:Radio

[JamesP]

Hello
(wait 40 years)
Hi
(wait 40 years)
Well Hi there
(wait 40 years)
How are you doing ?!
(wait 40 years)
Fine how are you
(wait 40 years)
Sorry what did you say!?! we lost it

Yes, it would not be very entertaining :P

Re:Radio

[blind biker]

How about sending some targeted "Hello world" transmissions towards that object first? If they have any intelligent life and a SETI program in place, they may hear us and answer back.

More likely, it would go somewhat like this: "Hey, we got a message from... that point there. Oh, an exoplanet, just perrrrfect for us! Let's warp there, kill/eat/analprobe/enslave those fools and live the life!"

Re:Radio

[sycorob]

That "whooshing" sound you hear is either mankind's first warp drive coming online ... or just the sound of the joke going over your head.

Re:Radio

[onkelonkel]

The radio around here has nothing but FM light. Light FM, Smooth FM, Silk FM, EZ FM, how many god damned radio stations does Michael Bolton need? "Es ist zum kotzen"

Re:Radio

[youn]

I think when they hear the quality of our tv programs/ radio transmissions, they may ignoring us because of bad taste :)... interstellar racism... they are only from sol after all :)

Re:Radio

[Quakerjono]

Or every John Hughes film ever made....IF THEY WERE SET IN SPACE. But don't worry. Our uniquely rebellious planet will learn that it has an inner strength and doesn't need that bitchy exoplanet's approval. As a sign, Earth will take two perfectly good prom dresses and rip them apart only to reassemble them in a Frankenstein's Monster creation resembling a cross between a potato sack and a straightjacket for Rainbow Bright. Then, after prom, Earth will bang Andrew McCarthy and this will somehow force Jon Cryer to star in a sitcom with the Sheen that didn't marry Paula Abdul. Yeah. That'll show 'em.

Re:Radio

[DigiShaman]

If you believe in extraterrestrial visitation, you'll notice that many sighting were made shortly after the first test of the atomic bomb on July 16th, 1945.

We know that the bomb is based on converting mass into energy. All that energy radiates at the speed of light. But what if there's other forms of energy generated at a different dimension that transcends space, time and the speed of light. What if that bomb was detected on an alien scanner millions of light years away...instantly. This would be important because of two things. Plutonium doesn't really occur naturally in such concentrated amounts if I recall. Second, getting that same plutonium to go super critical requires engineering. So when that bomb popped, it acted as beacon with a unique signature saying "Hey, there's intelligent life over here".

If all that turned out to be true (maybe, maybe not), Trinity was humanity making "First Contact".

Re:Radio

[Anonymous Coward]

How about sending some targeted "Hello world" transmissions towards that object first?

If they have any intelligent life and a SETI program in place, they may hear us and answer back.

And, the aliens on Gliese 581g - a planet poor in metals - after an epic, multi-generational effort managed to build a single radio telescope of sufficient size an succeeded in detecting and decoding a fragment of the messages sent by humanity, which said:

FROM THE OFFICE MR SULEMAN BELLO, AFRICAN DEVELOPMENT BANK (ADB), OUAGADOUGOU BURKINA FASO, WEST AFRICA.

TRANSFER OF ($ 25,200.000.00) TWENTY FIVE MILLION, TWO HUNDRED THOUSAND DOLLARS.

I AM SULEMAN BELLO, THE AUDITOR GENERAL OF AFRICAN DEVELOPMENT BANK HERE IN BURKINA FASO.
DURING THE COURSE OF OUR AUDITING, I DISCOVERED A FLOATING FUND IN AN ACCOUNT OPENED IN THE
BANK BY MR JOHN KOROVO AND AFTER GOING THROUGH SOME OLD FILES IN THE RECORDS I DISCOVERED
THAT THE OWNER OF THE ACCOUNT DIED IN THE (BEIRUT-BOUND CHARTER JET) PLANE CRASH ON THE 25TH
DECEMBER 2003 IN COTONOU (REPUBLIC OF BENIN).
[...]

Re:Radio

[holmstar]

Technically the signals will have propagated that far, but they would be so weak at that distance that it would be impossible to discern the signal from the noise.

Had we been tight-beaming the signal directly at them at 100 megawatts, then yes, they would possibly have a chance at noticing the signal, but not the way that we broadcast it.

Re:Radio

[holmstar]

Alternatively, we tight beam a signal for a few months, and almost exactly 20 years later an alien fleet suddenly appears in the solar system (the aliens having figured out how to tunnel from point to point without crossing the intermediate distance).

Communicate first?

[earthloop]

Would it not make sense to communicate first? Radio at 20 light years is a 40 year round trip. You never know, somebody might answer with instructions on how to get there quicker.

Hey! That's given me an idea for a great film. Is Jodie Foster available for the lead?

Re:Communicate first?

[boarder8925]

Would it not make sense to communicate first?

Provided that if there is life out there, and if it's intelligent, said life can understand any of our languages, or would care to take the time to figure out what it meant.

Re:Communicate first?

[SheeEttin]

Actually, we did send a radio signal--but it was to Gliese 581 c.

Actually, that brings up a question--when they transmit these messages, do they lead the target, aiming for where it should be in 40 years, or just blanket the system?

Re:Communicate first?

[Target Practice]

... and that said intelligent life didn't want to eat us crunchy humans for breakfast. I'm all for blaring out "Hey, we're here!" after we determine what they like with their toast.

Re:Communicate first?

[Anonymous Coward]

That also solves the traveling problem. If we could link there internet with ours, you could just book a ticket on a traveling site on there internet, and they would come and get you. (Unless they can't run a profit on short flights like Earth - 581g.)

Re:Communicate first?

[MoonBuggy]

Interesting link - I like the idea of getting people interested through the public competition, but in reality that's all it is, a publicity stunt. I hope they spent a while broadcasting a simpler signal as well - prime numbers, simple repeating patterns, something like that. Think of it from our point of view: would SETI really pick out something like a digitally encoded image, using an alien data transfer scheme, from random data? I doubt it. Recognising a sequence of primes, or squares, or some such, whatever numerical base they were transmitted in, is much more plausible.

Re:Communicate first?

[suso]

Actually, that brings up a question--when they transmit these messages, do they lead the target, aiming for where it should be in 40 years, or just blanket the system?

Actually a better question would be why did they only send it for one day. I would think you'd want to build up a heck of a lead time, like maybe a countdown of a year that shows when the important part of the signal would be transmitted. Otherwise, you'd likely waste the effort on transmitting a short message that arrives on New Glieseyear Eve and nobody is paying attention.

According to the link you provided, they only sent it on one day. Why?

Re:Communicate first?

[jgagnon]

Unless, of course, they are vegan aliens. Besides, most of us are too fat for use in a balanced diet.

Re:Communicate first?

[immakiku]

Assuming they have the technology to travel much faster than we can, they likely also have the technology to detect "Gliese 581g-like" planets. In other words, they probably already know about Earth, and probably already know about humans. It would be conceivable that they've already traveled here. Why send a message to their home planet when you can just indicate an interest to learn right here in our solar system? Latency: 1 second.

Re:Communicate first?

[dbosso]

You never know, somebody might answer with instructions on how to get there quicker.

Yea right, and a recipe for the sauce we're to pour on our bodies upon arrival.

Re:Communicate first?

[vlm]

Actually, that brings up a question--when they transmit these messages, do they lead the target, aiming for where it should be in 40 years, or just blanket the system?

I do some microwave RF work. The two words you don't know to google for are "proper motion" and "beamwidth". I think you have either vastly overestimated the "proper motion" of the nearby stars, which tops out around 10 seconds of arc per year, or vastly underestimated the beamwidth of our antennaes, which maxes out around that on our largest scopes at their highed frequencies. Effelsberg class radio telescopes are not exactly a dime a dozen and using their highest RF frequency is not necessarily a great idea due to adsorption issues both in our atmosphere and interstellar media.

http://en.wikipedia.org/wiki/Proper_motion

http://en.wikipedia.org/wiki/Effelsberg_100-m_Radio_Telescope

But its still a good first approximation that the best radio telescopes in the world are just barely at the level where their beamwidth is relevant to proper motion problems. Just barely....

Re:Communicate first?

[schmiddy]

Hrm, any radio astronomers out there? How hard would it be to rig up a poor man's directional radio antenna powerful enough to send a clear signal to that planet?

Re:Communicate first?

[SilverHatHacker]

You never know, somebody might answer with instructions on how to get there quicker.

In three-point-five light years, turn left...

Re:Communicate first?

[geekoid]

We can devise a simple code. Using information you would need to know by anyone capable of picking up the signle. Math works. If memory serves someone has already done that...

Re:Communicate first?

[Punto]

this sounds like the kind of cheesy thing where they send pictures of a bunch of ethnic kids holding hands. it'd be interesting to send something like a sequence of pulses indicating prime numbers or something like that, which can easily stand out from random noise. Also, keep transmitting for a long period of time, they might not be listening.

Re:Communicate first?

[vlm]

Hrm, any radio astronomers out there? How hard would it be to rig up a poor man's directional radio antenna powerful enough to send a clear signal to that planet?

Check out J.D. Kraus "Radio Astronomy" from your nearest library or pdf sharing website.

Its towards the end. You'll be disappointed. Its one of those situations where if you have to ask how difficult or expensive, then trust me, its way too difficult or expensive for you. On the other hand, its possibly within the range of major university program or maybe a religious cult.

You'll see modulation (or lack thereof) plays a big part, along with adsorption issues.

To a ridiculously crude first approximation, take a planetary radar, and maybe multiply its range by 10 since you get a factor of 2 by not bouncing back and at least a factor of five because you're not relying on reflectivity. So, planets in our solar system are no problemo, but alpha centauri would be quite a noteworthy achievement.

Re:Communicate first?

[Anonymous Coward]

I hate to plug Cosmos on slashdot, as Carl Sagan is the closest thing to a deity slashdotters have, but he explained this pretty well. We could easily send a pulse of a fundamental constant's value. If they have the ability to build a radiotelescope to pick up our submission, they're competent enough to decode it. If we were encoding pi, we'd send three pulses at a certain frequency (or a few frequencies), followed by a longer pause, then one pulse, and so forth...

In any language, this would be understood. Even if the aliens are using base 39, they'll see only 10 distinct values in the transmission and consider the number's value in their base, where someone will recognise it. The only issue I can really think of, assuming this signal successfully traverses space and is received, is that perhaps the alien world works on a vastly different timescale, where such a seemingly short/long burst of information is considered background noise. Even so, it'd be hard to miss due to the signal spikes at certain frequencies

Re:Communicate first?

[agw]

So, you want send "3.14.." to the Vl'h"urg on Gliese 581? "Unfortunately, in the Vl'h"urg tongue this was the most dreadful insult imaginable, and there was nothing for it but to wage terrible war for centuries."

Re:Communicate first?

[Anonymous Coward]

Not only that but we should be pointing our antennas at it looking for signals already there. I wonder if there is any way to determine how old the planet is. If it had a similar development cycle to the Earth then they also could have been putting out radio signals for the last 100+ years.

Re:Communicate first?

[Anonymous Coward]

It's statistically improbable that there isn't "life out there". Whether said "life out there" is intelligent or not is another matter. If I detected an extraterrestial signal on my IO device of choice on a clear starry night while star gazing, I'd try hard to figure out what it meant.

 

Re:Communicate first?

[Anonymous Coward]

We already sent one transmission apparently. link

Re:Communicate first?

[Jappus]

Would it not make sense to communicate first?

Provided that if there is life out there, and if it's intelligent, said life can understand any of our languages, or would care to take the time to figure out what it meant.

I think there's an easy answer to that: Wouldn't we try? Don't we already search for it? Haven't we tried coming up with ways to make understanding easier [1][2][3]?

If there is intelligent life out there, it will surely look nothing like us and most likely think in wholly different ways. But whatever they do, if they have ever gone to the length to discover radio, don't you think that one of the prerequisites to that is trying to find out why you can't send on a particular frequency as well as on others, because it's blocked by another, albeit weak, signal?

Of course, if they don't exist, or can't receive or even can't understand it after all, what have we lost by sending it in the first place?

[1] - Voyager Golden Record
[2] - Arecibo Message
[3] - Lincos

Re:Communicate first?

[boarder8925]

I wasn't saying we shouldn't try, but that we shouldn't put all our efforts into communicating at the sake of developing technology to go. By all means, beam signals out there! But don't let the development of travel technology atrophy--we won't have lost anything but the chance to get there.

Re:Communicate first?

[boarder8925]

As to "statistically improbable," see Fermi paradox. As to your example of detecting an extraterrestrial signal, yes, you would try to figure it out, I would try to figure it out, but that doesn't mean that some creature in the far reaches of space would care to. What's intriguing to us could just be noise to him.

Re:Communicate first?

[holmstar]

Presuming you did manage to cobble together some sort of antenna, the problem is that you still would need to power it. Unless you have an industrial level grid connection, you aren't going to be able to home-brew an interstellar message.

Re:Communicate first?

[Matthew Dunn]

I don't have the math handy but I've worked it out before -- when various groups send 'messages' into space from earth --- there's no realistic expectation another species will be able to receive it...we have trouble receiving massive, massive, EM sources that are millions of gigawatts at that range. We typically only do these' transmissions at thousands of watts at most.. They just hope that the alien species has some kind of super advanced receiving method....but most likely to receive a transmission from earth at that range would require a collection area like a parabolic dish the size of a planet. So even communication is unlikely.

Even if you could...

[vistapwns]

make a ship that contained the necessary fuel and so on to get there in one human life span, vital systems in the ship would almost certainly malfunction and the crew would be stranded until they died or something. People need to realize the only way we're getting off this rock is with nanorobotic manufacturing. Nanorobot constructed ships would be smart, and self-repair, fixing any problem that arises. If congress would dedicate a small fraction of that $25 billion NASA is getting to study rocks in outer space to nanorobotics, we'd get indefinite life-spans, space ships that could travel to the Andromeda galaxy never mind a star 20 light years away, an end to poverty, disease, crime, and so on. I suggest everyone read "Engines of Creation" by Drexler, it's free to read and posted on the web. http://e-drexler.com/d/06/00/EOC/EOC_Table_of_Contents.html

Re:Even if you could...

[CohibaVancouver]

Nanorobot constructed ships would be smart, and self-repair, fixing any problem that arises

Human-constructed ships could be crewed by humans, fixing any problem that arises.

Re:Even if you could...

[nschubach]

Yeah, but there's that whole risk thing... can't put a human in a suit every week and risk them getting hurt if you only have a few on board.

I don't think nanobots are going to be as huge as the OP, but it is cool to think about.

Re:Even if you could...

[wjousts]

Sorry, but babbling a bunch of science fiction fantasies doesn't make it so.

Re:Even if you could...

[jandrese]

Nanomachines can only do all of that stuff because you haven't thought through the problems yet and realized the limitations. How you power a machine that small, or make it intelligent, or give it sensors, or pretty much anything is still a lingering question. Once you get past the sci-fi aspects, nanomachines start to look depressingly limited. Self replicating nanomachines are especially nutty, given how complex such a device would need to be.

Re:Even if you could...

[vistapwns]

You'd have to have two space ships basically, one for spare parts. And what happens if one particular part breaks 3 times? or 20? Over the course of years, in a hostile environment like space, you have to assume that will happen. Nanorobots will fix things by constructing spare parts out of raw materials (atom feed stocks, like large stores of carbon, etc. so the parts need not be stored.) But you knew this right? I mean you're not lecturing me on nanorobots without having a clue about the mechanics of such things, RIGHT?

Re:Even if you could...

[vistapwns]

Do you have a real argument, because it seems to me you are the only one babbling. (well maybe the guys who think we're getting 20 light years from here in something equivalent to an apollo rocket as well.)

Re:Even if you could...

[vistapwns]

Well I guess we'll never know because thanks to people like you it won't get funded probably ever, meanwhile we'll spend billions testing plant compounds to see if they can cure cancer and give people 10 extra years of life. How forward thinking.

Re:Even if you could...

[wjousts]

Do you have a real argument, or do you just have blind faith in magic pixie dust and unicorns? All your nanorobot nonsense amounts to nothing when nobody has yet managed to build such a thing. You'll get your nanorobots when I'm commuting to work on my jet pack.

Pretending that there aren't major engineering obstacles in the way and thinking that just throwing money at it is the answer is not productive.

Nanorobots are some magical panacea that will solve all our problems.

Re:Even if you could...

[vistapwns]

If throwing money at the problem is not going to fix it, what will? Wishful thinking and wasting the money instead on bullshit that is barely or not at all helpful?

"Major engineering obstacles" is meaningless, everything high-tech has major engineering obstacles, especially to people who don't understand the field.

| Nanorobots are some magical panacea that will solve all our problems.

Freudian slip? But since nobody says they will solve ALL problems I should not even bother replying, they will just solve many pressing problems and are definitely worth funding/building. More so than just about any other endeavor that we spend billions on.

And a jetpack would be an easy device to make with nanorobotics, so yes you will be commuting to work when I get nanobots.

Re:Even if you could...

[Zenaku]

At present, discussing the mechanics of nanorobots is like discussing the biology of sharktopi.

Re:Even if you could...

[vistapwns]

Not really. We don't know everything about them but we know a lot (we'll people who take time to study the field do, not average lay people, which is obvious from the other posters in this thread.) Anyway this thread is degrading into a contrarian contest of "yes it will", "no it won't", "yes it will", etc. so I'm probably going to go do something useful.

Re:Even if you could...

[wjousts]

they will just solve many pressing problems and are definitely worth funding/building.

No. They don't solve any problems because they DON'T FUCKING EXIST. You seem to miss that rather important point in your zeal to espouse the amazing properties of something that is purely fictitious and hasn't even been demonstrated in principle. Funding it doesn't help if it's actually impossible.

It does not follow that just because something can be imagined that it can be built.

Re:Even if you could...

[immakiku]

Steam engines used to not solve any problems because they didn't exist. I guess people should never have researched the abilities of steam engines.

What I like about vistapwn's viewpoint is that he is coming up with potential solutions. Yes it's farfetched given our current understanding of the world, but with our current understanding of the world, this idea is one member of a very small subset of POSSIBLE solutions. We see a target. We should aim for it even if it turns out to be a mirage.

Re:Even if you could...

[wjousts]

I'm not saying don't do research. I'm saying demonstrate the technology before you go running off with how it's going to solve every problem (or at least a whole bunch of problems). Before the invention of the steam engine people weren't running around talking about how revolutionary it would be if somebody would just invent it first.

vistapwn isn't coming up with potential solutions, (s)he's doing the equivalent of suggesting if only we had magic pixie dust.

Re:Even if you could...

[pclminion]

Our bodies are made of self-replicating nanomachines. Stragely enough, these machines come pre-made with a general purpose programming language called "DNA." Perhaps instead of attempting to start from scratch we should try to adapt what we are already surrounded by to fit our purposes better.

Re:Even if you could...

[jandrese]

For the purposes of these discussions, cells are generally considered to be much too large to be counted as "nanomachines". Still, they are a good example of what is capable with nanotechnology. Unfortunately, we don't have any good examples of organic beings capable of operating in deep space. Well maybe that's fortunate since I really wouldn't want to be in a real life Zerg Rush.

Re:Even if you could...

[david_thornley]

Self-replicating nanomachines were developed hundreds of millions of years ago, and by now this whole rock is practically covered with them. It did turn out to be necessary to combine them to form larger machines to give them decent sensors and even basic intelligence., but even the smaller versions have solved the power problem.

You are correct, but

[dreamchaser]

You are correct, but just a mere few hundred years ago the fastest we could move was a dozen or so miles in a day. I am optimistic that if we don't manage to destroy ourselves we'll find means of providing energy and types of propulsion that would seem like magic to us today (kudos to A.C. Clarke for the reference).

Re:You are correct, but

[Anonymous Coward]

A few hundred years ago, people were riding horses and moving much further than "a dozen or so miles in a day". AFAIK, this has been true for all of recorded history.

Re:You are correct, but

[jandrese]

I don't think you understand the magnitude of the problem. These are fundamental physical limits of mass and energy we're talking about. Literally the only chance we have of getting to another solar system is to discover an entirely new branch of physics that somehow makes interstellar travel feasible. Probably the best bet is to copy it from visiting aliens, if any ever bother to visit.

Re:You are correct, but

[elrous0]

Probably the best bet is to copy it from visiting aliens, if any ever bother to visit.

I guess it would be nice to probe THEM for a change. And we could always use a baited field to lure them out. I suggest a trailer park filled with meth-addled hillbillies.

Re:You are correct, but

[IndustrialComplex]

Probably the best bet is to copy it from visiting aliens, if any ever bother to visit.

Meanwhile in a neighboring star system,

"Probably the best bet is to copy it from visiting aliens, if any ever bother to visit."

Re:You are correct, but

[LordSnooty]

No wonder our universe is so backward... all the civilisations are sat in their gravity wells waiting for someone else to turn up with a solution....

Re:You are correct, but

[Facegarden]

In the last 110 years, we did discover an entirely new branch of physics. We keep noticing funny things that make it seem like that will happen again. We've got dark energy and string theory, and we have almost no idea how gravity works.

I have a feeling that if we keep building particle accelerators, and playing with fusion and building better machines, we'll discover some new process that allows us to travel very, very fast within the next 500 years.

Humans as a whole are amazingly intelligent. If we don't blow ourselves up or exhaust our economies of science funding or destroy our schools to the point where no one knows science, I could see it happening in the next 500 years.

And honestly, you can't tell me I'm wrong - it's the fucking future and this is rampant speculation anyway. I've read a Brief History of Time, watched the COSMOS series, and thought for hours on end about the vastness of space and the insane complexity of interstellar travel, so I know enough to at least be part of the conversation.

But I could see it happening.
-Taylor

Re:You are correct, but

[Anonymous Coward]

Only four years before they mapped the earthworm genome it was thought that it wouldn't be possible to do such a thing.
A few years later they were mapping the human genome.
It's better to be optimistic and be disappointed, than to be pessimistic and not try.

Re:You are correct, but

[mangu]

These are fundamental physical limits of mass and energy we're talking about.

A little over a hundred years ago we knew nothing bout these fundamental physical limits.

I agree that, according to our current understanding, speed of light seems absolute enough, but our experimental results aren't that absolute. We have never propelled anything bigger than a molecule to any speed close to the speed of light.

Our knowledge about the speed of light limit comes mostly from thought experiments that get results that contradict causality. However, causality and the unidirectional nature of time is a thermodynamic effect. Subatomic phenomena are time-reversible.

For now, I would like to consider some options still open on faster-than-light travel.
When one starts doing thought experiments, one can get paradoxal results that contradict relativity as well. The Andromeda paradox for instance indicate that, if relativity is right, then the future is predetermined, since two observers moving at different speeds will have different opinions on what is happening in a distant place.

Re:You are correct, but

[bjb_admin]

I believe the aliens think this propulsion method is based anal probing, considering the legacy left "behind" by their past visits.

Re:You are correct, but

[blueg3]

Normal walking is 20+ miles in a full day. On horse, it's more like 50 miles in a day. Now, in the same amount of time, you can travel 10x that by car or nearly 100x that in an airplane. The speed of satellites and orbit and such is on the order of hundreds of times the speed of a car (or tens of times the speed of an aircraft).

Re:You are correct, but

[Wyatt Earp]

During the age of sail, a ship could travel 12-20 miles per hour easily and do that all day long.

A horse with a rider can travel 30-50 miles a day with proper water and feed, a camel can do 40-60

Re:You are correct, but

[Anonymous Coward]

Only people with serious physical disabilities can't walk at least forty miles in a day. A fit marcher doing a long, hard march should quite reasonably be able to do eighty miles, although that certainly couldn't be an every day event. Sure it's tougher without roads, but we've had roads for what, at least 7,000 years? Let's also not forget about people using boats and taking advantage of wind, currents, or water flow in rivers. People have fairly obviously been managing hundreds of miles in a day (though obviously not always reliably) for all of recorded history.
It's amazing how little thought people put into these grandiose statements. It reminds me of claims that traveling faster than you could on horseback would prove fatal from way back. A few minutes reflection should be all it takes to realize that cliff divers, skiers and the like had been traveling at far greater speeds for a long, long time.

Re:You are correct, but

[MoonBuggy]

And a bog standard passenger jet can get you pretty much anywhere on the planet within a day. A fast military jet can do the same in an afternoon. The difference over the past century is orders of magnitude.

Re:You are correct, but

[poetmatt]

technology is only going to advance further. I wouldn't doubt that interstellar travel will become feasible, it's just a question of when and how.

Re:You are correct, but

[T Murphy]

kudos to A.C. Clarke for the reference.

How dare you call Clarke an anonymous coward!

Re:You are correct, but

[Wyatt Earp]

Jet speeds have been stagnant for about 50 years, reliability and fuel efficiency have gotten better, but speed hasn't.

Hell, military aircraft top speeds are falling off. The Mach 2.5-3+ aircraft like SR-71, MiG-25, MiG-31, XB-70 just aren't being built anymore.

Do you really see Mach 5-6+ aircraft being the military norm by 2050-60? I don't see it, F-22, F-35, Typhoon are going to be where the F-15 is now.

Likewise, theres nothing to suggest civilian aircraft are going to be supersonic by 2050. That's just a doubling, nothing points to military aircraft being orbital or suborbital and Mach 25 by 2050-60

Re:You are correct, but

[jgagnon]

Are you assuming fair seas and flat land? Also, "proper water and feed" is a built-in gotcha. Having done some backpacking recently, I can that a 20 mile day while carrying your essential gear and supplies is a very long day. Sustaining that pace while maintaining your supplies of "proper water and feed" would be problematic at best.

Re:You are correct, but

[CrashandDie]

"I don't think you understand the magnitude of the problem." Banks told Cook, "There are fundamental physical limits to the amount of food we can take and the amount of money available to either of us."

Cook wasn't really listening, just looking through the window, already enamouring the feel of the audacious idea. Seeing his friend take but little to no appreciation from his words of warning, Banks continued.

"Literally, the only chance we have of finding another continent is to build an entirely new ship that somehow makes this kind of journey feasible. Probably the best bet is to copy it from the Dutch, if any ever bother to visit."

The fire kept glowing steadily as they both stood, looking outside the window. Neither of them knew how wrong they were in their expectations.

Re:You are correct, but

[vlm]

I agree that, according to our current understanding, speed of light seems absolute enough

Also according to our current collection of experiments, as far as I know.

but our experimental results aren't that absolute.

Yet the end of your quote tantalizingly hints that you know of or possess experimental evidence that it is not. Care to share? Extraordinary claims require extraordinary proof.

Re:You are correct, but

[JustOK]

wrong type of worm

Re:You are correct, but

[MoonBuggy]

I think we're looking at the issue differently. I was thinking more of the major breakthroughs that caused significant jumps (at least once they were past the teething problems), rather than the refinement of those technologies for a little more improvement.

Think sails (order 10mph) -> internal combustion (order 100mph) -> jets (order 1000mph) -> ? (order 10,000mph).

Obviously I don't know whether we're going to manage to fill in that '?' on the end, nor do I know whether the relatively short gap between the advent of internal combustion and that of the jet was just a fluke, but if history's taught us anything it's that we're good at coming up with things that previous generations couldn't predict!

Re:You are correct, but

[Anonymous Coward]

"Probably the best bet is to copy it from visiting aliens, if any ever bother to visit."

Damn! Aliens with that kind of technology also have the internet, man! Now they'll be on to us!

Re:You are correct, but

[Wyatt Earp]

I think it'll happen, we seem to be on the verge of a hypersonic and orbital spaceflight break through.

But it feels like technology adoption is slower now, we aren't going to thrown away 737s and 787s for hypersonic like we dumped DC-4s when jets came long.

Re:You are correct, but

[Tablizer]

Probably the best bet is to copy [fast engines] from visiting aliens

How can we when the feds keep locking it up at Area 51!
   

Re:You are correct, but

[0xdeadbeef]

I've read a Brief History of Time, watched the COSMOS series, and thought for hours on end about the vastness of space and the insane complexity of interstellar travel, so I know enough to at least be part of the conversation.

Yes, but have you watched the History Channel's The Universe series, and the BBC documentaries by Brian Cox? We need to make sure your education has enough loud explosions and dippy old hipsters to participate in this conversation.

Re:You are correct, but

[Anonymous Coward]

Quote heard a few hundred years ago:
"I don't think ye understand the magnitude of the problem. These are fundamental physical limits of mass and energy we're talking about."

When the best you can do is cross land on horseback and crossing and ocean is still unknown science, the ability to reach space and what actually exists there probably seemed similarly unachievable.

Re:You are correct, but

[shoehornjob]

"Probably the best bet is to copy it from visiting aliens, if any ever bother to

I have a hard time thinking that a secies more advanced than us would give/sell their technology. Maybe if we stopped trying to kill each other and live in peace that could happen but I aint holding my breath.

Re:You are correct, but

[TheRaven64]

The big limitation, aside from the requirement that the human inside survives, is atmospheric drag (which plasma torches go some way towards reducing). Around mach 5, ionisation and other effects make things very difficult, and ramjets no longer produce acceleration. This is a similar engineering challenge to mach 1. If you can go at mach 6, going at mach 10 is not a significant engineering problem. If you can go at around mach 5, going up to mach 6 is - unlike the jump from mach 1 to mach 5, it's not just a matter of energy density.

This does not apply in space, so an ion drive can easily reach very high speeds, although mach does not apply as there is nothing to transmit sound.

Re:You are correct, but

[dpilot]

Then there's the other way...

Well before we have a fraction of the technology necessary to ship our "ugly bags of mostly water" to another star, we'll likely have hit Kurzweil's Singularity, and most notably the ability to extract and run a Turing image. Even if the computer necessary to run that Turing image is the size of a human body, its "life support" will be electricity and temperature control, the hardware can be slowed down during the boring parts of the journey, it can likely stand higher accelerations than bio-bodies, etc, etc, etc. All told, interstellar exploration by Turing images may well be far more likely than bio-bodies. It wouldn't surprise me that not long after we succeed at extracting and running a Turing image, we'll have interstellar capability for those images, even though we'll be a long way from doing so for bio-bodies.

Of course whether we first do that or render Earth unfit for advanced civilization is anyone's guess. (Environmental collapse rendering the planet nearly uninhabitable for millennia is not uncommon in geological time. The Earth has always recovered - in a few thousand to a few million years.)

Re:You are correct, but

[vlm]

Hell, military aircraft top speeds are falling off. The Mach 2.5-3+ aircraft like SR-71, MiG-25, MiG-31, XB-70 just aren't being built anymore.

Attention shifted from making faster aircraft to making faster missiles.

Chart A/A A/S and S/A missile performance, both speed and range (and to a lesser extent, payload).

It's a stylistic change to put your performance in missiles instead of planes, its not like aerodynamic knowledge of flying fast is being lost.

Re:You are correct, but

[shutdown -p now]

Actually, the neighboring star system went:

"Before setting off to that place, make sure all the patents are current, and don't forget the DRM!"

Re:You are correct, but

[CatsupBoy]

Probably the best bet is to copy it from visiting aliens, if any ever bother to visit.

Probably that is the easiest bet. However, some alien somewhere would have had to come up with the concept on their own.

Instead of waiting for it to come to us, why dont we ignore the naysayers and keep plugging away with scientific research fueled by imaginative science fiction? Thats what brought us from the dark ages to today in pretty short time (cosmically speaking).

Re:You are correct, but

[Anonymous Coward]

I think if we could just come up with a propulsion technology that can do a constant 1G of acceleration (forever...), we're good. The floor of the human living quarters would need to be sitting horizontal to the rocket. Imagine the Enterprise with the saucer at a 90 degree angle to the nacelles. The crew then has built-in gravity... At the half-way point, you turn it off, turn the ship around backwards & then fire it up again for a 1G deceleration the rest of the way. This is the *only* way humans will ever be able to make interstellar travel possible/survivable from a physics standpoint. I would love to see the numbers, but I would guess that a constant 1G acceleration would start approaching high percentages of the speed of light in a year or so....

Re:You are correct, but

[Wyatt Earp]

I'm going to mainly look at US missile since I don't have the time to look at everyone's

A/A missile ranges have fallen off. Look at AIM-54 v AIM-120

S/A
MIM-14 - 90 mile range, MIM-104 PAC 2- 45-90 mile range

A/S
Cruise missiles are all in the 750km to 2000km range no matter who makes them (US/Russia/China/EU)

But look at HARM - 100km replaced AGM-78 Standard which had a 90km range.

JDAM and SDB are giving better stand off ranges, and guidance is much better, but the ranges and speeds of missile aren't increasing either.

Re:You are correct, but

[gumbi west]

Yeah, what if they are patent trolls and point out that most of their patents predate ours so all of ours are invalid. Then we are really screwed and we don't get the FTL without paying the license fee for it and everything else.

Re:You are correct, but

[loufoque]

No need for a new branch of physics.
The infamous Orion nuclear-propulsion design, which is more than fifty years old now, could reach 10% of light speed using thermonuclear explosions and up to 80% of light speed using matter-antimatter pulses.

Of course, there are probably engineering problems to make it feasible; but not really fundamental physics ones.

Re:You are correct, but

[eples]

Literally the only chance we have of getting to another solar system is to discover an entirely new branch of physics that somehow makes interstellar travel feasible.

At only 20LY away, it is entirely feasible that we could *ask* them. That is if there is a "them" on Gliese 581g.

Re:You are correct, but

[Teancum]

The difference between the aircraft fighters of the past and what we have now is maneuverability. Modern fighters can take some wicked corners and maneuver circles around some of those old aircraft like the classic U-2 or even the SR-71. Yeah, they can haul some wicked speed, but they need the entire western USA in order to do a 180 degree turn (or Siberia if they are doing recon missions).

The current limiting factor right now is merely the ability of the pilot to withstand those turns. Acceleration is the key now, not raw speed.

If there is going to be a need for speed, it will happen in space. Acceleration is still going to be key, but any new technologies are going to be worrying about how to sustain a large acceleration over a prolonged period of time. I presume that will imply something like nuclear rocketry (fission or fusion, take your pick) throwing mass out at a healthy fraction of the speed of light to give a very high ISP number. Such a rocket could in theory make it from Earth to Mars in a matter of weeks without having to invent new physics or having to discover a new scientific principle. All it would take is merely some tough engineering to pull off a ship like that and of course a huge pile of money.

In terms of military craft on the Earth, where do you want to go at Mach 6 anyway? Sure, you can go from New York to London in less than an hour with an SR-71, but what are you going to do in the hour after you get to London? Fly on to Moscow in the next hour? It doesn't serve any purpose to get to a target that quickly as once you get to that target you can't do anything before you literally move on and out of any strike zone to be useful in a dogfight or to support other military activities in that target area.

Re:You are correct, but

[Unsichtbarer_Mensch]

Progress is not always exponential: look at how speed of passenger aircraft has stagnated in the past 50 years...

Re:You are correct, but

[elrous0]

Sending men to another planet in our solar system is MUCH more analogous to a Columbus or Magellan style journey than any interstellar journey. We have boats probably capable or doing it (or at least plans for such boats), we done it before on a smaller scale, and doing it would only be a logical extension of what we've already done in sending men to the moon. Journeying to another solar system would be more analogous to Christopher Columbus going to Ferdinand and saying "I'm taking my sailing ships to Pluto tomorrow, I'll be back in a week."

Re:You are correct, but

[Wyatt Earp]

Maneuverability is the key right now in fighter design because from a design standpoint we are focused on ACM.

Take the Mach 6 fighter, what you'd do with it is on the outbreak of hostilities you'd use it to ARM and SDB the living crap out of your enemy's air defense network and then bomb the crap out of the enemy's airfields and C3 so that by the time the Mach 1-2 and subsonic planes get there theres nothing left that threatens them.

With speed and good missiles theres no need to dogfight. Yea, I know I'm using the 1955 to 1967 USAF/USN playbook there, but when you have missiles that hit and kill 70-90% of the time rather than 10-15% its actually a viable plan.

Look at the game plan for F-22, Typhoon and Rafale. Datalinks coupled with awesome radars and BVR missiles so you can kill the enemy before he can even get a radar return.

Re:You are correct, but

[green1]

Why 1G? seriously, it's what we're used to, but there's nothing to say that we couldn't adapt relatively quickly to slightly more. 1.5G would probably be quite workable, but would substantially decrease the amount of time required to reach the speed of light.

Of course as for "only" way... all I can say is, "for now". I can't believe how arrogant people are right now that they truly believe that humans know enough now to forever rule out not only faster than light travel, but also any other way to shortcut the distance. I think we should all know by now how many amazing leaps of knowledge and technology have happened since humans first picked up a stone or stick as a tool, and should know that believing that we will NEVER do better than we can right now is arrogant in the most extreme.

Re:You are correct, but

[geekoid]

Why would you assume if aliens could do it, we couldn't?

Your right, it isn't ever likely to happen. Maybe if we gert colony ships. Or automated cloning facilities.

It alway bugs me that people somehow think it it's possible, we couldn't do it.

It's really about potential energy density.

Re:You are correct, but

[JamesP]

Of course no one knows what's the reaction of people (even consenting ones) when stuck in a computer 'body' for ever...

Re:You are correct, but

[geekoid]

Rapture^H^H^H^H^H^H zombie apocolypse^H^H^H^H^H^H^H^H2012^H^H^H^H Singularity.

Kursweil is a whack-a-loon who hasn't actually added anything in decades.

Re:You are correct, but

[green1]

Jet speeds currently are not restricted by technological limitations, but political ones.

Nobody is building a supersonic passenger jet, not because it's impossible, but because no country will let you fly it over their airspace.

The high speed military jets aren't being built anymore because they've been superseded by satellite reconnaissance.

This has nothing to do with technology stopping us, it's all because of a lack of use for the technology. Space travel is a different problem with different political issues (mainly funding) however to state that because we've stopped increasing the speed of jets that we're not able to build faster spacecraft seems a little ridiculous. in fact one of the reasons we've stopped improving the speed of the military jets is precisely BECAUSE of advances in space flight!

Re:You are correct, but

[Anonymous Coward]

The faster than light travel problem combined with a space program centered around rockets has led to very "in the box" thinking on this subject.

Why not engineer around the problem and use a series of mass drivers like in "Lost in Space"?

By sending autonomous robots ahead of us to assemble fuel depots: we can slingshot to the destination.

Re:You are correct, but

[Delarth799]

Just the other day I was talking to my buddy from a few stars over and he said that he would be willing to sell us the technology for a mere 12 parsecs

Re:You are correct, but

[jandrese]

The fundamental physics problem was mentioned in TFA! Namely that you would need to bring 530 times as much fuel as the mass of your craft to make it there with the antimatter Orion engine.

Accelerating a human scale ship (it will be big) up to any discernible fraction of c with conventional explosions requires an absolutely staggering amount of energy, orders of magnitude more energy than have ever been created on Earth. The scale of the problem is staggering, it would be by several orders of magnitude, the largest project ever undertaken by Man--even counting massive projects like the federal highway system.

The only possible scenario where something like this would even have a ghost of a chance is if aliens showed up in orbit and said "In 500 years we are going to blow up your sun to make room for an interstellar bypass, and here's proof", and the entire economy of the world suddenly shifted towards getting people out to some other solar system. Even then it's doubtful that we would make it.

Don't get me wrong. I'm not saying it's entirely hopeless. Just don't get all starry eyed about visiting other planets. The cold hard reality is that there is nothing on the radar that would make it even vaguely practical anytime in the foreseeable future. Maybe ramscoops, but who knows what the odds are on those panning out. And sorry, even if there were some tremendous scientific breakthrough tomorrow, it would almost certainly not going to be ready for actual use in your lifetime.

Re:You are correct, but

[Anonymous Coward]

Humans as a whole are amazingly intelligent.

Er...no.

Re:You are correct, but

[ElectricTurtle]

Yeah, that whole instant verbal translation thing is totally worthless. Who wants a universal translator anyway when we could just continue to live insular, uncultured, ignorant lives? Good plan.

Kurzweil has done more for human progress than you likely ever will. You're probably jealous and express that jealousy through baseless hatred. Have fun being a douche.

Re:You are correct, but

[Anonymous Coward]

And it was modded Funny there too!

Re:You are correct, but

[Wyatt Earp]

F-15, FB-111, MiG-25, MiG-31 are Mach 2.5+ aircraft which were not reconnaissance. XB-70 was a Mach 3+ bomber that reached the advanced testing phase.

F-22 is not (openly) a Mach 2.5 aircraft so it's not as fast as the aircraft it's replacing.

It has nothing to do with reconnaissance satellites.

Re:You are correct, but

[Anonymous Coward]

It saddens me a little inside to see the just how much Physics kills curiosity.

As someone who does understand the magnitude of the problem, I'd like to point out the we have yet utilize the vast sources of energy surrounding us, to our advantage. And no. I'm not talking about Coal, Nuclear, Solar or Wind power generation.

Point is, until we become masters of this planet, speaking of fundamental limits on what is possible in the Universe is short sighted.

Mans abilities are only limited by the Universe. Did you ever consider that what physics we observe naturally, isn't all there is? And no, I'm not talking about Dark Matter, or Dark Energy. We are a product of this Universe, are we not? Perhaps 'we' can become a force of nature. Something yet to be defined?!?

I know. A little too fantastic to think we could evolve beyond this planet, and our current understanding of 'Physics'.

Re:You are correct, but

[Anonymous Coward]

The problem was figured out in the 50s using nuclear propulsion.

http://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)

I don't buy it. We have the resources for interstellar travel. It's naive to think it's impossible because it doesn't fit within the scope of your lifetime
or will take more than 6 months to get there.

Re:You are correct, but

[Scragglykat]

I don't think you understand the meaning of "magic." :o) Sure, we currently believe there is no way to do it... but I'm sure we are doing many things today that we would have thought impossible in the 50's even. The problem with our understanding of physics is that we don't fully understand all of it.

Re:You are correct, but

[modmans2ndcoming]

damned lazy liberal species!

Re:You are correct, but

[Unkyjar]

Here's an old article on an experiment that suggests that the speed of light may not be constant. Now as a disclaimer, I haven't followed up on this research, and don't know if they were ever able to repeat their results.

Re:You are correct, but

[modmans2ndcoming]

Reading that paradox reminds me of Zeo's Paradox. I have a gut feeling that the discovery of a new mathematics will show the fallacy in the paradox.

Re:You are correct, but

[modmans2ndcoming]

Excuse me... that should be ZENO

Re:You are correct, but

[idontgno]

What, lean out the window and politely ask for Grey Poupon and the secret of FTL?

I suspect their response would be something like "Oh. I was just about to ask you for the same thing."

Re:You are correct, but

[dpilot]

Assuming we can achieve a working Turing image, I kind of wonder how much time will be spent in virtual worlds and how much time will be spent in the real world, and for the latter how much human-mimic and how much some other sensory experience.

Re:You are correct, but

[Lanteran]

I don't know about you, but I'd prefer a mixed gender ship...

Re:You are correct, but

[idontgno]

Stagnation of engagement ranges for tactical missiles is less about technology and more about rules of engagement (i.e., politics and doctrine). Super long-range air-to-air missiles were about killing enemy aircraft before they could get over friendly territory. True in both the "continental air defense" mission and the "carrier group air defense" mission.

In practice, no one ever got to use those super-long-range AAMs because, frankly, rules of engagement didn't permit that kind of freedom. (Extreme case in point: During the Viet Nam war, U.S. air crews were forced to visually confirm hostile status of opposing aircraft before engaging. That's a little too late to FOX One, Wilbur.)

Similarly, I suspect that the cruise missile thing is a desire to keep these weapons on the "tactical" side of the "strategic/tactical" continuum.

No one is paying defense contractors to increase speed or engagement range, because those are not meta-requirements in the modern battlefield. Accuracy, constrained lethality (kills bad guys dead, leaves innocents completely alone), and asymmetry of threat (stand-off range, stealth, use of adverse conditions like night, etc.--anything that reduces the user's exposure to defense or retaliation) are much more valuable in the current friendly-risk-averse political environment.

Re:You are correct, but

[agw]

It probably makes more sense to increase the the thrust to go from 1.0 to the maximum save limit over the months of travel and then on the slow-down stop at the level of the target planet. If you're talking about periods of some sort of deep sleep while traveling, a few more Gs are probably ok while everything is strapped down. You just need a propulsion system that can alter the thrust quickly.

Re:You are correct, but

[green1]

I should have been clearer, satellites are ONE of the reasons, other reasons include:
- cost
- risk tolerance
- increased use of unmanned drones
- increased use of missiles
- increased focus on wars against slow moving targets with little or now aircraft of their own

but all of them are political, not technological.

Or are you trying to tell me that somehow what we did just a few decades ago is now physically impossible?

The point is that we are slowing aircraft down, not because we can't figure out how to make them faster, but because we've lost the political desire to have the high speed aircraft. this doesn't apply to space technologies in the same way because the political pressures are different (I'm not saying we DO have the political will to do it, only that the slowing of modern aircraft is completely irrelevant to the discussion of newer faster technologies)

Re:You are correct, but

[Joe Tie.]

It really is a weird assumption. As if any of us are making a hobby out of hooking up bark controlled shotguns to our dogs. We're a super violent xenophobic ape, it'd be illogical as hell to give that to us unless it came as a double package with genetic engineering for pacifism.

Re:You are correct, but

[Ol Biscuitbarrel]

Parsec is a measure of time, not currency. Duh.

Re:You are correct, but

[Anonymous Coward]

Literally the only chance we have of getting to another solar system is to discover an entirely new branch of physics...

Haven't we literally done that three times in the last century?

Re:You are correct, but

[Belial6]

You do realize that claiming there is no hard physical limit to speed isn't an extraordinary claim, but saying that there is a hard limit to speed is, right?

Re:You are correct, but

[SETIGuy]

The Andromeda paradox [wikipedia.org] for instance indicate that, if relativity is right, then the future is predetermined, since two observers moving at different speeds will have different opinions on what is happening in a distant place.

Like most relativistic paradoxes it's not a paradox at all. 'Now' is a term that should only be applied locally. Even once existence of the fleet in motion is seen, the observers will disagree about where it is, when it left, and how long it's been in transit. In other words a present that can't be seen is no more determined than a future that can't be seen or a part of the past that can't be seen.

It's primarily a problem of language not being equal to mathematics. We think of the future as undetermined, the past as concrete, and the present as the point where future solidifies to become past. Well, the undetermined and the concrete and the surface where they meet are all defined in relativity. They just don't correspond to the past/present/future definition we are used to. In relativity, we can't see any part of the future. We can only see a single point of the present, called "here". And the parts of the past that we can see and are determined are defined by light travel time. Anything outside of those regions we can see cannot affect anything 'now.'

It's not easy to visualize. For that you can blame four billion years of evolution where visualizing relativity was not a required survival trait.

Re:You are correct, but

[shoehornjob]

As if any of us are making a hobby out of hooking up bark controlled shotguns to our dogs.

Damn I've got to git me one of them. I love technology.

Re:You are correct, but

[khallow]

I don't think you understand the magnitude of the problem. These are fundamental physical limits of mass and energy we're talking about. Literally the only chance we have of getting to another solar system is to discover an entirely new branch of physics that somehow makes interstellar travel feasible. Probably the best bet is to copy it from visiting aliens, if any ever bother to visit.

This is nonsense. Keep in mind that another solution is simply to take a while to travel. For example, electric propulsion plus fission power can get us up to 0.01C (faster really, but we're not looking to go fast). That gets us to a target 20 lightyears away in a few thousand years. You don't need new branches of physics to do that.

Re:You are correct, but

[turbidostato]

"I have a hard time thinking that a secies more advanced than us would give/sell their technology. Maybe if we stopped trying to kill each other and live in peace that could happen but I aint holding my breath."

Klaatu barada nikto...

And then, for all the experience you have at hand, that surely would happen: "white people" had no problem selling guns to "red skins", so go figure.

Re:You are correct, but

[Anonymous Coward]

And we only knew about Newtonian Physics 150 years ago. How do you know it is impossible to discover another branch of physics?

Re:You are correct, but

[turbidostato]

"Parsec is a measure of time, not currency. Duh."

Maybe his friend was talking about a mortage. Duh.

Re:You are correct, but

[turbidostato]

"By sending autonomous robots ahead of us to assemble fuel depots: we can slingshot to the destination."

Out of what? Deep space is, well, quite empty.

Re:You are correct, but

[SwampChicken]

Parsec is a measure of time, not currency. Duh.

It's a measure of time to *us*.....but is a currency to them you insensitive clod.

Re:You are correct, but

[Nazlfrag]

They might be fundamental limits to our present day knowledge, yet we still can't explain over 90% of the apparent energy and mass in the universe (or reconcile classical and quantum forces) which seems to leave plenty of room for optimism.

Re:You are correct, but

[lennier]

As if any of us are making a hobby out of hooking up bark controlled shotguns to our dogs.

But you have to admit that would be seventeen different kinds of awesome.

Re:You are correct, but

[lennier]

Journeying to another solar system would be more analogous to Christopher Columbus going to Ferdinand and saying "I'm taking my sailing ships to Pluto tomorrow, I'll be back in a week."

Or like Lawrence Oates saying "I am just going outside and may be some time."

The kind of planetary economic bubble required to launch a manned interstellar mission with any expectation of commercial return before the end of the universe would be very interesting to observe - from a safe distance - as it collapsed.

Re:You are correct, but

[Nazlfrag]

Time means money in the world of intergalactic business.

Re:You are correct, but

[Anonymous Coward]

Not really true. A massless drive capable of achieving 1g continuous thrust could reach the closest stars in a much more reasonable time, on the order of thousands of years.
Still a long time, but not unfeasibly long.

At someone below's figures of a max of 3.3% of light speed, that gives 600 years. Even if you double that, its still feasible, for unmanned craft, or even cryogenics, if anyone would be crazy enough to sign up for 600 years of being frozen ;-0

Re:You are correct, but

[initialE]

In the movie District 9, DRM was used to keep alien technology out of human hands.

Re:You are correct, but

[Plekto]

Well, technically, we aren't looking for faster than LIGHT travel but faster than SPACE travel. We can't go faster than light, but we can perhaps shorten the distance. So what FTL travel will look like is nothing nothing nothing for a long time and then suddenly we can open wormholes/fold space to wherever we need to within range of our power source/device/etc.

I vaguely remember one science fiction show that also used that for teleporting, with one of the characters claiming that Trek-type teleporting was rubbish.

Re:You are correct, but

[ckurtm]

Probably the best bet is to copy it from visiting aliens, if any ever bother to visit.

Meanwhile in a neighboring star system,

"Probably the best bet is to copy it from visiting aliens, if any ever bother to visit."

Lol

Re:You are correct, but

[Anonymous Coward]

At one point, powered heavier than air flight simply couldn't work on the steam engines of the late 1800's. (Yes, there were some gliders, but they weren't much more than a useless novelty.) So claims that it were impossible were valid at the time. It took the Otto or Clerk cycle internal combustion piston engines to make airplanes a reality. Not only were the engines lightweight compared to steam engines, but the fuel payload became significantly smaller and you didn't need to lug all that water around to run a boiler.

Then getting the sound barrier was supposedly impossible. Not only was it aircraft design, but piston engines and props just couldn't do it. Not only that it was hard enough to get the RPMs up to provide thrust, but supersonic transitions on the actual prop blades causes their own unique problems. So it wasn't until the invention of the gas turbine jet engine that sustainable supersonic flight was possible. (Sure there was rocket power in the early development of supersonic flight, but that was a short one-shot deal.)

Now it's a fuel and reaction mass issue. We're stuck with rockets that turn fuel into the reaction mass, because there isn't much else in space to work with for reaction mass. Unfortunately, any alternate technology regarding inertia appears to be at an impasse. In other words, we're currently stalled on the one thing that could lead to the next big step.

Maybe we'll get lucky and the LHC or a similar project will crack that enigma (like finding some relationship between quantum physics or electromagnetism and whatever gives mass gravity and/or inertia), but then again maybe not. Somebody really should get working on that one, because in the long term sticking to one planet doesn't work all that great. (Well, not if your species would rather not end up like most of the dinosaurs.) Not only that, but the wanderlust is in our blood, we need to be able to go places. (And on top of that we're much like constantly breeding rodents kept in a cage with limited room and resources, right now we're getting crowded to the point where some of us are pooping in our food dish. Not a good thing.)

Re:You are correct, but

[0111 1110]

Actually a parsec is a unit of distance as the link you posted indicates. The amount of misinformation in these comments could power an improbability drive for millenia.

Re:You are correct, but

[Dr.Syshalt]

Probably the best bet is to copy it from visiting aliens, if any ever bother to visit.

And the first interstellar traveler will be a lawyer - traveling to the alien court on their planet as a defendant's attorney in patent infringement lawsuit.

Re:You are correct, but

[ZankerH]

There's no reason we should need faster than light travel to get to another star system. It makes it a lot more convenient, sure, but once you have enough energy to accelerate a ship to a significant fraction of c (and brake it at its destination), there's no reason you can't send a generation ship or a crew in cryo-suspension (once/if we figure that out, anyway) to travel for a few decades. It will make an "interstellar empire", and any notion of holding sovereignty over the other star system impossible, and the communications delay would be measured in decades, sure, but it's still a possibility, and a much more probable possibility than proving just about every physicist from the last 100 years wrong and inventing FTL travel, too.

Re:You are correct, but

[BitZtream]

These are fundamental physical limits of mass and energy we're talking about.

Assuming we're right in what we're calling fundamental physical limits ...

The arrogance of humans still blows me away, we think we actually know how things work ... even though just a basic glance at a history book will show you that we're wrong A LOT, we generally have never gotten anything 100% right, which means theres a really good chance what we think of as 'limits' are in fact not in any way a limit.

We have one group of brilliant people saying you can't exceed the speed of light, ever, ever, never, no way, can't be done.

Then we have another group of brilliant people saying that in fact during the big bang it happened.

One of those groups is wrong, throwing out a rather massive chunk of understanding about how the universe as we know it was formed.

Seems pretty reasonable that the silly things we call 'limits of physics' now are more than likely wrong as well.

Then you go ahead and throw in 'visiting aliens' ... because they some how manage to pull it off, but we can't? Thats just a retarded statement.

Re:You are correct, but

[Gilmoure]

There's a Niven short story where aliens visit earth and trade knowledge pills with us. Finally, someone gets a telepathy pill (side effect) and realizes humans need to start building an orbital launching device for the aliens. For cultures that can't do this, the aliens cause the sun to go nova and ride the shockwave on to the next likely star.

Re:You are correct, but

[operagost]

We're a super violent xenophobic ape

... with verb agreement issues.

Re:You are correct, but

[operagost]

Thanks, Captain Solo.

Re:You are correct, but

[Gilmoure]

As if any of us are making a hobby out of hooking up bark controlled shotguns to our dogs.

A hobby or a passion?

Re:You are correct, but

[Gilmoure]

As a kid, I waited long enough and WHAM! Anonymous, unlimited magic porn right to my bedroom. I love living in the future!

Re:You are correct, but

[ffreeloader]

You are correct, but just a mere few hundred years ago the fastest we could move was a dozen or so miles in a day. I am optimistic that if we don't manage to destroy ourselves we'll find means of providing energy and types of propulsion that would seem like magic to us today (kudos to A.C. Clarke for the reference).

Untrue, and provably so. Viking ships averaged 10 or 11 knots per hour. That's 12 to 13.2 mph, or approximately 144-160 miles in a 12 hour sailing day.

The better mustangs ridden in the Old West here in the US could do 100 miles in a day, but couldn't keep that up for more than a day or so. They could do 40-50 miles a day and keep that up for a week or two. The Apache warriors were known for their endurance. There are documented runs by Apache warriors of 13 hours at 9 miles an hour. That's more than 120 miles a day.

ET phone home...

[Anonymous Coward]

How about we just call the aliens and ask them to come pick us up? I saw ET do that shit in the 80's with a circular saw and some damn string.

Re:ET phone home...

[jgagnon]

http://en.wikipedia.org/wiki/File:TI_SpeakSpell_no_shadow.jpg

Our world

[Krneki]

Why do we need to go away when we still have to colonize about 80% of our planet?

The fantasy to live on another planet is irrational.

Re:Our world

[bluefoxlucid]

This is a huge fantasy. The planet is 4 times the mass of earth; so because of its gravity, I'd weigh 600 pounds. Most of the fat bitches at Wal-Mart would weigh about half as much as my car, and they'd all outweigh a 1000CC motorcycle.

Re:Our world

[prakslash]

Why do we need to go away when we still have to colonize about 80% of our planet?

Answer: Click here

Re:Our world

[nschubach]

Why do we need to go to America when we still have to colonize about 80% of Europe?

Humanity explores that which seems unattainable. It's human nature.

Re:Our world

[Anonymous Coward]

Wait, are you saying this wonderful planet will murder any fat bitch that dares to tread on it? Sign me up!

Re:Our world

[Anonymous Coward]

Why do we need to go away when we still have to colonize about 80% of our planet?

Republicans, Tea Party Activists...etc

Re:Our world

[Zenaku]

The planet is 4 times the mass of earth; so because of its gravity, I'd weigh 600 pounds

You are probably just trolling and I'm falling for it by correcting you, but just in case you actually think this. . .

No. Four times the mass does not imply that you would weigh 4 times as much unless the planet's radius is the same as the earth's. That is quite unlikely. A planet with 4 times as much mass as the earth is almost certainly going to be proportionally larger in volume as well. Gravity is proportional to mass, but inversely proportional to the square of the distance from the center of that mass. In the end, if the planet is made of the same sort of rocky material, it will have a similar density, and thus similar gravity.

Would it be exactly 1G? Probably not. Without knowing the planet's volume, we can't know exactly. But a number between .8G and 1.2G is much more likely than 4G.

Of course, I'm assuming that you weigh 150 pounds here on Earth. If you currently weigh 500 pounds, then I apologize. . . your estimated weight on this new world may have been fairly accurate after all. :)

Re:Our world

[Kozar_The_Malignant]

...so because of its gravity, ...Most of the fat bitches at Wal-Mart would weigh about half as much as my car

They already do here. No need for space travel; or have you not been to Wal-Mart lately?

Re:Our world

[nschubach]

Are you suggesting sending all Wal-Mart stores to this planet? I guess that's one way to deal with them. ;)

Re:Our world

[Anonymous Coward]

I'm in Sicily. I had McDonalds yesterday. We have colonized Europe.

Re:Our world

[Anonymous Coward]

This is a huge fantasy. The planet is 4 times the mass of earth; so because of its gravity, I'd weigh 600 pounds. Most of the fat bitches at Wal-Mart would weigh about half as much as my car, and they'd all outweigh a 1000CC motorcycle.

Incorrect...and disturbingly misogynistic.

At any rate, the radius of the planet is estimated to be up to twice the Earth's radius, and what we care about is little g = GM/r^2. Best case scenario? The mass is four times the Earth's, the radius is twice the Earth's, and your weight would be exactly the same.

Re:Our world

[Anonymous Coward]

Obviously you don't completely understand about gravity. If that planet and earth were both point sources of gravity, it would have four times the Earth's surface gravity (which would also be a lot higher). Since they aren't point sources, then the mass of the planet is at varying distances from you and therefore doesn't all pull you as strongly towards it. Most of the estimates I've seen agree on about 1.4 times the gravity of earth. Might be uncomfortable and annoying to get used to, but not crushing, and certainly survivable.

Re:Our world

[FrangoAssado]

You're forgetting that the volume is proportional to the cube of the radius, while gravity is proportional to the inverse square of the radius. So, while gravity doesn't increase linearly with mass, it's not constant either:

4x mass -> 4x volume -> 4^(1/3)x radius -> 4/4^(2/3)x gravity

So, gravity would be increased about 1.6 times. You should apologize to him if he weighs 380 pounds, not 500. :)

Re:Our world

[jgagnon]

For the oil, of course! :p

Re:Our world

[Zenaku]

No, I didn't forget that in principal, though it is true that I didn't recall the exact ratio.

You will note that I did not present any numbers about what the radius or volume would be, I only said that they would likely be proportionally bigger. I didn't specify what that proportion would be, because I couldn't remember and didn't want to take the time to look it up and show exact math, nor did I want to complicate my point by introducing an assumption of constant density.

I then estimated that .8G to 1.2G would be a more likely range than 4G, which it is. I probably should have said .8G to 2G. You are completely correct to say that 1.6 would be the exact value if the density remained constant, but I was only out to illustrate the fallacy that 4x mass -> 4x gravity.

Thank you for backing it up with more concrete values.

Re:Our world

[Anonymous Coward]

Well, assuming similar densities, a planet with 4x the mass of earth would have a radius about 59% bigger than ours ( 4 ^ (1/3)). With mass going up proportional to radius^3, and gravity going down by 1/radius^2, you're looking at an increase in weight that's the same as the change in radius (4 ^ (1/3)).

If you weigh 150 pounds here on earth, your weight on the new world would be 238 pounds. Likewise, 180 lbs becomes 285, and 212 lbs becomes 336.

Re:Our world

[Anonymous Coward]

Here's the bad news. The weight of the planet is proportional to the volume, which is proportional to the cube of the radius. While gravity is proportional to the square of the radius. So if you multiply our own planets radius by 1.59 its weight will go up by a factor of 4 while gravity goes down by a factor of 2.5 and you still end up weighing 1.6 times what you do now.

Re:Our world

[Tablizer]

Many researchers suspect its density would be higher than Earth's due to the higher gravity. It would be "compacted" more. Thus, one would be close to all the mass, and thus gravity would be pretty strong.

Re:Our world

[robi5]

Wrong. You forget the effect of planet rotation speed. So maybe he can be 400lbs or more.

Re:Our world

[blind biker]

No. Four times the mass does not imply that you would weigh 4 times as much unless the planet's radius is the same as the earth's. That is quite unlikely. A planet with 4 times as much mass as the earth is almost certainly going to be proportionally larger in volume as well. Gravity is proportional to mass, but inversely proportional to the square of the distance from the center of that mass. In the end, if the planet is made of the same sort of rocky material, it will have a similar density, and thus similar gravity.

Actually, you're wrong, as well. If we assume a similar composition, and a 4 times larger mass to imply a 4 times larger volume, the radius will be cubic square of 4 times larger, that is 1.587.
Considering that gravity follows the inverse square law, and because of a curious mathematical identity, where 4/(4^(1/3))^2=4^(1/3)=1.587, it turns out that the gravity would be 4^(1/3) = 1.587 times greater. Your numbers were way off.

This is rather elementary, if you care to turn your gray matter on instead of criticizing other people. Who may have been wrong, but so were you.

Re:Our world

[geekoid]

Because the time it takes to build and go elsewhere. If you wait until we habitat every sqr inch, it's too late. Plus a destination drive innovation. Everything you would need to do to accomplish that task could also be used to better the planet.

The fantasy to progress on ward is what makes us..well.. us.

Re:Our world

[geekoid]

wow, what a great thread. I wish we had more.
I mean.... *points* NERDZZZZZZZ~

Re:Our world

[Anonymous Coward]

Um, the effect of which is nothing.

Re:Our world

[Zenaku]

Your math is correct, and I do not dispute it. As I replied here : http://slashdot.org/comments.pl?sid=1809212&cid=33798980, I was not assuming anything about the planet's volume except that it would certainly not be the same as earth's. Hence, my very deliberate avoidance of giving a value for the planet's volume or radius, and my use of words like "similar" and ranges that would be "more likely" than others instead of words like "equal to."

I was "wrong" only in that I elected not to present a complete and concrete example with an assumed value for each variable, as that was not my goal. I only meant to point out why the naive belief that mass is linearly proportional to surface gravity (a belief that I've seen rampant in every news sites comments on this story) is incorrect.

What with this being slashdot, I should have realized that not giving a complete mathematical description of a specific possibility would lead to some asshole assuming I don't know shit. My bad.

Re:Our world

[rwwyatt]

I'd weigh 600 pounds.

Isn't that the minimum weight limit for posting on /. anyway?

Re:Our world

[Anonymous Coward]

That would make an excellent high school physics test question.

Re:Our world

[Anonymous Coward]

People in US are training to carry this much "over"weight already.

Re:Our world

[squizzar]

I'm trying to work out if you are falling down the 'there is no centrifugal force' trap or if you are merely implying it is insignificant.

My maths says that a 250kg mass man, at sea level, on the equator, will require a centripetal force of: 250*(6378*10^3) * (7.27 × 10-5)^2 = 8.4N. Presumably at the North pole this is zero. That's 8.4/2452.5 N = 0.3% (using g = 9.8, which is a bit of a circular reference here...). Not a great deal, but not nothing. Note that the force is proportional to the square of the angular velocity so if the planet was spinning 17.82x faster you would have trouble standing on the equator...

Re:Our world

[bluefoxlucid]

+1 this is excellent. I however suspect the gravity of a solid mass may lens, or something, I don't know. Why is it the tide is high on the side of the earth opposite the moon, where the moon's gravity pushes?

Mirror for the train wreck video?

[Anonymous Coward]

The video review of HP's train wreck is gone. Anyone got a mirror?

Re:Mirror for the train wreck video?

[Anonymous Coward]

Ooops, never mind. Wrong Forum. Weird.

Re:Mirror for the train wreck video?

[burisch_research]

"Deleted by poster". Damn annoying. But then again this is the wrong thread.

What I find exciting..

[rotide]

What I find exciting is the prospect of a lot of young minds trying to figure out how to get a probe there with the capability of communicating back (within a reasonable time frame) what it finds. And then the science, if it is a habitable planet, of trying to visit it.

We need a new catalyst to spark imagination and an intense drive to succeed in the sciences.

Even if it is impossible to venture there, the discoveries and new technologies that we _do_ develop that doesn't quite reach the goal, but is above anything we currently have... Exciting!

Re:What I find exciting..

[chemicaldave]

What I find exciting is the prospect of a lot of young minds trying to figure out how to get a probe there with the capability of communicating back (within a reasonable time frame) what it finds. And then the science, if it is a habitable planet, of trying to visit it.

We need a new catalyst to spark imagination and an intense drive to succeed in the sciences.

Even if it is impossible to venture there, the discoveries and new technologies that we _do_ develop that doesn't quite reach the goal, but is above anything we currently have... Exciting!

Give me funding to go to grad school and (more importantly) grants to pay me for this kind of research and I'll gladly quit my well paying salaried+benefits day job to go pursue my childhood dreams.

Re:What I find exciting..

[Anonymous Coward]

Stop encouraging them!

1040 years

[UncleWilly]

I bet in the next 1000 years humans could figure out how to make the trip at half the speed of light (40 years).

One word...

[Anonymous Coward]

...Pandorum

How about some past technology?

[Wonko the Sane]

Everyone is forgetting about Project Orion.

The biggest design above is the "super" Orion design; at 8 million tons, it could easily be a city.[6] In interviews, the designers contemplated the large ship as a possible interstellar ark. This extreme design could be built with materials and techniques that could be obtained in 1958 or were anticipated to be available shortly after. The practical upper limit is likely to be higher with modern materials.

...

Later studies indicate that the top cruise velocity that can theoretically be achieved by a thermonuclear Orion starship is about 8% to 10% of the speed of light (0.08-0.1c).[1] An atomic (fission) Orion can achieve perhaps 3%-5% of the speed of light. A nuclear pulse drive starship powered by matter-antimatter pulse units would be theoretically capable of obtaining a velocity between 50% to 80% of the speed of light.

At 0.1c, Orion thermonuclear starships would require a flight time of at least 44 years to reach Alpha Centauri, not counting time needed to reach that speed (about 36 days at constant acceleration of 1g or 9.8 m/s2). At 0.1c, an Orion starship would require 100 years to travel 10 light years. The late astronomer Carl Sagan suggested that this would be an excellent use for current stockpiles of nuclear weapons.[10]

Re:How about some past technology?

[Tablizer]

I'd like to see the Orion study shown scaled back for delivering a fly-by probe. However, traveling at 10% the speed of light means that it only gets roughly a half-minute to scan the target planet. That may be enough to give us a general overview, though. Slowing down to orbit would would be more expensive. Slowing down in space is just as hard as going fast (assuming staying intact is a requirement).

Re:How about some past technology?

[Anonymous Coward]

The biggest design above is the "super" Orion design; at 8 million tons, it could easily be a city.[6] In interviews, the designers contemplated the large ship as a possible interstellar ark.

Or...

This is what Destiny intended from the moment it entered the star system... Destiny is powered by the stars themselves...

Re:How about some past technology?

[GrumblyStuff]

8 million tons? You'd only need 6400 Saturn V to get all the components into orbit for construction. Ooof.

Re:How about some past technology?

[deoxyribonucleose]

8 million tons? You'd only need 6400 Saturn V to get all the components into orbit for construction. Ooof.

Oh, no: you build it on the ground, then launch it from a country (or continent!) you don't particularly like...

Re:How about some past technology?

[Anonymous Coward]

Also, all those time estimates are from the perspective of people on earth. If we're sending a probe, that's a fine way to measure it, but if we're sending people, they'll see the trip pass more quickly. So 100 years at 0.5c would only be 86 years for the passengers... and the faster you go, the better your odds of making it there in a crewman's (if not an observer's) lifetime.

Re:How about some past technology?

[Anonymous Coward]

RTFA. The Super Orion would be built and launched from earth. Fallout would be negligible.

Re:How about some past technology?

[butalearner]

Project Orion actually calls for the use of nukes at launch, too...on the order of 1000 of them just to get to LEO. So yeah, controlling all of those explosions is pretty highly suspect, considering all we've done is prove that graphite-covered steel spheres can survive a nuclear blast.

A far better plan is colonizing our own Solar System. Perhaps there is an asteroid or moon with sufficient natural resources that it would be better to build and launch the Super Orion from there. Of course, by that time some other technology may render the plan obsolete, but the journey would be worth it.

Re:How about some past technology?

[Wonko the Sane]

An Orion craft is still the best way to get massive amounts of equipment out of the earth's gravity well even if you are staying in the solar system.

Imagine building your entire lunar or martian base on earth and then launching it in one piece to its destination. That would be a much easier way to bootstrap a colony.

Re:How about some past technology?

[AlexiaDeath]

You don't. You need only a fraction of that to get the space plants and mining stations built, supplied and manned. After that, nothing but people and information is shuttled. The rest is built in space. This needs to happen anyway, if we are to venture off from this planet. We need to live off the space. Tap into its energy and material resources and recycle and synthesize what space does not offer.

Hmm...

[rakuen]

Sounds like I'll need more than a good book for this trip...

Re:Hmm...

[Anonymous Coward]

Sounds like I'll need more than a good book for this trip...

It's a Bring-Your-Own-Author type of trip

Re:Hmm...

[mcgrew]

Well, the Encyclopedia Galactica would probably suffice. If you can't afford a copy, the HHGTG should do.

Re:Laughable

[Anonymous Coward]

And you Space Nutters are against life extension research too...

We aren't, QA. We're hedging our bets. Have you considered that unless you want immortality to be restricted to people with the wealth of Bill Gates, we'll pretty much have to develop a means to get off this rock pretty much the day we develop clinical immortality? The oceans are big, but we went from a billion people to 6 billion people within a century or two without immortality. The oceans just aren't big enough to support a civilization of a trillion immortals.

Meantime, while someone else works on life extension, we're workin' on making sure there is somewhere to go. Easiest way to do that is have a bunch of frozen cells in the core of a space probe, and lob the probe towards the nearest suitable star, and let the robots wake the cells up in 10-20K years. A ship full of algae could go first, and a ship full of human embryos - woken and taught by robots - could show up a few centuries later.

We space nutters would also prefer if we get to see the rocks, but in lieu of that we'll settle for a scenario in which someone gets to see the rocks. If, as the Fermi Paradox suggests, we're the first sentient species capable of spaceflight, the galaxy is ours for the taking.

Nuclear propulsion.

[MaWeiTao]

For now a matter-antimatter drive might as well be a pipe dream. We don't have a way to create antimatter in any meaningful quantity. Using the current process it would take 2 billion years to produce 1 gram of anti-hydrogen. Then there's storage. Anti-hydrogen has been kept from destroying itself for 10 seconds. (Thanks, Wikipedia.)

Before we start even talking about getting to other planets there are a few things we need to do. We need a space station far more robust than the ISS. One that allows manufacturing in space. Heavy-lift vehicles get all the materials we need into orbit. It's all assembled and launched from space. Needless to say, that's far easier said than done. But if we want to engage in real space exploration I think to start outside of Earth's gravity well. Too much energy is wasted just getting spacecraft into space and building them to survive launch and flight through the atmosphere. Although, I suppose even in space they have to withstand similar loads. But the point is that if you start in space you have many more options.

And I think it's high time we restarted research into nuclear propulsion.

Re:Nuclear propulsion.

[chainsaw1]

The reason we don't have a lot of production is no one has put together a system dedicated to making antimatter. The last major hurdle was slowing down the antiprotons from a particle accelerator so they can be captured, and that was on /. a week or two ago, IIRC. All major accelerators are designed for new and varying particle studies. I would expect a purpose built device for making a specific type of particle would improve generation several times to several orders of magnitude.

As of this point, it stops being science and starts being engineering. Technology maturity, usability designs, and finally production and storage considerations.

Re:Nuclear propulsion.

[Anonymous Coward]

Wouldn't it be much easier to produce antimatter in space compared to production planetside? My guess is gravity is insignificant there and magnetic fields could compensate drift so it would not bump into the walls of it's vacuum container. And there's a lot of solar energy in space to use for production, the only problem is collecting enough of it. Maybe we could use an orbital ring covered with solar panels to get collect vast amounts of sunlight, maybe coupled with an orbital elevator for easy transport of materials from down below.

Re:Nuclear propulsion.

[Anonymous Coward]

For now a matter-antimatter drive might as well be a pipe dream. We don't have a way to create antimatter in any meaningful quantity. Using the current process it would take 2 billion years to produce 1 gram of anti-hydrogen. Then there's storage. Anti-hydrogen has been kept from destroying itself for 10 seconds. (Thanks, Wikipedia.)

Before we start even talking about getting to other planets there are a few things we need to do. We need a space station far more robust than the ISS. One that allows manufacturing in space. Heavy-lift vehicles get all the materials we need into orbit. It's all assembled and launched from space. Needless to say, that's far easier said than done. But if we want to engage in real space exploration I think to start outside of Earth's gravity well. Too much energy is wasted just getting spacecraft into space and building them to survive launch and flight through the atmosphere. Although, I suppose even in space they have to withstand similar loads. But the point is that if you start in space you have many more options.

And I think it's high time we restarted research into nuclear propulsion.

Isn't nuclear propulsion outlawed by some archaic law that says we can't detonate nuclear explosions in space?

Re:Nuclear propulsion.

[natehoy]

Heavy-lift vehicles get all the materials we need into orbit.

Or locate our manufacturing stations closer to sources of raw materials that are not encumbered by a huge gravity well. The Moon would be a decent candidate, at 1/6 Earth gravity and very close by. The asteroids would be even better, assuming we can find a couple of them with enough useful materials to justify building a station there.

Instead of focusing on reusable rockets, we need to figure out what to do with the materials we've just spent massive amounts of energy getting out of the gravity well. Having them coast back into the gravity well for reuse seems amazingly wasteful. We're not exactly short on metal here on Earth to the point where something the size of a few dozen Shuttles would make the difference between luxury and the collapse of Humanity. Send simple, non-reusable ships up there and leave them there as raw materials, then bring their occupants back in smaller, lighter capsules. Then the brains at NASA can start planning how to assemble those pieces into a mobile manufacturing facility that we can launch at the asteroid belt so it can start building colonization craft.

Re:Nuclear propulsion.

[Anonymous Coward]

Call me a troll if you want, but the USA has spent (or committed to spend) $1,000 to 3,000 billion dollars on its most recent wars (depending on who you ask).

The total, 30-year cost estimates for the ISS range from 35 billion to 160 billion dollars. Think of the space station you could build with 6x to 85x the budget (worst-best case based on those estimates).

Re:Nuclear propulsion.

[Anonymous Coward]

Give the current worldly affairs a little more time to develope and they'll soon send us hurdling out of the solar system and we'll never even have to leave the planet.. Or at least a good chunk of it.

Re:Nuclear propulsion.

[Phroon]

Using the current process it would take 2 billion years to produce 1 gram of anti-hydrogen

We are much better at making anti-protons. Fermilab's Antiproton source can regularly do 25*10^10 antiprotons an hour, with rates topping out at 28*10^10 per hour (sustained).

So you could probably manage one gram in 'only' 250 million years with what we have built today. However, the best antiproton storage machine has only held 540*10^10 antiprotons at the same time, so there'd need to be an improvement in storage.

Re:Nuclear propulsion.

[Phroon]

The reason we don't have a lot of production is no one has put together a system dedicated to making antimatter.

But we do, the Fermilab Antiproton Source. By my calculations, it currently has about an order of magnitude higher production rate than the parent's prediction (which originally comes from an un-sourced section of the wikipedia article on antimatter).

communicate time - not travel time

[Anonymous Coward]

I'm more interested in the time it takes to communicate. 20 yrs at the speed of light. That's doable. Granted we'll have changing administrations and changing agendas over that length of time, and we'd probably alternatively send messages of peace and war every 20 yrs, but at least we could have a few hundred yr communication. Would be nice to know we're not alone in the world, even if its nothing more than that.

Re:Laughable

[Anonymous Coward]

I would like to volunteer my ex-wife for service aboard one of your algae-ships.

I never said it would be soon

[dreamchaser]

I understand it quite well, and I'm humble enough in my understanding to acknowledge that if we survive another 1000 years we might solve said problem.

Re:I never said it would be soon

[commodore64_love]

And maybe we won't. Ever wonder why we've never visited by aliens? (And I mean an actual visit, with hand-shaking or gun-shooting, not some drunken redneck staring at weather balloons or lights.)

Maybe it's because the gap across stars is too large to cross, and there's simply no science to bridge the distance. Take Star Trek for example. Completely unrealistic. That one scientist says, "...develop a matter-antimatter drive, and can figure out how to bring along 530 times as much mass in fuel as is contained in the ship and cargo itself." Clearly the enterprise doesn't carry around a fuel tank 500 times itself in size. Instead they run on magic (the fuel never runs out).

Maybe there is NO science that would allow humans/aliens to cross interstellar space within said species existence. Maybe they're quite literally trapped.

Re:I never said it would be soon

[dreamchaser]

I don't disagree. I did use the word 'might'. Never have I said it's a done deal.

Re:I never said it would be soon

[dave420]

One civilisation has to be first. Just because it's not been done before doesn't mean it's impossible.

Re:I never said it would be soon

[0xdeadbeef]

I understand it quite well, and I'm humble enough in my understanding to acknowledge that if we survive another 1000 years we might solve said problem.

What an odd way of saying "my ignorance allows for a greater degree of wishful thinking".

Re:I never said it would be soon

[huckamania]

There is no gap between stars. By the time you get close to exiting our solar system, you will already be closer to a neighboring star then you will be to Sol.

The idea that we will build a ship to go to another star on a direct route is a child's fantasy, much like terraforming Mars. We need to figure out how to live in space. Once we have figured that out, we can go anywhere or nowhere. The resources in space that are close to the Earth dwarf the resources that exist on this planet.

What we need to be working on is automated fabricators and such. Propulsion is over-rated. Just start seeding the path with resources from our automated fabs and then when we do want to go somewhere, we can take our time and not have to bring everything with us.

Gene Roddenberry had it right. We need a wagon train to the stars.

Re:I never said it would be soon

[TheRaven64]

Clearly the enterprise doesn't carry around a fuel tank 500 times itself in size. Instead they run on magic (the fuel never runs out).

Note that Star Trek differentiates between conventional and magic drives. When the physicist talks about an 'antimatter drive', he is talking about a reaction drive. We can already create antimatter in particle accelerators (although the energy required makes it impractical to generate the amounts required), and his drive works basically like Project Orion - blow stuff up behind the ship to push it along. The magic drive in Star Trek does some magic space-time-folding so that distances become shorter - the Enterprise could not travel between two nearby stars with the sublight engines, and especially not with the thrusters (which are reaction drives). Even fiction has some limitations...

Re:I never said it would be soon

[D Ninja]

Take Star Trek for example. Completely unrealistic.

Seriously. Now, if you'll excuse me, I have a call on my cell phone that I have to take.

The difference between unrealistic and not currently obtainable is very slight...

Maybe there is NO science that would allow humans/aliens to cross interstellar space within said species existence. Maybe they're quite literally trapped.

In all seriousness, that's an interesting point you bring up. It had honestly never occurred to me that we (or some alien) may just be stuck on the planet they we/they are on without any option of leaving. Hm.

Re:I never said it would be soon

[Anonymous Coward]

The more you learn, the less you know.

You think you know what the world will be like in a thousand years? You know now what mankind will know then based on - what? The things you know now? What a bunch of bullshit.

Re:I never said it would be soon

[astar]

I liked your take on the gap to the stars. The usual argument goes more along the lines if we get to the next star system and colonize, then make some reasonable assumptions on how easy is would be to recurse and maybe we own the galaxy in 10meg years.

As far as space vs planet, your point has virtue for those who are silly, but you know darn well that we will do both. Who leaves habitat unused? Even the Sahara, which is really sort of an example of the failure so far of whatever ,life oriented deity you like, gets some life and includes humans. To me, it seems quite reasonable to "terraform" local deserts, so why not local planets?

Here is a sort of terraforming project that has been kicking around since the middle of last century. No interesting tech requirements, just no willpower So. as part of it, you need some new science work, but not new hardware tech. Like most things, getting the concepts right is the hard part.

http://www.larouchepac.com/node/15992

Re:I never said it would be soon

[ElectricTurtle]

What a poverty of imagination. Space travel (of terrestrial origin) has been around roughly 2 millionths of a percent of the time there has been life on earth. It's a matter of apes or angels. Extraterrestrial life is probably either pre-sentient or so far beyond humanity that it doesn't care about us any more than we care about the drama of warring ant colonies. You're acting like some iron age dipshit who just saw somebody try to fly with wings made of wax and concludes dismissively that men will just never fly. After all, nobody has flown to us, therefore it must be impossible! It can't possibly be because we simply don't know how yet, no sir.

Re:I never said it would be soon

[entrigant]

As opposed to the arrogance of assuming our current understanding of the physical world is absolute in its correctness? He was saying he's wise enough to realize we probably do not understand everything, and it is impossible to know what we've yet to learn.

Re:I never said it would be soon

[Nick Ives]

There is no gap between stars. By the time you get close to exiting our solar system, you will already be closer to a neighboring star then you will be to Sol.

Er, what?

Proxima Centauri is about 4ly away which is still thousands of years travel time with our current tech, and our solar system doesn't have a radius of 2ly.

Re:I never said it would be soon

[0xdeadbeef]

Ah, arrogance, always the first accusation leveled against scientific incredulity by the crackpot or woo-addled moron.

Don't worry, I'm sure if you wish hard enough you conjure an FTL reactionless drive that contradicts both Newton and Einstein. And we'll see who's laughing then!

Re:I never said it would be soon

[Gilmoure]

Or internet relays. I doubt we'll visit other stars as humans but some kind of ai/uploaded human consciousness might make it there.

Re:I never said it would be soon

[insufflate10mg]

It's the fact that you even included the word "might" that made him respond to you; it's very probable that there is no "might," and it is simply too difficult for the laws of physics.

Re:I never said it would be soon

[speroni]

And maybe we won't. Ever wonder why we've never visited by aliens? (And I mean an actual visit, with hand-shaking or gun-shooting, not some drunken redneck staring at weather balloons or lights.)

Maybe it's because the gap across stars is too large to cross, and there's simply no science to bridge the distance.

In a finite universe somebody has to be first.

Clearly the enterprise doesn't carry around a fuel tank 500 times itself in size. Instead they run on magic (the fuel never runs out).

Sweet dilithuim magic. They never do seem to run out even though they're always ejecting the cores at enemies

Re:I never said it would be soon

[Ol Biscuitbarrel]

Sounds like a job for Astrochicken.

Re:I never said it would be soon

[Anonymous Coward]

I'm sorry dude, but you're just an angry doofus.

Re:I never said it would be soon

[lennier]

There is no gap between stars. By the time you get close to exiting our solar system, you will already be closer to a neighboring star then you will be to Sol.

So you don't consider the termination shock of the heliosphere to be 'exiting our solar system' then?

Re:I never said it would be soon

[Nazlfrag]

From a man wiser than you: "The only thing I know is that I know nothing".

Re:I never said it would be soon

[NeMon'ess]

Perhaps the poster was confusing the size of the theorized Oort cloud? There may be specks and pebbles of matter orbiting the sun from as far away as a light year.

Re:I never said it would be soon

[robertinventor]

Why the hurry? If we learn to live in the Oort cloud, probably with fusion reactors for miniature suns, then humans will spread through the oort cloud and then reach other stars - the Ooort Cloud does spread a long way from the sun, and mingles with the comet clouds of other stars as stars pass each other in the galaxy. In not that long time geologically we will colonise the entire galaxy.

Seems almost inevitable that will happen if our technology continues to evolve, fusion is hard to do but only on timescale of decades, we are so close to it that it will surely happen quite soon on timescale of centuries. With fusion suns life in the Oort cloud could be very pleasant, probably in spinning space habitats to simulate gravity

One wonders what could stop this in fact. Once a few comets in the Oort cloud are colonised, hard to think of anything that could stop the process. And is it right for humans to colonise the galaxy? Why have no other alien species done the same and reached us already in the history of the galaxy?

Re:I never said it would be soon

[macson_g]

That's the spirit, boy!

Re:I never said it would be soon

[Profane MuthaFucka]

I don't think you understand quite what humble means.

Extrapolating the progress of physics in the last century or two to the next thousand years makes an enormous number of assumptions without evidence.

No matter how comforting this blind view of continued progress in Physics is, it's not humble to be arguing for it here. Who the fuck are you to be making guesses and to expect others to respect your unsupported guesses?

If you want a religion, don't turn physics into one. Until then, if you've got something to argue, don't fucking come here and announce your faith that it's just gonna happen. You've got to give a reason based on something other than your nebulous "understanding."

Re:I never said it would be soon

[commodore64_love]

So if I throw myself against this wall enough times, do you think I'll eventually learn to walk through it?

No. More likely the laws of physics say it's impossible. Or at least highly improbable (if I lived a million years, and threw myself against the wall constantly, there's a 1 in googleplex chance I'll pass through the wall). The same is true about crossing the space between stars.

Re:I never said it would be soon

[commodore64_love]

>>>By the time you get close to exiting our solar system, you will already be closer to a neighboring star then you will be to Sol.

Completely false. The edge of the system, the Oort Cloud, is only 0.8 lightyear away. The nearest star is still 3+ lightyears past that point.

Re:I never said it would be soon

[operagost]

The "magic" is called "subspace", where the speed of light is faster. Without knowing the nature of this subspace, we don't know how this would affect the energy required.

Re:I never said it would be soon

[TyrainDreams]

People will never fly...

Re:I never said it would be soon

[huckamania]

I'm talking more about gravitational pull. The farther away from our sun, the less tug of gravity, the closer to the next star, the more tug of gravity. Most of the closest stars are multiple systems, so I assume that you don't have to get as close to feel the effects. You could probably argue that traversing the shock wave at the edge of our solar system would be exiting our system, but it is a moot point.

Being able to live in space is the key, moving outward and onward would be a natural result.

What about a couple decades from now?

[MoanNGroan]

Considering where we were a hundred years ago, it seems rather pedantic and just as dismissive for professor grumpy pants to say it's would to take us 180K years to get there. The stuff that will get us there quickly might still be sitting on grease boards, but chances are it really isn't that far off that a robotic mission will be able to reach a system this close and do it within a reasonable timeframe (i.e. decades). Liftoff before the turn of the century, I'd expect.

What's more likely to stall this is dollars and ability for a project of this scope to survive multiple successive administrations across multiple international boundaries. And a good reason too, hopefully better than "all hands, abandon ship".

Re:What about a couple decades from now?

[burisch_research]

Uhh... which part of 20 light years away do you not understand?

If there's intelligent life...

[chemicaldave]

...to be found near us, wouldn't "they" have identified Earth as a potential harborer of life and a) attempted communication, b) sent robots, or c) tried to visit? Any meaningful discussion on getting to this place is useless without the technology to actually get there.

Re:If there's intelligent life...

[mdm-adph]

They're all too busy watching "Gliesian Shore" to care.

morons

[duck_run]

why do we a shit about another planet when we can't even control the shit that happens on our own come on people.....

Re:morons

[Anonymous Coward]

when we can't even control the shit that happens on our own

From where did you receive the notion that everything on our planet must be subject to `control'? Show me the source of that and I'll show you a genuine moron.

Re:morons

[jgagnon]

Maybe everyone is just trying to get away from YOU? :p

Damn!

[wjousts]

There goes next years vacation plans.

Overly pedantic

[dreamchaser]

A man on a good horse can maybe cover 30 miles a day unless he wants to kill the horse. A man on foot maybe 20 if he's in top shape. My comment stands. Maybe I should have said "A dozen or few" but still, you're just being pedantic.

Re:Overly pedantic

[zcomuto]

Bullshit. I'm not exactly the peak of physical fitness, (Yes, I have man tits) yet I managed to walk 15-20 miles a day - with a 15KG rucksack on my bag - for a month. There are people in he world far, far fitter than me that I'm sure could walk a lot more in a day.

Re:Overly pedantic

[Facegarden]

A man on a good horse can maybe cover 30 miles a day unless he wants to kill the horse. A man on foot maybe 20 if he's in top shape. My comment stands. Maybe I should have said "A dozen or few" but still, you're just being pedantic.

My 60 year old stepmom can go 100 miles a day on a bike over paved roads. And used to be able to do 200 when she was younger. Horses only go 30? I feel like it would be more! Don't know for sure though.

Re:Overly pedantic

[TheClarkster]

Trust a slashdot reader to miss the entire point and squabble over an irrelevant number.

Re:Overly pedantic

[zcomuto]

The point still stands that when man invented the horse, walking became easier.

Re:Overly pedantic

[SQLGuru]

http://www.columbusnavigation.com/ships.shtml

90 to 100 miles per day of travel back in 1492. And that was the typical range with 200 being not impossible.

Re:Overly pedantic

[dreamchaser]

And you can do that carrying all the gear and supplies you'd need for a potentially multi-week journey? I don't think so. Of course terrain matters. In the mountains I cover about a dozen miles a day when I go on extended trips. In more flat situations it's probably double that.

Re:Overly pedantic

[jgagnon]

Man invented the horse?

Re:Overly pedantic

[rubycodez]

100 miles in 24 hours can be done, there are marathons in europe for it

Re:Overly pedantic

[zcomuto]

well, It's not like they dug a horse out the ground one day. That's just stupid.

Re:Overly pedantic

[davegravy]

(he means Researched the Horseback Riding technology after Animal Husbandry)

Re:Overly pedantic

[mcgrew]

A horse travelling 15 mph with 15 minute breaks every hour could travel 100 miles in less than a day -- do the math. A man on a bicycle could do it.

Re:Overly pedantic

[nbauman]

My 60 year old stepmom can go 100 miles a day on a bike over paved roads. And used to be able to do 200 when she was younger.

Yeah, but bicycles were invented in the 19th century.

Re:Overly pedantic

[catbertscousin]

I was going to, but I needed Bronze Working first.

Re:Overly pedantic

[Facegarden]

My 60 year old stepmom can go 100 miles a day on a bike over paved roads. And used to be able to do 200 when she was younger.

Yeah, but bicycles were invented in the 19th century.

Yeah. I was more wondering about the 30 miles on a horse thing. Is that really all? I'm just curious.

Re:Overly pedantic

[TheRaven64]

Man invented the bit (the thing that goes in a horse's mouth, connected to the reins), which was the technology that allows horses to be tamed and used for transport. This was invented approximately 5,000 years ago and set the maximum speed for humans to around twenty miles per hour (with short bursts up to 50) for almost all of the intervening time. The development of the steam locomotive, around 200 years ago, increased this speed to around 100 miles per hour. After that, the internal combustion engine and the jet made the leap to a few thousand miles per hour in under half a century. Solar sails and nuclear-powered ion drives push this maximum up even further. The rate of change of maximum speed for a human has been increasing a lot over the last few centuries.

Re:Overly pedantic

[GooberToo]

I think its funny how many people don't really understand what they are talking about.

Pragmatically, further back that a couple hundred years ago, people rarely traveled. Period. It was largely the aristocracy and wealthy and/or merchants who did the vast majority of traveling. A minority traveled father than twenty to forty miles; and that was typically a city trip for supplies. Its not like in the movies where everyone is constantly traveling around. Traveling to a new area frequently means months to years to become re-established. Its a big, life changing event.

Some exceptions are the military. On foot, on clear terrain, forty to fifty miles were expected. They could do more but would generally be useless for fighting if they did. On horse, with good terrain, calvary would expected to do roughly eighty miles. On rough terrain, a foot soldier was expected to do twenty miles. In heavy forest and/or mountains, snow, etc., ten miles is a good day. Now keep in mind, these guys had heavy equipment they had to carry too, not to mention supplies. And that's really the magic of it all. Having water and food is key. Sure, you *can* travel a much father distance, but being absolutely useless for the next couple of days, assuming you don't die, assuming supplies can catch up, doesn't do anyone any good whatsoever. And don't forget, most places didn't even have roads outside a city. That's one of the things that made Rome great after all.

There are some noteworthy exceptions, such as some of the African tribes who are legendary at running vast distances (example, Zulu) and going right into combat - and winning. But these guys carried only a shield, spear, and absolutely minimum of food and water, and even then, it was war. It was not an everyday event.

Going back to antiquities, it was exceedingly rare to ever travel outside of your valley - again, unless you were a merchant. Realistically, people did not travel. When they did travel, they rarely traveled father than twenty to thirty miles. Those that did travel farther than that, typically had a vocation which required it (merchant, navy, explorer) or a wallet to simply allow for it (summer, winter home). And even then, when they did travel, it was exceedingly rare to be great distances in a day. And of these, ships are the sole exception - until trains - and then cars and planes.

Re:Overly pedantic

[Anonymous Coward]

Lets think about it. If you slept 8 hours a day and devoted the other 16 to travel, you would need to average less than 2 mph to cover 30 miles. I'm pretty sure a reasonably fit human could do that. With sore feet, perhaps, but without even approaching exhaustion.

A horse could go much further.

Re:Overly pedantic

[thethibs]

"Assume a spherical horse" is not an effective approach in this case.

People who care about their horses will ride them no more than 40 miles in a day--this is the "Boston Marathon" equivalent, with time off afterward. Endurance races can be longer, but they kill or cripple a lot of horses.

Pony Express stations were 10 miles apart--that's as far as good horse in good condition can go at a gallop.

A bicycle is faster and more efficient than an ordinary horse (racing horses are faster, but they don't go very far). Sometimes technology wins.

Re:Overly pedantic

[Anonymous Coward]

A man on a good horse can maybe cover 30 miles a day unless he wants to kill the horse.

They used to change horses at stations and did much better that 30 miles a day with mail-coaches, etc.

Re:Overly pedantic

[Anonymous Coward]

Bullshit. I'm not exactly the peak of physical fitness, (Yes, I have man tits)

I modded you informative but maybe you were a bit too informative. People don't want to know that you have man tits. Shoehornjob

Re:Overly pedantic

[Anonymous Coward]

That horse must be pretty shitty to only get 30 miles.

Actually a man in shape can cover 50-60, and a good horse a bit more.

Your "maybe 20" comment comes either from ignorance or playing too much Oregon Trail, because yes: covered wagons only covered 10-20 miles in a day. But you're talking about:
-a house on wheels
-pulled by farm horses or oxen not meant to provide tranportation
-loaded down with (literally) TONS of supplies
-traveling across open country (wheels minus road = extremely slow)

Or you're talking about the stereotyped computer nerd who huffs and puffs after climbing a flight of stairs.
But you severely under estimate the travel capacity of man.

Re:Overly pedantic

[Cajun Hell]

Tell me more about this "the wheel."

Re:Overly pedantic

[Anonymous Coward]

I also didn't want to know that you carried a "15KG rucksack on [your] bag." TMI

Re:Overly pedantic

[NEDHead]

Does the road to the stars have bikeways?

Re:Overly pedantic

[Anonymous Coward]

Actually, a man on foot can cover double that in 10 hours.
I did on the Keswick to Barrow 40 mile march in the north of England 2 years ago.
Hell, my boss even did it in 4 1/2 hours. Over rough terrain, seemingly endless hills.

And I had 30kgs of gear on my back ;)

Re:Overly pedantic

[Facegarden]

Does the road to the stars have bikeways?

Yes.

Re:Overly pedantic

[geekoid]

Did you walk, or did you march?
A few hundred years ago, very few people would walk 20 miles, and most couldn't unless they happened to have a proper diet.

Eat 1000 calories a day and try it.

Re:Overly pedantic

[jonbryce]

You could travel much further in a boat. People in Europe managed to get across the Atlantic and colonise new territory for example.

Re:Overly pedantic

[PmanAce]

I have walked 43 km in one day before with about 22 pounds of weight in a pack-sack. This was after having walked for about 17 days straight. I am sure I could do 60 km without those 2 impedements since I have done 24 km in 4 hours once. 6 km/hr can be done.

Re:Overly pedantic

[Anonymous Coward]

This is the first comment I've ever seen that deserved a +10, funny. Good job!

Re:Overly pedantic

[SETIGuy]

Yeah, 30 is about right for a light rider with minimal additional load for one day. You could probably average 20 a day in that condition. Add a wagon and 10-15 might be the maximum. Visit any rural area and the distance between towns is probably dependent upon how far you could travel in a day when they were established. 10 miles or less apart when the dominant mode of transportation was walking. 15 to 20 miles when horses or horse+cart became dominant. After all, if you're building a home on the frontier, you probably don't want it to be more than a day's ride from town.

Re:Overly pedantic

[HawaiianToast]

It's just an excuse to talk about his tits.

Re:Overly pedantic

[Zerth]

The pony express only averaged 10 mph and they switched horses once an hour.

If you didn't mind killing a champion racehorse, you could ride 3 days straight and get about 350 miles before it dies. That's only like 5-7 mph. Sprint racehorses can do 26 miles in an hour, but then they're exhausted. A quarterhorse can up to 50 mph, but they only have to run for 20 seconds.

Horses are good at carrying lots of stuff and running quickly for short distances. A human is good at walking for days and days, but with substantially less gear.

Re:Overly pedantic

[NitroWolf]

Bullshit.

I'm not exactly the peak of physical fitness, (Yes, I have man tits) yet I managed to walk 15-20 miles a day - with a 15KG rucksack on my bag - for a month.

There are people in he world far, far fitter than me that I'm sure could walk a lot more in a day.

Having been someone who has actually done something like this, I can assure you that you did not walk 15 - 20 miles a day with a 15Kg ruck and you are not in top physical condition. You might be able to do it for one or two, possibly three days, but after the 4th day you would be quite literally physically unable to move. This does not even take into account the condition your feet would be in by the fourth or fifth day, to say nothing of the 21st day.

I'm sorry, but your statement is just so absurd to anyone who's done any sort of long distance walking with a heavy pack as to be completely laughable. You may have been high on what ever hallucinogenic drug you chose to take for that month and THOUGHT you did that, but you most certainly did not walk even 15 miles a day for a month, especially not with 30+ pounds on your back.

Re:Overly pedantic

[mdielmann]

A man on foot maybe 20 if he's in top shape.

I disagree entirely. An average person walks at about 4 miles per hour. Right now, you're saying that unless you're in good health, you can't do that for 5 hours a day.
A top athlete just ran 26 miles in 2 hours in the Toronto marathon. People in lesser shape than him routinely do it in less than a day. That's >20% over your rough estimate.
Fully equipped Roman soldiers were expected to march 25 miles a day in full kit (about 50 pounds). This included camping at night and all the other good things soldiers on the move have to do (like being in good enough condition to fight if attacked), as well as the drawback of having to maintain unit integrity, which slows a person down. Scouts moved faster. I would certainly agree that they count as being in top shape, but not necessarily top athletes. Yet they do far more than you expect someone in top shape to do, with equipment about 2000 years out of date.
A good tracker can run down a person on horseback, and that is why. It may take a few days, but it can be done. Horses aren't meant for that kind of work, day in and day out - people are. The fact that the average person can't is an indicator of how much people, including myself, under-utilize their bodies.

Re:Overly pedantic

[yurtinus]

According to the wikipedias, endurance horseback races can be up to 100 miles per day - but that is for only the tip top competitors on a single day trip (with regular supply intervals). Riding for multiple days carrying all the gear? 30 miles a day would probably be pretty optimistic on *good* roads. Kudos to your stepmom - a century is a tough ride (and two is ridiculous!!), but could she cover 100 miles a day, every day for a week, while carrying all of the food for the trip *and* a day or three worth of water? How about on a dirt road or trail? Hopefully you're seeing that it's not entirely fair to compare the range of a horse on a trail with that of a human with a machine on a good road.

If you need to cover a lot of ground and don't have a good machine *and* good roads to do it, you have to expect it to go pretty slow.

Re:Overly pedantic

[turbidostato]

"A man on foot maybe 20 [miles a day] if he's in top shape."

Quite a bit more. Unless Wikipedia is wrong Yiannis Kouros, from Greece, owns since 1997 the world record for a 24-hour run a bit over 20 miles: 188,590 miles to be precise.

20 miles a day, every day, can be acomplished by "normal" people since that's a typical daily stage for Way of St. James pilgrims (about 200.000 of them this year).

Re:Overly pedantic

[dakameleon]

... so one might say human acceleration is accelerating?

*ducks*

Re:Overly pedantic

[Kryptonian Jor-El]

I call bullshit. Doc Brown had one hell of a time getting the train up to 88 for the DeLorean to travel from 1885 to 1985

Re:Overly pedantic

[Anonymous Coward]

When I talk on the phone to random customer support I often ask where they are, and they are usually in the Philippines. Then I say that I have a friend who lives there, and in the ensuing conversation it turns out that people who answer phones in the Philippines have never travelled anyplace, not even in the Philippines.

Re:Overly pedantic

[Anonymous Coward]

Ok let's think about it. You forgot to factor in all of the supplies that you would need to do this as well as breaks for eating(including cooking) and other things. Its also unlikely that you'd devote an entire 16 hours to travel, even if you didn't have to deal with food. Walking for 16 hours while carrying a bunch of shit is not as easy as you're making it out to be.

Re:Overly pedantic

[Anonymous Coward]

The numbers for the humans aren't in line with what we're capable of.

http://en.wikipedia.org/wiki/24-hour_run gives that the longest a human has run in a day is 303.5 km (188.5 miles). Would be in the category "killing himself".

A human in top shape can sustain 28 miles per day for 22 months straight ( example: http://en.wikipedia.org/wiki/Jesper_Olsen_(runner) ).

Re:Overly pedantic

[Anonymous Coward]

However real horses can't gallop all the time like they do in a Hollywood movie.

Re:Overly pedantic

[GooberToo]

I mean all roads lead there which was a pretty big advantage, I think.

Exactly. Rome was the first country/empire to officially recognize roads as a military and economic weapon. They built roads throughout their entire empire for exactly those reasons.

Even in the US, rail and roadways were officially funded by the military. In fact, even to this day, a huge number of signs have DoD information on the back for military use in the event of catastrophic emergencies. Countries without highways can not properly defend themselves.

Re:Overly pedantic

[Zerth]

Either you are from one of those countries that uses a comma as a decimal mark but still uses imperial measurements, or Yiannis Kouros reached orbit.

7857 mph average speed is rather impressive for a human.

Re:Overly pedantic

[operagost]

The ability to coast on a bike, thus preserving momentum, is huge.

Re:Overly pedantic

[Anonymous Coward]

Are you kidding? Marathon runners routinely cover 25 miles in less than 2 and a half hours. Ultrarunners (men in top shape) do 50 miles or more. I'd say a good equestrian should be able to ride twice as far in a day.

So back to the topic, Gliese 581g is only 117,569,580,721 years away on horseback. Just make sure those interstellar drive-ins have enough hay...

Re:Overly pedantic

[CmdrGravy]

You seriously took 30Kg of gear for a one day hike ? WTF for you masochist.

But, do they have oil?

[l0ungeb0y]

If so, the US will be more than happy to inva^H^H^H, bring democracy and free trade to it's inhabitants

Re:But, do they have oil?

[Anonymous Coward]

It could be worse: They could all be sitting around complaining how nobody wants to clean out the sewers or work harder then their neighbor because they don't get any benefit to doing it. Then of course they will blame their king for not giving them more reward for their labors. Maybe the king just needs to enslave this other group of people to make them clean our sewers...

At first thought...

[lymond01]

When I first read this, and someone saying it would take 180,000 years to travel there, I thought, "Maybe we can bring that planet to us!"

But then the various issues with this, not least of which that location matters when discussing habitability, struck me and I thought, "Okay, that wouldn't work."

Even if you made a spaceship sized tunnel between here and there, essentially pulling some section of their solar system across the light years to meet with a section of ours...a wormhole if you will...

Re:At first thought...

[nschubach]

Even if you made a spaceship sized tunnel between here and there, essentially pulling some section of their solar system across the light years to meet with a section of ours...

I can't be the only one who imagined a long straw... with a wet paper spaceship.

Heim Theory?

[TheNarrator]

Just had to mention Heim Theory here:

http://en.wikipedia.org/wiki/Heim_Theory

Extended Heim theory (EHT) is being researched as a possible way to utilize non-propellant methods of interstellar travel, specifically in overcoming the massive distances involved in any space journey. [39]
[39]http://www.hpcc-space.de/publications/documents/AIAA2010-021-NFF-1.pdf

Response #1

[Anonymous Coward]

The first response to the discovermagazine.com story reads:

Well what pi$$es me off is that people have this idea in their heads that they even have the RIGHT to go and colonize this new planet. Why do we just automatically assume that it’s ours for the taking if we so desire? Why? Just because we found it sitting there that makes it ours to exploit?

This is a theoretical discussion about an undertaking that can't even be realistically considered for the foreseeable future, yet even discussing it is some moral crime worthy of public derision. You really must admire the left in its success at inculcating such a depth of self loathing into the western world. Even inconsequential, totally blue-sky matters must be coerced into the self-hating anti-human mindset, and anyone foolish enough to do otherwise may be cursed without restraint.

Welcomed there by ... their great^N-grandchildren!

[dazedNconfuzed]

Current space-travel technology, even accounting for an Orion ship powered by every nuke on Earth, would take so long to get there as to receive a warm welcome by the travelers' own great^N-grandchildren, whose ancestors stayed behind long enough to develop Dilithium Crystals, Warp Drives, and/or whatever technology will whisk travelers there on the order of a few hours.

Bill Bryson's take ...

[WankersRevenge]

If you haven't read A Short History of Nearly Everything by Bill Bryson, do yourself a favor and pick it up. It's wonderful read about pretty much everything. He opens with a chapter on space travel which he says, ...

The point to remember, of course, is that when considering the universe at large we don't actually know what is in our own solar system.

Now the other thing you will notice as we speed past Pluto is that we are speeding past Pluto. If you check your itinerary, you will see that this is a trip to the edge of the solar system, and I'm afraid we're not there yet. Pluto may be the last object marked on schoolroom charts, but the system doesn't end there. In fact, it isn't even close to ending there. We won't get to the solar system's edge until we have passed through the Oort cloud, a vast celestial realm of drifting comets, and we won't reach the Oort cloud for another - I'm sorry about this - ten thousand years. Far from marking the outer edge of the solar system, as those schoolroom maps so cavalierly imply, Pluto is barely one-fifty-thousandth of the way.

Of course, we have no prospect of such a journey. A trip of 240,000 mils to the moon still represents a very big undertaking for us. A manned mission to Mars, called for by the first President Bush in a moment of passing giddiness was quietly dropped when someone worked out that it could cost $450 billion and probably result in the deaths of all the crew (their DNA torn to tatters by high-energy solar particles from which they could not be shielded).

Based on what we know now and can reasonably imagine, there is absoulutely no prospect that any human being will ever visit the edge of our own solar system - ever. It is just too far. As it is, even with the Hubble telescope, we can't see even into the Oort cloud, so we don't actually know that it is there. Its existence is probable but entirely hypothetical.

Re:Bill Bryson's take ...

[cjonslashdot]

I remember leafing through the book "The Science of Star Trek", and thinking that the author simply did not have much imagination. For example, the author assumed that a "transporter" would have to "scan" all of one's atoms, in the way that a fax machine scans a piece of paper. Yet, if teleportation is possible, it probably does not involve scanning: it probably involves some kind of quantum entanglement mechanism - and even that assumption is based on the very limited understanding that we have today of how things work and what the universe is made of.

The fact is, the universe's fabric is so bizarre that we probably cannot imagine how a future race might be able to travel near the speed of light, or at it - or perhaps even beyond it. Going from one place to another might not even involve "travel" as we think of it.

So to dismiss anything at this point is pointless.

However, the point about the vastness of the solar system - and the space between solar systems at that - is very well taken. It is beyond comprehension.

Perhaps when it becomes possible to traverse these distances in some manner, humans will no longer exist in their current form; perhaps we will have long since merged with machines and become something so different from what we are today that we cannot even imagine it.

Re:Bill Bryson's take ...

[maugle]

"Based on what we know now and can reasonably imagine, there is absoulutely no prospect that any human being will ever visit the edge of our own solar system - ever. It is just too far."
... that sounds a bit like:
"Man will never reach the moon, regardless of all future scientific advances."


Humanity is funny that way. Give us a goal and a guy telling us it's impossible, and we'll figure out a way to do it.

Re:Bill Bryson's take ...

[misexistentialist]

One good thing about that perspective is that exploring the hottest woman you have seen recently seems almost too easy. Better choose two.

Re:Bill Bryson's take ...

[Anonymous Coward]

Imo, the transporter should involve some wormhole type mechanism, because that makes it easier to explain how you do it with only one transporter, not two.

What About In Our Own Backyard?

[BJ_Covert_Action]

Sure, chucking a probe 20 lightyears away would be awesome, and if we could scrape together the international will and resources necessary to do that I would be all for such an effort. But what about exploring some of the more exciting areas in our own celestial backyard, if you will?

To date we have only had landers on a few of our planets. We only have functioning rovers on one. We had an impact probe on only one of the moons circling the gas giants. We have rendezvoused with one asteroid, and we have gotten two probes into the Kuiper belt. So, before we go dumping trillions of dollars (and it will cost at least that much) into a tiny (and it will be tiny) scientific payload to another solar system, can we start funding some serious exploration here first?

I want to see landers, rovers, and submersibles on Europa, Enceladus, Titan, Ganymede, Io, and Callisto. I want to see regular sample return missions to near Earth asteroids. I want to start a ferry program between LEO and the Earth's surface for more than a handful of elite astronauts. I want to see experimental habitats on the moon, rovers on Venus, probes on Mercury, orbiters around Jupiter, Saturn, Neptune, Uranus, and even Pluto, and I want to have at least ten more robots actively exploring Mars. Don't get me wrong, Gliese 158g is one hell of an interesting planet and we should study it as best as we can with out long range sensors and, as one 'dotter even suggested, perhaps we should try communicating with it. I see no reason to evens start thinking about sending a matter-based payload to that planet, however, until we really take some time and effort to start exploring our own solar system. For as much as we have done here, we still really don't know all that much about our home system. I, for one, am not convinced that there are not colonies of methane-based life on Titan and a whole city of icy fish people swimming under the crust of Europa. Let's not even start talking about the possible cloud people of Venus or the cave-dwellers of Mars...

Re:What About In Our Own Backyard?

[Anonymous Coward]

I can put something in Uranus really quick.

Re:What About In Our Own Backyard?

[Anonymous Coward]

It just seems ludicrous to send zillions of our planet's resources out into space on a mission that will never come to any possible fruition. We need those resources here on this planet.

Re:What About In Our Own Backyard?

[butalearner]

I'm with you on most of that, but unfortunately with limited budget we need some priority. Colonizing our Solar System, to me, should be our top priority, so we should focus on the places where we stand the best chance of building permanent habitats in a relatively short time. The moon, obviously, plus Mars, asteroids including especially Ceres and Vesta, Jupiter's Galilean moons (though probably not Io), and Titan for its nitrogen-rich atmosphere. It will be very interesting when our Dawn spacecraft reaches Vesta in the next couple years and Ceres a few years later.

Mercury and Venus, unfortunately, are much, much further away from that goal. If only Mercury were tidally locked with the Sun, we might colonize the band where the temperatures are reasonably comfortable. It'd be interesting to send a flyer to Venus, but we simply couldn't survive the atmosphere right now. Orbiters around the gas giants themselves aren't going to help us as much as orbiters that are free to explore their moons. Pluto has New Horizons speeding towards it, so we'll get to find out what interesting properties it has, but we'll likely have something similar much closer to us.

3 Millions years?!

[Silpher]

From TFA: "3 million years to collect on earth if the entire surface were covered with solar panels" We NEED a frickin Dyson sphere NOW! GODAMMIT!

not worth it until travel is faster/safer

[bl8n8r]

A lot can change on a planet in 180,000 years. In only 100 or so, we've pretty well toasted this one. Besides, putting all the money, effort and resources into a trip which will take that long just isn't worth the risk vs. cost. There is too much we don't know about the universe to embark on something like that with our current knowledge level.

Re:not worth it until travel is faster/safer

[MetalliQaZ]

That's why the first interstellar travel should be undertaken by our (robotic) representatives... possibly carrying human DNA.

Re:not worth it until travel is faster/safer

[phyrexianshaw.ca]

there you go, thinking like a business-person.

the risk vs cost of doing anything shouldn't influence one's decision making. you only live once: maybe for once you do something with your life that DOESN'T look good on paper.

what's the worst thing that can happen? everything changes forever? that's going to happen anyways.

Go visit a children's cancer ward.

[apparently]

And go tell said children that curing cancer isn't "forward thinking" enough. I'm curious to see what kind of response you'd get.

Re:Go visit a children's cancer ward.

[vistapwns]

Sure, after you tell them that 10 more years of life IF that is better than indefinite life spans, end of poverty, crime and all diseases.

Re:Go visit a children's cancer ward.

[amRadioHed]

Wow, when you put it that way it's so obvious.

And hey, come to think of it what am I doing spending my money on rent and food when I could be buying lottery tickets? Obviously winning a hundred million dollars and retiring to my own private island is way better then just eating and staying warm.

Yeaaaah ......

[unity100]

That other planet had just called me, and it told me it cant wait for this civilization going there and shitting, polluting and ravaging itself too. it just cant wait !!

Re:Yeaaaah ......

[equex]

Nice, tell them they will only get 50% of the shit! If that is too bad for them, we can just find two new planets when we get there, then we have 4 planets to each give our 25% shit to! Actually, when colonizing truly starts, there's probably enough planets available that we each can have our own private planet. There's probably even enough empty galaxies for each and every one of us to own.

Re:Yeaaaah ......

[JSBiff]

"The Planet" doesn't care whether we shit or pollute. Animals of one kind or another have been shitting all over the earth for what, a Billion years? Shit's just part of the planet. So is "Pollution". "The Planet" doesn't care about mercury, lead, sulfer dioxide, oil, or anything else - it's all part of the planet and has been part of the planet for Billions (or hundreds of millions, in the case of oil) years. "The Planet" doesn't care about Global Warming, Ozone Depletion, or anything else.

It is *we* who need to worry about our shit and pollution. It is we who will suffer (and other organic life) from pollutants, or from radioactive contamination or whatever. As far as "The Planet" is concerned, everything is "natural". Lead is natural, uranium is natural, oil is natural.

Re:Yeaaaah ......

[unity100]

so then ?

Re:Yeaaaah ......

[Anonymous Coward]

so then we need to stop phrasing environmentalism as "saving the planet" and start phrasing it in terms of "don't shit where you eat".

Re:Yeaaaah ......

[unity100]

difference ?

Re:Yeaaaah ......

[Anonymous Coward]

So tell the planet to shut up!

Re:Laughable

[CRCulver]

We aren't, QA. We're hedging our bets. Have you considered that unless you want immortality to be restricted to people with the wealth of Bill Gates, we'll pretty much have to develop a means to get off this rock pretty much the day we develop clinical immortality?

Woven into the plot of Kim Stanley Robinson's trilogy beginning with Red Mars is a pretty good argument that, even with multiple space elevators running nonstop, it might not be feasible to move enough people off the Earth to offset increased longetivity and high birthrates.

Learn to walk first

[petes_PoV]

From what we *know* this planet is more Mars-like than Earth-like. So if we were going to go anywhere in the hope of either finding life or of settling, ourselves forget travelling 20 ly, just try travelling a few hundred million km to our nearest neighbour and finding life there. Once we can do that then there is a point to dreaming about going further out.

As it is, even if we set off to the Gliese 581 system today, when we finally got there we would undoubtedly find life - ourselves. As Larry Niven points out in his fiction, by the time our current technology takes to get there, someone will have invented / discovered a faster way of travelling and will therefore overtake our 21st century probe en route.

Re:In a word: NO.

[NCG_Mike]

Develop it? Can't we just use the Stargate under NORAD?

What about a boat?

[nbauman]

How fast was a boat a few hundred years ago?

Magellan's expedition went around the globe in 3 years.

Mars

[ballwall]

Isn't mars in our 'goldilocks zone'? But because it doesn't have a magnetosphere it can't sustain an atmosphere against solar winds? (Not sure, just something I remember reading about). If so, how do we know the odds of habitability of planets in the zone? Couldn't it be that, yes, they do need to be in that zone to support life, but only 1% of planets in that zone have other factors that contribute to that support? (Like a magnetosphere)

Re:Mars

[phyrexianshaw.ca]

Sure, the chances of life existing when conditions are prefect are infinitely small: but the universe is nearly endless. the odds may be stacked against such a planet from being so near to us, but there's nothing preventing it from happening!

Re:Mars

[Anonymous Coward]

Isn't mars in our 'goldilocks zone'?

The wikipedia has a pretty good spin on the goldilocks zone (aka Habitable zone)

The habitable zone is not to be confused with the planetary habitability. While planetary habitability deals solely with the planetary conditions required to maintain carbon-based life, the habitable zone deals with the stellar conditions required to maintain carbon-based life, and these two factors are not meant to be interchanged.

Apparently, mars is just outside our current understanding of a 'goldilocks zone'...
http://en.wikipedia.org/wiki/File:Habitable_zone-en.svg

But as we find more extremeophiles in our own biosphere, the definition of the goldilocks zone gets larger...

(posting anon to avoid any karma dings for quoting the wikipedia to people too lazy to read it)..

Can we travel to it...

[meerling]

After all, it's only and astronimical hop, skip, and a jump away at only 20 light years. Of course that's the equivalent of telling a 4 year old in London that they can have all the free ice cream they want in New York City if they just walk/swim there. For an adult, it's not a trival thing to do, but still possible, and in the analogy, our race and society are still wearing metaphorical diapers.

We currently don't have the technology or resources to pull off a 20 light year trip, even if it's one way.

And if we did, what would we find when we get there? A planet with higher gravity, and otherwise a completely unknown environment. It may have no water, atmosphere, oxygen, or something else we desperately need to live. On the off chance it has an ecosystem, is it one that is even compatible with us, or would we have to totally destroy it before we could supplant it with our own? What if it has intelligent life? No matter how you look at it, colonizing that place would be a tricky proposition, assuming we were even able to get there in the first place.

Just a note, we currently don't have any form of life support systems that can sustain human life for 6 years without getting occasional fresh supplies, something which can't happen on an interstellar voyage. So even if you could travel at 92% light speed, you'd still die before you got there. I love sci-fi, but I also know a bit about the reality of our current developmental situation. We have a long ways to go before we can explore the stars.

A new energy source

[Anonymous Coward]

I think traveling to this planet, as well as numerous other possible advances, are dependent on developing a new source of energy. Not that we're at the limits of what we can do with our current sources of energy, but we're closing in. And interstellar travel is going to require a source of energy that can last a long time and put out a lot of power to keep a ship accelerating to make the trip in any reasonable amount of time.

Oh wait, you're right

[nbauman]

My mistake.

Circumference of the earth = 24,000 miles / 3 years = 1,095 days

= 22 miles/day

Re:Oh wait, you're right

[jschen]

Magellan didn't just go along the equator, plowing his way through landmasses. The actual distance he travelled is significantly longer than the circumference of the earth. So his average distance covered per day is longer, too.

Re:Oh wait, you're right

[nbauman]

Oh, well. Within an order of magnitude.

Enrico Fermi told me to just make a reasonable guess. http://en.wikipedia.org/wiki/Fermi_problem

creation of antimatter

[rubycodez]

I used to work at a place that made antimatter (Fermilab, and it was anti-hydrogen ions to be precise). the creation of antimatter is incredibly energy intensive and inefficient- to produce one gram would cost $100 quadrillion. The idea of making ten thousand metric tons or so of the stuff is ludicrous. we might make antimatter bombs someday, but not starship engines.

Re:creation of antimatter

[cowdung]

I used to work at a place that made antimatter (Fermilab, and it was anti-hydrogen ions to be precise). the creation of antimatter is incredibly energy intensive and inefficient- to produce one gram would cost $100 quadrillion. The idea of making ten thousand metric tons or so of the stuff is ludicrous. we might make antimatter bombs someday, but not starship engines.

Umm... maybe we'd have to invest on making better production techniques first?

Re:creation of antimatter

[phyrexianshaw.ca]

yeah because when we talk about potentially moving our civilization out into space, expanding the limits of humanity, and divulging on the largest and single most galaxy changing event in the all the history that we know about:

the first thing everyone thinks about is how much it'll cost.

Re:creation of antimatter

[rubycodez]

even if we went to a wealth-less society, "high cost" in this context means antimatter is extremely rare in this universe and very unlikely to form from energetic collisions. The surface of earth couldn't contain enough particle accelerators to make a meaningful amount of antimatter for star travel. For that matter, black holes above subatomic size but small enough to emit massive amounts of energy, also potentially useful for star travel, have the same issue of "cost".

Re:creation of antimatter

[rubycodez]

there is only one way of making the stuff in our matter-dominated universe, energetic collisions. the yield rate is very very low. So we can either do the collisions ourselves (CERN can make 1 gram of antimatter in about 2 billion years), or scoop up natural sources (such as val allen belts) which also are very very sparse. Neither way would get us the HUNDREDS of TONS needed for space travel, just a wee fraction of a gram for years of effort.

The type of black hole that emits a huge amount of radiation also has the same production issues as antimatter.

So fusion is more likely, and we might get up to 6% of C with that. at least that's not hopeless, getting to nearby stars in decades isn't such a bad deal.

Hardly.

[Anonymous Coward]

My comment stands.

No it doesn't. Of course, only a pedant would spend more time pointing out all the inaccuracies .

fusion a more realistic option

[rubycodez]

a fusion starship might approach 0.3 % of the speed of light, taking decades to go to the near stars. That would be taking 100x the mass of the cargo as deuterium or boron fuel.

see my other post on why antimatter won't be used for starship fuel, just too damn expensive and energy intensive to make.

Re:fusion a more realistic option

[NewWorldDan]

[citation needed]

That's what I love about these threads. Everyone spouting off about whether a fusion or anti-matter spaceship would be better, despite the fact that neither exist. We haven't even gotten to the mean free path of space and how much damage a speck of dust would cause to the hull at 0.0001C. The one thing we all seem to agree on is that we're not getting there any time soon. Baby steps, people. Shouldn't we be sending a probe of some sort to Proxima Centauri first?

Re:fusion a more realistic option

[rubycodez]

your shielding problem has already been solved, couple centimeters of titanium for up to 0.3C, tens of feet of water for up to 0.8C. As to engine, fusion bombs exist. project orion type craft would use fusion bombs and an ablative shield. the physics are quite straight-forward, and by launching from space rather than ground the radiation fallout would be non-issue.

considering the trillions of dollars wasted in recent years on our fake wars, bailouts, monetary system pumping, imagine what could have been done.

Just ask Congress ...

[PolygamousRanchKid]

... they can't even agree on what they want NASA to do in our own little space area. Traveling to Gliese 581g will depend on the current party holding office, and whether Gliese 581g constituents make it a "Red" or a "Blue" planet.

So the question will not be about technology, but politics.

Re:Just ask Congress ...

[JustOK]

or porn. Imagine the first real alien porn.

I agree

[Colourspace]

It's nicely re-assuring to think we might not be a fluke in a planetary sense, at least not in our 'neighbourhood'. But surely terraforming has to be the realistic way forwards?

180,000 years!

[jplopez]

Well, six months before the Wright brothers flew for the first time, they said that heavier-than-air flight wouldn't be possible for at least another 1,000 years...

Build a Bigger Telescope

[MichaelCrawford]

It would be easier to build a telescope that could resolve the surface of the planet, than it would be to travel there.

Fuel?

[sqlrob]

Why is fuel a problem? Wasn't that solved with ramjets?

Now shielding to block the radiation from that is another problem entirely.

Re:Fuel?

[WhiteDragon]

Why is fuel a problem? Wasn't that solved with ramjets?

Now shielding to block the radiation from that is another problem entirely.

I was thinking exactly the same thing. I wonder why there's not more discussion on Bussard ramjets.

A Signal was heard...

[Anonymous Coward]

Well sort of - still kind of interesting... check out this site...
http://www.dailymail.co.uk/sciencetech/article-1316538/Gliese-581g-mystery-Scientist-spotted-mysterious-pulse-light-direction-newEarth-planet-year.html

Let's use trial-and-error to...

[Tablizer]

...send our politicians there.

Re:Laughable

[Anonymous Coward]

"We aren't, QA."

Oh YES you are, virulently so.

"Have you considered that unless you want immortality to be restricted to people with the wealth of Bill Gates, we'll pretty much have to develop a means to get off this rock "

If you have the energy and resources to launch that much stuff into space, we have the energy and resources to live here quite nicely. Have you noticed that the planet is quite sparsely populated? There is no resource problem on Earth. There is a political and greed problem on Earth. This is coded into our DNA, it won't get better when we're in free-fall (which incidentally is extremely harmful to humans... Solved that yet? With even more unattainable technology?)

"Meantime, while someone else works on life extension,"

And yet, how many fanboi, drooling and panting stories do we get on Slashdot every time some worm lives twice as long as normal? None. How many retarded stories do we get every time some nostalgic fool loads a white metal tube with kerosene to do exactly the same as before?

"We space nutters would also prefer if we get to see the rocks, "

And then what? What do you do 1 minute after the fact, and realize the rocks there are the same as here? We have lots of rocks HERE, and WE'RE in space! What if OUR rocks are some other species' unattainable goal? Then what? Isn't every rock on Earth as precious as one 250 LY away?

So pick one up, look at it, get over it, and let's cure aging!

20 Light Years Away

[orsty3001]

If we had a telescope large enough you'd see people there standing in lines to see Total Recall right now.

Re:20 Light Years Away

[Tablizer]

Wouldn't it take 20 years for the movie broadcast to get there and then 20 years for your telescope image to get back to you? We're talking 1970. Or am I over-thinking this?

Re:20 Light Years Away

[orsty3001]

Well technically it would take longer than that since the movie didn't broadcast until after it was released in 1990. But going by the assumption that Hollywood is magical and movies release everywhere within weeks of the premier, then yes we could see this happen just like I stated.

nah, send self replicating molecules

[SlideGuitar]

Whatcha wanna do here is send small self replicating molecules.... accelerate them at the speed of light toward habitable planets in some kind of accelerator gun... let them land on the distant planet and start evolving... wait a billion years or so and voila... they start sending radio signals announcing their arrival.

It will be "us", but perfectly adapted to wherever "we" land.

In fact, that may be how we got here. We may be the aliens finally reporting back to the mother planet right now.

Re:nah, send self replicating molecules

[rhyder128k]

I was thinking that sending a probe might be a better idea than sending human beings. Bare in mind that advances in nano technology and computer technology might enable the creation of an extremely small probe. If the probe was the size of a video cassette, making the fuel supply 540 times bigger might not be quite so impractical.

Re:nah, send self replicating molecules

[Anonymous Coward]

Hell, make it small enough and antimatter drives become slightly less impractical too...

As they say in the "service"...

[Anonymous Coward]

Travel the (galaxy), meet interesting natives, then kill them all.

Re:I have never understood this

[Phrogman]

Chekov supposedly has a Russian accent. However, he pronounces /v/ as if it was /w/. Russian has a /v/ and lacks a /w/. So we are basing our most famous Russian accent on someone who has a speech impediment?

Or is it just Americans who can't recognize some sounds properly (the way they think us Canucks say "oot and aboot" which we do not. Up here its "owt and abowt" if anything).

I think you are off almost a millionth...

[way2trivial]

http://www.google.com/search?sourceid=chrome&ie=UTF-8&q=world+population
world population 6,697,254,041

http://www.google.com/#hl=en&expIds=17259,23756,24472,24692,24878,24879,25566,25984,26095,26562,26714,26792,27006&sugexp=ldymls&xhr=t&q=+6697254041-++99.999999%25+of+6697254041+&cp=13&pf=p&sclient=psy&safe=off&aq=f&aqi=&aql=&oq=+6697254041-++99.999999%25+of+6697254041+&gs_rfai=&pbx=1&fp=c6affe93747c32d0

6 697 254 041 - (99.999999% of 6 697 254 041) = 66.9725409

66.97 people? I'm guessing it's more like 6,697 who give a shit-- so that would only be
99.9999

Hold on, Flatty

[Tablizer]

It's estimated to be roughly 3 times more massive than Earth. This means its gravity will be at least double ours (depending on the radius). I doubt humans can live long under such gravity. Our spines already fail at 1g. Well, maybe rolling beds? At least sex will be easier. And you don't have to get out of bed to go to work. Just wake up and drive using a horizontal monitor. Sign me up!!!!
   

Re:Hold on, Flatty

[guspasho]

Actually, because the radius is also larger the estimates are around 1.1g to 1.7g, which should be tolerable.

However, there are still a ton of things we don't know about it. Given what we know it could be a Venus-like planet.

Re:Hold on, Flatty

[Tablizer]

As I mentioned elsewhere, some models suggest it would be more dense than Earth, and thus the radius wouldn't be significantly larger. But it's all speculation at this point anyhow.

Re:Hold on, Flatty

[butalearner]

Actually, because the radius is also larger the estimates are around 1.1g to 1.7g, which should be tolerable.

Not to mention that our bodies would mostly adapt within a single generation. A child who lives their entire life subjected to higher gravity will almost certainly develop the muscle to handle it. Just look how quickly our muscles lose the ability to handle Earth gravity after a few months of weightlessness. Our other internal organs evolved in 1g, but it is reasonable to assume our increased muscle will make it tolerable even at the upper edge of predictions. It is also reasonable to assume that we will have artificial gravity for the trip, so the passengers will have had time to adjust.

Re:Overly pedantic - more like overly ignorant.

[Anonymous Coward]

20 miles on foot in top shape? Obviously you're a basement dweller. I backpack through very difficult terrain and average 15 miles a day. This is carrying a 15 - 30 pound pack depending on season and duration of the hike. I'm not a fast hiker, nor am I anywhere near "top shape". Someone in top shape through difficult terrain could do 20, 25 on the outside. On flat ground, carrying no load? More like 50.

Google Appalachian Trail runners and you'll see what a top athlete can do in a day through difficult terrain.

Too Far to Swim

[emo65170]

Does anybody else reading this discussion find new appreciation for this life raft that we all share?

The Big Question

[Anonymous Coward]

The Big Question is why would we want to go there? All of the answers have bad implications for us here on Earth especially given the improbability of us actually getting there.

NBC News's contact link

[matt_morgan]

Brian Williams said, “It’s just nice to know that if we screw this place up badly enough there is some place we can all go.” Tell NBC News how dumb and upsetting this comment is at http://www.msnbc.msn.com/id/29104230/

Lies, and not accounting for drift over time

[name_already_taken]

Or is it just Americans who can't recognize some sounds properly (the way they think us Canucks say "oot and aboot" which we do not. Up here its "owt and abowt" if anything).

When I used to live close to the Canada - US border, we used to watch CBC, and they did indeed say oot and aboot in a boot, although it may have been as a joke.

I always thought it was odd that no other Russians pronounced V as W as Chekov did. But then, Picard spoke with an English accent but was from France. Patrick Stewart said Picard was more European than French, in that Europe had become united. Perhaps a similar thing happened with Russia and whatever countries are nearby, causing their accents to change over the next couple of hundred years.

Do you think the Russian pronunciations of today are the same is it was a few hundred years ago? English certainly wasn't.

Re:Laughable

[Anonymous Coward]

"We aren't, QA."

Oh YES you are, virulently so.

Oh, wow. Now that you put it that way. I had never realized before just how much against life-extending research I was, thank you for pointing that out to me.

And yet, how many fanboi, drooling and panting stories do we get on Slashdot every time some worm lives twice as long as normal? None.

I don't really want to count, but here are a few samples. We talk about it all the time, pal.

The real problem isn't that we're against other research. The problem is that people like you have the mindset of "we need to concentrate on MY favorite topic. Everything else is a waste of time and resources!". The majority of geeks and nerds, especially the types into space research, believe we should explore everything.

Re:Laughable

[TheRaven64]

increased longetivity and high birthrates

That's the issue. I wouldn't be surprised if my generation is given this as a choice - indefinite life extension or children (possibly with the option of having your genetic material stored for IVF at some point after your death from accident or violence). Bad luck to those who already had children...

Don't forget ponies.

[apparently]

Nanorobots will give us an indefinite supply of sweet, delicious ponies.

I like your logic that curing cancer in children only gives them "10 years" of life added, instead of y'know, an actual human lifespan. Maybe one day, you'll be able able so snort a line of nanorobots, and they can relocate your logic circuits from your anus to your brain; we can only hope, right?

Re:I have never understood this

[Anonymous Coward]

You almost had it too...

Different regions of the world have different accents. Even in America in the 'south' there at least 5 different accents. Yet the one everyone calls 'southern' is an Alabama (bamma) accent.

Watch all of kids in the hall (I will wait). They have a very subtle Canadian accent (more upstate new york). However they say about as aboot once and awhile. And sorry as soory almost consistently.

The actor who played checkov was probably imitating people from his family as they were from Lithuania. http://www.imdb.com/name/nm0000479/bio

All we need to do is communicate with them

[WillAffleckUW]

If we can communicate with them, and send over our DNA sequences, then they can grow copies of humans, bring them up in their own society, and train them for the invasion force to conquer Earth.

Re:I have never understood this

[geekoid]

SInce it was a character from the 60s, we can't really expect a lot.

I really enjoyed the new movie, except for Chekov. Really, you have a computer that can understand almost every language in the universe, but it can't figure out a Russian accent?
And of course having him run to get to the station while people fall instead of transferring control to his station was also lame.

Re:I have never understood this

[ElectricTurtle]

Canada is not a monolith. There are places in Canada where people say 'aboot' and consequently all Canada is mocked through them. Just as "American" accents are mocked through those prevalent in the Deep South, or the Valley Girl "dialect", when most of the country sounds like neither. (Being from Washington State, people sometimes think *I'm* Canadian, which happens to many who live in border states, though especially to those from ND, MN, WI, MI and ME.)

P.S. People who pronounce 'both' like 'bolth' need to be slapped until they stop. There is no goddamn 'L' in that word.

They planet just called me

[geekoid]

it says it needs me to get some stones. Now a need to get a towel to wipe off my forehead.

Vasmir

[jwhitener]

I haven't seen anyone mention vasmir yet http://www.nasa.gov/vision/space/travelinginspace/future_propulsion.html

Wouldn't this be the ideal drive type to power a probe? Extremely efficient and can basically accelerate continually, then flip around and begin de-accelerating (or maneuver near other objects to let gravity slow it down). Wikipedia says that Nasa is going to test it in space in 2011 or 2012.

1G engine

[aashenfe]

Ok, if we had an engine that could produce 1G of accelleration over a large number of years.

Does anybody how long would it take to get there?

Half the trip would be accelerating, and the other half decelerating. (Actually it's accelerating the whole time, just in the opposite direction at some point.

1G of acceleration should solve the muscles atrophying problem as well.

Re:1G engine

[imnotanumber]

Ok, if we had an engine that could produce 1G of accelleration over a large number of years. Does anybody how long would it take to get there?

With constant acceleration a = 1G = 9.8m/s^2 we have v = a.t
With maximum v = C = 299792458 m/s
t = 299792458/9.8 seconds = 0.969393127 years

So 1 year to accelerate, 1 to decelerate, 19 to travel at 0G...

No muscles atrophying problem solving this way. :(

Re:1G engine

[aashenfe]

Cool,

Why the 19 years at 0 G? I know that is the speed of light, but if you are are going nearly that fast, and you measure the speed of light, in any direction, it would still be 299792458 m/s which means you can still accelerate at 1g and never reach that speed.

Then of course, we would have to have two times. One time for the astronauts on the spaceship, and another as observed from earth.

Any ideas on what those times would be?

Re:1G engine

[imnotanumber]

Cool, Why the 19 years at 0 G? I know that is the speed of light, but if you are are going nearly that fast, and you measure the speed of light, in any direction, it would still be 299792458 m/s which means you can still accelerate at 1g and never reach that speed. Then of course, we would have to have two times. One time for the astronauts on the spaceship, and another as observed from earth.

Yes there are two times, one for an observer here on earth and another to the spaceship passengers.

The times that I gave are for the observer here on earth.

Any ideas on what those times would be?

For the the spaceship passengers, the time dilation would make the voyage look shorter. At the speed of light (witch theoretically could not be reached) time would "stop" and only the acceleration and deceleration periods would be perceived.
Perhaps that's why the passenger could think that they are always accelerating... Weird... At least, the muscle atrophying problem could be solved this way.

You must be in "Marketing"

[Anonymous Coward]

You must be in "Marketing." Or believe in fantasies. Reality doesn't matter to folks like that.

The reality is without some major new physics discoveries, we will not get outside our solar system - at least not while alive. I can see where people will pay to have some ashes shot into space, but it will be 200,000 yrs just to get to our closest neighboring star (4LY away).

Reality is where engineering lives.

Sure, you can create a virtual world and call it whatever you like. That is trivial compared to this problem. It is like asking a colony of ants to build a Boeing 777 airplane - that's how hard this problem appears today.

An excellent resource

[Anonymous Coward]

This paper was proposed in 1976, but it is one of the best looks at what may be required for Interstellar travel to Alpha Centari:
http://www.askmar.com/Robert%20Bussard/Interstellar%20Exploration%20Program.pdf

Here is a more modern look at Interstellar space travel ideas: http://en.wikipedia.org/wiki/Interstellar_travel

IMO: we should not even consider discussing sending humans this far/long. Light satellite probes would be difficult enough.

Please have a look and figure out how we can harness the energy to do this. I really want to see (close photo of) an exoplanet in my life.

Somebody stop us

[supachupa]

As exciting as the idea is to me of exploring another world, I think if there are other intelligent beings out there they should stop us from leaving our world until we can learn to take care of it properly. Otherwise, we will just spread our destruction in search of profit.

We are discovering the wonders of the universe...

[mpthompson]

await, but we are trapped on our little planet. To paraphrase Admiral Kirk:

EINSTEIN!!!!

Sure we can!

[reboot246]

You can be anywhere in ten minutes if you drive fast enough.

Send them a message

[Skapare]

"All your base are belong to us".

Then in 40 years, if anyone is there, we could get an answer. "We dare you to come and get all our base".

Re:Send them a message

[thijsh]

No, in forty years you get the answer: "Somebody set up us the bomb", followed shortly thereafter by: "For great justice!".

Uplift Denied

[Databass]

Probably the best bet is to copy it from visiting aliens, if any ever bother to visit.

I was thinking about this and: we're not ready. To this day, we have people who use what little technology they do have (chemistry etc) to make bomb vests and blow themselves up. We're still an absolutely greedy, violent species who regularly wars all the time.

The mass and energy involved in interstellar travel is sufficient to destroy planets. (I always wondered why they needed the Death Star when they could just accelerate a smallish frigate into a planet at lightspeed and accomplish the same thing. Planetary shields maybe.)

Any aliens moving amongst the stars must have a code of social justice and cooperation sufficient not to destroy themselves with their own technology. That code almost certainly includes rules for not giving technology to belligerent pre-stellar species. Would YOU start handing out laser pistols to a room of tantrumy 2-year olds?

If you wait for all the lights to turn green

[symbolset]

If you wait for all the lights on your journey to turn green before you set out, you'll never leave home.

So what if it's a hundred thousand year journey? Put together a 10,000 crew mission and set them on their way. For certain the fight won't be over who has to go. It will be over who has to stay here.

Re:I have never understood this

[tverbeek]

True. As a Michigander I can confirm that Yoopers* sound more like Canadians than they sound like Trolls.* "Say yah to da UP, eh!"

*Upper Peninsula dwellers, the region of the state closest to rural Ontario
**People who live "below the [Mackinac] Bridge"

Currently impossible

[Bruha]

First you will have to break several laws of physics just to move fast enough. Your first enemy is gravity. So you plot your course and lets say hit light speed. You're now dead, the gravity well of the Sun has just squashed you like a grape only messier. Now imagine a faster than light system that's capable of detecting objects in the path and avoiding/deflecting/destroying them, it would have to be faster than you are and vastly more complex.

Better to point antennas at it, and worse if there is any advanced civilization there, they're currently still watching the cold war on TV. I'm sure they can not wait to visit, or worse they're a few years from arriving and wiping us out.

*Damn it! Where my tin foil hat!*

More important...

[SlovakWakko]

...than the fact that currently we don't have a way to get there is the fact that now we have the reason to find the way.

Many tiny probes

[Mandrel]

Yes, I think tiny self-aware probes will be the way we'll do it. A one-gram probe would still require a Hiroshima to get it to .85c.

You'd be able to launch billions of them, both to target many stars at once, and also to allow the probes to communicate down chains.

You'd be aiming to impact a planet (make it survivable by building the probe mainly out of diamond), after which the nanotech would sprout and build something better. Rather than a simple scatter-gun approach, the probe could steer as it travels by releasing radioactive decay particles left and right.

Using this you could expand the front of exploration at .8c, and pwn the galaxy in 100k years.

Major questions: how to accelerate the probes, and can a .85c impact be survived.

Over taken

[krystofa]

I've always been amused by these theoretical journeys. How annoyed would you be if you got all the latest kit together set of for a star knowing that your great-great-great-(whatever, you get the gist)-grand children will be the first people to shake hands with an alien (or get zapped by their photon gun) when all of a sudden you get over-taken by some upstart joyrider in the latest spolundigated retrocharged thunder rocket (tm) which hadn't been invented yet. Oh well, you think. They will probably get over taken too. Its the only journey that you will complete faster by sitting on you **** doing nothing.

Don't give up quite yet...

[Anonymous Coward]

In fact, the immense cost of 530 time the vessel's mass only comes from trying to accelerate to the maximum. Going with realistic speed of 0.5c allows a more realistic cost:

http://nnmusings.blogspot.com/2010/10/after-recent-discovery-of-first.html

Innovative Propulsion System

[Anonymous Coward]

Antimatter production is almost impossible with current technologies. Aneutronic nuclear fusion is more affordable. Furthermore, we need spacedrive more efficient in terms of energy usage than expelling-mass rockets.
spacedrive video

Are you SERIOUSLY this Clueless?

[Anonymous Coward]

There is no gap between stars. By the time you get close to exiting our solar system, you will already be closer to a neighboring star then you will be to Sol.

Are you SERIOUSLY this clueless about distances? The closest neighbor star is 4.2 light-years away http://www.astro.wisc.edu/~dolan/constellations/extra/nearest.html. The edge of the Sol system http://burro.astr.cwru.edu/stu/solarsystem_edge.html is approximately 17.6 billion miles (120 A.U.) away.

There are about 63115.2 AUs/lyr. That means the edge of the solar system is: 120AU/63115.2 = 0.001901 light years in distance. Oh - you bet that's closer, 0.001901 is "almost" the same as 4.2 light years.

B-58 Hustler

[Anonymous Coward]

In 1956 and supersonic nuclear bomber existed called the B-58 Hustler http://en.wikipedia.org/wiki/Convair_B-58_Hustler. It was a Mach 2.3+ aircraft according to a pilot. Since that time, no other non-black-program bomber has reached those speeds. They just point out that progress comes in spurts and can't be predicted. Over the last 40 yrs, we've become more efficient, but there haven't really be any breakthroughs in propulsion since the 1950s.

Those facts have very little to do with space craft speeds. The fastest man-made spacecraft of any kind went about 180,000 mph after all the fuel was used up. Stellar distances are huge and there are all sorts of problems. Going to the closest star (4.2 light-years away) will take 200,000+ years and that assumes fuel, oxygen, water, power can all be replenished along the way "magically" so we can slow down on the other side. Let's not forget the radiation protective systems that need to be built and all the psychological concerns of hundreds of thousands of years without significant sunlight seeing the same people over and over in a confined space.

Innovative Propulsion System

[rbrtwjohnson]

Antimatter production is almost impossible with current technologies. Aneutronic nuclear fusion is more affordable. Furthermore, we need spacedrive more efficient in terms of energy usage than expelling-mass rockets. spacedrive video

No mass required

[WindShadow]

"One scientist puts the travel time at 180,000 years based on current space flight technology, while another explains that it could be quite quick if we build a matter-antimatter drive, and can figure out how to bring along 530 times as much mass in fuel as is contained in the ship and cargo itself."

As this article explains, there's new science afoot, and propulsion need not require expulsion of mass any more. Note that energy would still be needed, and the technique needs to be engineered up from the current proof of concept stage to an actual ship, but the need for big mass may be gone.

Since the acceleration is based on mv=mv, accelerating low mass particles to very high velocity might offer a very high thrust to mass ratio. In other words that "530 times" is open to improvement if higher exhaust velocities are used.

The real limiting factor is how much acceleration the payload can take, and what your target top velocity (cruising speed) will be before braking starts, and of course available energy regardless of mass requirements. Assuming Vmax of .5c gets to the destination in a lifetime, but doesn't get data back. If entangled particles could be used to pass data, the requirements would no longer include return hardware, and results would be in quickly. Interesting speculation. Of course there are nearer systems, and while ideal planets haven't been seen, they could exist and would be currently undetectable.

Just need star gates.

[Anonymous Coward]

Not like on television. We need a pair of smaller, 1m, rings that only connect to each other. Perhaps an additional pair of 0.1m rings for refueling. The energy used to open and maintain the connection needs to be significantly less than energy from the fuel being sent. Then we put one set of rings on a unmanned, nuclear-powered ship and refuel along the way. When the probe arrives, we send people and equipment through the 1m rings.