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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."
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.
SJW: Someone who has run out of real oppression, and has to fake it.
Project Orion could get us there.
How long would it take at warp 6, Ensign Chekov?
http://alternatives.rzero.com/
Just convince some corporation that it has unobtainium.
Is it just my observation, or are there way too many stupid people in the world?
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.
Do really dense people warp space more than others?
Kids today! When I was a lad, we would've killed for a Sulfuric Acid atmosphere. We had to make our own air!
"We returned the General to El Salvador, or maybe Guatemala, it's difficult to tell from 10,000 feet"
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.
Years later, a doctor will tell me that I have an I.Q. of 48, and am what some people call "mentally retarded".
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.
Banu
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?
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).
may be there are far far away, with there babbys
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!
Everyone is forgetting about Project Orion.
...
You were lucky. We had to cobble a planet together out of dust in an protoplanetary disk!
I am officially gone from
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.
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.
I read the internet for the articles.
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.
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...
Motorcycles, Robots, Space Gossip and More!
They're all too busy watching "Gliesian Shore" to care.
It is by my will alone my thoughts acquire motion; it is by the juice of the coffee bean that the thoughts acquire speed
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. :)
If fate makes you a motorcycle, you become a motorcycle.
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".
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.
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
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.
It would be easier to build a telescope that could resolve the surface of the planet, than it would be to travel there.
Request your free CD of my piano music.
What an odd way of saying "my ignorance allows for a greater degree of wishful thinking".
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.
...send our politicians there.
Table-ized A.I.
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?
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. :)
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.
The living have better things to do than to continue hating the dead.
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
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.
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.
People in cars cause accidents....accidents in cars cause people
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.
"The agriculture ministry is not in charge of Gundam" - Japanese ministry official.
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.
If fate makes you a motorcycle, you become a motorcycle.
I wish I had mod points... parent is relatively correct..
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.
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?
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.