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3 Habitable-Zone Super-Earths Found Orbiting Nearby Star
astroengine writes "Gliese 667C is a well-studied star lying only 22 light-years from Earth in the constellation of Scorpius, but it appears to have been hiding a pretty significant secret. The star has at least six exoplanets in orbit, three of which orbit within the star's "habitable zone" — the region surrounding a star that's not too hot and not too cold for liquid water to exist on their surfaces. Astronomers already knew that Gliese 667C had three worlds in orbit, one in the star's habitable zone, but the finding of three more exoplanets, two of which are also in the habitable zone is a huge discovery. Finding one small planet in a star's habitable zone is exciting, but finding three is historic. 'The number of potentially habitable planets in our galaxy is much greater if we can expect to find several of them around each low-mass star — instead of looking at ten stars to look for a single potentially habitable planet, we now know we can look at just one star and find several of them,' said Rory Barnes, of the University of Washington, co-author of the study, in an ESO press release Tuesday (June 25)."
I'd like to get more information about these worlds before I die. Also, I'd like to know if I would really get my own planet if I went "Full Mormon" so I can prepare accordingly.
Everything is relative. 22 light years, ludicrously far away in every day terms, is a hop skip and a jump in astronomical terms.
Maybe not today. But 22 light years is pretty close in galactit terms. Even at half the speed of light you can get there in less than a lifetime. Technology tends to advance forward you know. 150 years ago the thought of getting from N.Y to London in 8 hours was the stuff of fantasy. Today its an everyday thing.
I'm still waiting for us to find the five-star system from Firefly. We could use dozens of plants and hundreds of moons to terraform.
Why so? In context of just how freakin' big a galaxy or the entire universe is, 22 light years is pretty damned close. The Milky-way alone is > 100,000 light years across.
Not even 25 years ago the prevailing belief was that there wouldn't be that many stars with planets, and now we're finding them pretty much constantly.
One of the terms of Drake's equation is how many stars have planets, and that proportion has been steadily climbing.
So if we're finding this many planets in an astronomically-relative 'nearby', then throughout the rest of the galaxy we have to assume there's just vast amounts of them. Start factoring in the sheer number of galaxies, and even if we'll never meet them, it seems probable that somewhere else would likely have evolved life by now.
Lost at C:>. Found at C.
Actually, it really does. If you're looking for a star such that a space shuttle can fly there in a week or two, I have some surprising news for you. If you're looking for a star that's conceivably reachable by a generation ship, this is it.
"nearby" is relative. At 80 miles, the beach is nearby relative to, say Germany. But I still wouldn't want to walk there.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
I think I will be avoiding the peacekeepers thanks.
Yeah, but if we send a radio message now there is a good 0.000000000000000000000000000000000000001% chance an intelligent civilization that has developed on one of those planets will get it and we will have a response 44 years later. We should therefore earmark billions of dollars for this work and get right on it!
It would take a leap in some branch of technology, true. (Perhaps several.)
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
But 22 light years is pretty close in galactit terms.
You made a huge boob in your post.
There are many exoplanet claims with both the transit method and the Doppler method. What I'd like to see is use them in the same systems to see whether they yield the same results. Right now, these are only predictions, not discoveries, and they are hard to verify.
One problem that has not be determined is how do planets deal with the inherent variability with Red Dwarf stars. There are many, many more red dwarfs than other types of stars and their expected life expectancy is longer the estimated end of the universe. But their small nature makes their energy output more variable than a star like our sun.
Does the long life, and greater number of Red Dwarfs significantly boost the drake equation? Does the variable energy output reduce the drake equation?
Unfortunately, we will all probably be long dead before we find out.
150 years ago the thought of getting from N.Y to London in 8 hours was the stuff of fantasy. Today its an everyday thing.
Yeah, but 11 years ago getting from NY to London in less than 4 hours was an everyday thing (if pricier than other flights). Now it's unheard of. The only planes in service that have the speed and range don't regularly make that kind of trip and they don't take passengers. Modern enthusiasm for advances in technology seems to be limited mostly to whatever the latest smartphone is. Also, the people clamouring for those more advanced smartphones also typically have no clue whatsoever about the actual tech specs of them and are typically just being led around by the nose by marketing. Some of us are very pessimistic about the future of real technological development, at least in the short term.
You've made a serious mathematical or other error in your calculation - wow. It's not a 0.000000000000000000000000000000000000001%, it's actually a 0.000000000000000000000000000000000001% chance!! Maybe you miscounted the number of intelligent civilizations?
"Somebody has to do something. It's just incredibly pathetic it has to be us."
--- Jerry Garcia
It took us 200 years to increase normal-ish transport speeds from 5mph to 500mph. (Though bulk transport is still more like 30mph.)
We've got a LOT of technology to develop if we want to increase normal-ish transport speeds from 500mph to 1/2 light speed.
It's just about a million times faster than current tech. Even if you assume we get 100x speedup every 200 years, that's another 600 years of tech, though of course I concede that development doesn't need to be 100x every 200 years.
Making this even worse is the fact that energy required (nonrelativistic) goes as v^2. So we need ~10^12 as much energy to move stuff at 1/2 light speed (actually worse due to the relativistic factor.)
Your confidence in technology is nice, but I for one find the numbers involved downright sobering.
--PM
There's plenty of data both pro and con about sending a probe to explore and the timeline necessary. Has anyone ever thought about seeing if perhaps another race has sent a probe at us? And if so, how would we spot it?
Here's to hot beer, cold women, and Glaswegian kisses for all.
Right now it doesn't matter if it were 1.5 light seconds away. We can't get there. It may as well be in another universe. By the time we can conveniently travel that far, the whole concept of distance will be meaningless. For the sake of argument, yes, 22 light years is closer than 13 billion, but for now, in practical terms, the distance is infinite. If you already bought your ticket, I would suggest you ask for a refund.
“He’s not deformed, he’s just drunk!”
"Even" at 0.5C? You'll need to travel closer to light speed and be able to accelerate at a pretty spanky rate to average that speed. Getting a manned ship to 0.1C with a reasonable acceleration might be hard but doable with next-century tech, but anything more is rather far fetched unless there is some fundamental breakthrough in energy generation, propulsion or physics in general (warp drives or wormholes). Hey, I'm hoping to see this happen just as much as the next guy, but it's not looking good.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
I think in the context of the Fermi Paradox finding lots of habitable planets is _bad_ news because it invites the question "so where the hell is all the intelligent life on all these habitable planets" the aswers to that question indicate a term in the drake equation is close to zero, hopefully it isn't the term that indicates the length of time a technological civilization exists....
The problem is, we don't even have space shuttles any more. We're technologically regressing as far as air and space go. Still, if we ever manage to get our act together well enough to actually build something like a generation ship, 22 light years away is pretty close, relatively speaking.
But 22 light years is pretty close in galactit terms.
You made a huge boob in your post.
A Freudian nipple-slip, I suspect.
Bullshit, you didn't even get your numbers right with that hyperbole. Orders of magnitude are tough, but not entirely unworkable.
Mars is 22 light MINUTES away, and we can get there reasonable well if we had a mind to.
If you can get up to a decent fraction of the speed of light, energetically very expensive I'll grant you, a ship could get to one of these worlds in 100 years or so. That's a long time, but it's not so long as to be considered infinite or unworkable. If you take the point of view that's it pointless to consider how far our grasp can extend, of course we'll never get there.
Right now it doesn't matter if it were 1.5 light seconds away. We can't get there. It may as well be in another universe.
1.5 light seconds is roughly the distance to the moon. If we had another Earth like planet that close (assuming a somehow stable orbit and ignoring geological and evolutionary impact) you could be vacationing there right now.
Technology has always advanced in fits and starts. That enthusiasm for a particular field has waned and our achievements in it have regressed does not mean it will not begin advancing again.
I don't know...1 light second is 186 282 miles which isn't THAT far
While seemingly true, this statement is misleading. Having found 3 habitable planets around a single star, it does not follow that all stars have 3 habitable planets. Or even that any other star has 3 habitable planets. I really hope this was just a statement made out of context...otherwise...it just makes me sad.
The point is that planets in the habitable zone are clearly not so rare (either that or we've gotten really, really lucky looking for them). I agree that it does not follow that all stars have three habitable planets. However it does make the odds vanishingly small that no other star has three habitable zone planets.
Ummm, the moon is 1.5 light seconds away, and Mars is 4 light minutes away. We can, and have, send stuff to both of those, so 1.5 light seconds isn't this intractable distance you think it is ... if you were walking it would essentially be infinitely far away. But with rockets from the 60's it was more like a few days.
I'm not suggesting we're going to reach these any time soon, but you have to remember that relative to the scales we're talking about, 22 light years in astronomical terms is a very close distance.
I haven't bought a ticket, but you need to re-think your concept of what is 'infinite' and what kind of distances are truly insurmountable.
Lost at C:>. Found at C.
Right now it doesn't matter if it were 1.5 light seconds away. We can't get there. It may as well be in another universe. By the time we can conveniently travel that far, the whole concept of distance will be meaningless. For the sake of argument, yes, 22 light years is closer than 13 billion, but for now, in practical terms, the distance is infinite. If you already bought your ticket, I would suggest you ask for a refund.
22 years means you can send a message and get a response in your lifetime.
1.5 light seconds is roughly the distance to the moon.
And when was the last time we had humans on the moon? Distance doesn't matter all that much when we don't care enough to continue exploration of what's already reachable.
But even in space "nearby" is relative. We can reach Mars in a reasonable amount of time, using technology that's the space equivalent of "walking". Reaching even the nearest star is a whole 'nother story. Something else needs to be invented in order to achieve that. Or as someone smarter than I once said:
“Space is big. You just won't believe how vastly, hugely, mind-bogglingly 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.”
(Well, who did you *think* I was going to quote??)
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
The Fermi Paradoxon is no paradoxon.
The most evil sin all over the universe is: man made self replicating machines.
No sane race ever will do that: crafting self replicating machines and letting them lose on the universe.
In the time spans we are talking about: all things you could imagine will go wrong with "replicators". You don't need to read SF to grasp that. At Fermis times no one really thought that out. So his idea is sticking Round as "paradoxon".
Would YOU with all the SFs you have seen support a "self replicating" machine being send to another star system? Just to multiply there and go on?
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
I'm not sure what difference this makes to the actual habitability of the planets, but all of these are tidally locked. That is, the same part of the planet is always facing the star (and thus baked) while the same part faces empty space (and thus freezes). A thick atmosphere might transport heat and make things more uniform, but none of these are what one would naively think of as "habitable". In fact, all planets in the "habitable" zone of such small stars are going to be tidally locked. Wikipedia actually has a nice summary of the problem of tidal locking in small stars.
On the other hand, they might have very interesting moons.
The solar system called "Sol" also has three planets in the habitable zone. Besides Earth a second one, Mars, was likely once habitable. Venus for some reason got a veyr dense very CO2 heavy atmosphere. With less CO2 it likely would harbor life.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
That's true if you think the government's "space program" is the measure of human progress. That's what you get for pinning your hopes and dreams to a bureaucracy funded by money stolen from people at gun-point.
The private space industry, on the other hand, is growing and succeeding at quite an optimistic rate, relative to what most people though was possible 10-15 years ago.
I feel like this submission title has greatly lowered the bar for "habitable."
I think in the context of the Fermi Paradox finding lots of habitable planets is _bad_ news because it invites the question "so where the hell is all the intelligent life on all these habitable planets"
Obviously you're unaware of Oliver's Solution to the Fermi Paradox: They discovered reality tv. Then civilization collapsed.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
There are no humans on the Moon because there's nothing to do on the Moon. There are only so many kilos of regloith you can ferry back and rounds of low gravity golf you can play before there's no point spending the billions to go back. If and when someone thinks up a useful reason to go back to the moon (e.g., a way station for missions to further afield) then I'm sure we'll be back.
If the Moon were an Earth-like world, I'm sure there would be a McDonalds serving Moon Burgers up there by now.
We're finding enough potentially habitable exoplanets that it's worth sending messages to them. Some might have a civilization. It's time for SETI to start transmitting.
This is quite possible. Arecebo could communicate with a similar installation across the galaxy.
PKD beat you to that...the 1953 short-story Imposter, and the 2001 movie of the same name! They where from Alpha Centauri, but still...
The 'insurmountable' doesn't exist. The impractical is a little different. And to me, without faster than light travel, dragging our meat bags around to 'nearby stars' does not seem practical. I will grant that only greed and politics prevent regular service to the moon, it is they that make it seem as distant as an extrasolar planet.
“He’s not deformed, he’s just drunk!”
Self-driving cars.
As an extension: Robots with vision and generalized capabilities.
Generalized AI.
Space resources.
Extreme health improvements.
Nanotech.
3D printers is a small detail in the grander picture (though important).
Um, yes, the industrial revolution is certainly waning. But we've experienced the digital revolution (computers) and the information revolution (the Internet) since then. The Renaissance before that and the agriculture revolution, and that thing where they invented tools from rocks were all similar "big changes" that are still having ramification but have more or less played themselves out. The rate of revolutions has increased so much that many don't see the difference between the digital one and the information one. All of them more or less depend on the technology of the one before it.
The change from horse'n'buggy to automobiles took a decade. Think of the cell phone today compared to the one in 2003. Everyone is walking around with a amazingly fast, ultra-connected computer in their pocket. Honestly, the biggest hold-up is the culture shock. Nobody is really using those computers as much as they could, and the guy that suggested "hey, how about we actually use these cameras that we carry around" gets labeled as a "glasshole".
So yeah, just sit there complaining that the industrial revolution is waning while you instantaneously communicate with a distributed crowd spread out across the world on a whim.
Modern enthusiasm for advances in technology seems to be limited mostly to whatever the latest smartphone is. Also, the people clamouring for those more advanced smartphones also typically have no clue whatsoever about the actual tech specs of them and are typically just being led around by the nose by marketing.
Or, alternately, modern enthusiasm for technology is directed towards products that can be profitably mass-produced and are within the financial means of the average middle-class consumer. The Concorde was both expensive and money-losing, and the side effects (sonic boom) were more than most people wanted to deal with. (Although I sometimes wish we could use the same logic to ban Bluetooth headsets.)
Unfortunately there are lots of technologies like this, where the know-how and manufacturing capability exists, but the economics and other practical aspects make it unsustainable. I don't think it reflects negatively on modern consumers that they aren't willing to support huge, expensive projects like this, or the International Space Station, etc., simply because technology enthusiasts think they look cool. Having been on intercontinental flights in both directions in the last year, I would love if I could cut the flight times in half. But neither my budget nor my employer's budget would allow me to take the Concorde if it were still in flight, so I don't know why I should be excited about that idea, any more than I'm excited by the availability of fully-reclining seats.
No sane race ever will do that
So, homo sapiens will be the first.
But we as a species are still quite capable of it. Concorde was basically a passenger jet with military spec engines; expensive as hell and incredibly noisy, never exactly a great commercial idea. Basically just another penis-waving contest for the British and French governments. Both the engines and the technology to make the vehicles are still available (and massively improved), it's just there's less appetite for intra-governmental penis waving than there was a few decades ago.
Technology continues to march onwards, and I'm sure supersonic passenger flights will return as soon as the technology reaches a point where it is commercially viable. Just because people prefer to spend their money on pocket-sized super-computers (by the standards of the date when Concorde first flew) than marginally faster trans-Atlantic travel, doesn't mean the world is entering a technological dark age. Quite the reverse, in my opinion.
I see everyone is keeping abre...oh never mind.
I rather liked the sci-fi "Fermi Answer" given in Ian Douglas's Heritage/Legacy/Inheritance trilogies: a xenophobic race with a massive Darwinian survival complex decimates every other species that gets close to star travel technology and literally bombards them back into the stone age.
Or perhaps even more likely there's just nothing to detect out there because their "indistinguishable from magic" technology doesn't operate in ways we can detect and all of their EMF shells from bygone eras passed us long ago. And they just have nothing to say to a bunch of primitives like us.
Yeah, but 11 years ago getting from NY to London in less than 4 hours was an everyday thing (if pricier than other flights). Now it's unheard of.
Yes but it was sort of like the pony express shutting down their rush service because the telegraph arrived, maybe that sucks if you wanted to send a package but for the 95% that wanted to send a letter the telegraph was faster and better. Not every aspect of every old service is going to be preserved by the new ones, there will always be some regressions in the overall picture. Even though we're making incremental improvements I doubt we'll see any revolutionary changes in things like jet propulsion, internal combustion, gas turbines and whatnot - it's just minor tweaks to squeeze more efficiency out of it.
The overwhelming number of changes I expect is for things to get smaller, smarter and for more and more things to go electronically rather than physically and applying brute force. Maybe you get another 5 mph on the interstate but the main difference is an AI that drives itself. My dream of "real technological development" would be things like having nanobots to destroy bacteria, viruses, toxins, cancer cells, cure genetic diseases and prevent aging on the cell level. In the future maybe we all have personal assistants like only the rich have today, only they're robotic. It couldn't be done today because to have servants somebody would have to be the servants, but we could all have a robot the way we all have cell phones.
I'm not going to bash the system we have today, I can go down to the grocery store and buy a finished meal, pop it in the microwave and put the dishes in the dishwasher but it certainly could be taken to the next level where I just tell a robot I'd like spaghetti bolognese today and it'd shop, cook like a professional chef, serve and clear the tables when I'm done. Having a washing machine and a dryer is also rather relaxed, but again being able to throw dirty clothes in the bin and have them sorted, washed, dried, ironed if applicable and put back in the closest by themselves would be even better. Roombas and electronic lawn mowers are just a shadow of what robot housekeepers and gardeners could be. In short, even if I don't see flying cars on the horizon I see plenty things that could make life in 2013 seem rather primitive compared to 100 years from now.
Live today, because you never know what tomorrow brings
I don't think sending self replicating machines would be any more "evil" than sending the self-replicating people that would design them. With a machine you could at least tell it not to wipe out an indig population in an conflict over mutual survivability. You can't expect the current model of humans to do that.
"The Adobe Updater must update itself before it can check for updates. Would you like to update the Adobe Updater now?"
Passengers on a manned flight at 1g acceleration/deceleration would experience it as only 6.2 years according to this.
Yes, it should also be noted that we've put no humans on the moon but NASA, ESA, Japan, India, China have all had missions to the moon since and Russia is also planning new missions after they stopped the Luna program in 1976. Mostly what we lack is a compelling reason to send people, it's been done and even repeated a few times so it's a bit like after the first 10 people had been on Mount Everest there's not really much to be proven that we could climb it again. I'd say go straight for Mars, break some new ground not just revisit the old ones.
Live today, because you never know what tomorrow brings
Still, if we ever manage to get our act together well enough to actually build something like a generation ship, 22 light years away is pretty close, relatively speaking.
Voyager has been underway for 36 years and is less than 0.002 light years from earth so it's 10,000+ generations away unless we can go much, much faster. And the concept of generation ships is exactly the opposite, they're massive constructions big enough to sustain a civilization that move very slowly between stars. If we send "humans" I expect it'll be frozen embryos or electronic DNA sequences to be reconstructed on site on a massive rocket ship that'll still take hundreds of years. A light year sounds so short until you realize that if you've traveled 7.5 times around the world you've gone one light second. Only 31,556,925 more to go in order to make a light year.
Live today, because you never know what tomorrow brings
100 years of travel for 22 light years away.
That's 50 years of acceleration and 50 years of deceleration to travel 22 light years.
So you have to accelerate for 50 years and travel 11 light years in the process.
What's the calculated acceleration?
22 light years is 208,200,000,000,000 km.
Average speed to get there in 100 years is 208,200,000,000,000 km divided by 3,153,600,000 seconds, that's 66019.8 km/s. You need to reach that speed in 25 years of acceleration. That's 0.08 m/square second. Easily achievable, provided you don't have to carry half of Earth's mass in fuel. I think even ionic drives can get that sort of acceleration.
Ideally, considering an acceleration of 1g (constant, disregards time spend in orbit or maneuvering around, etc) you could reach 283,940 km/s in exactly 11 months (335 days).
Now all we have to do is come up with a perfectly working Bussard reactor... (http://www.ibiblio.org/lunar/school/InterStellar/Explorer_Class/Bussard_Fusion_systems.HTML)
...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
Given that the only solar system we have even partially explored has at least one potentially habitable planet, why is the constant assumption made that te vast majority of other systems are entirely uninhabitable? Are we really THAT arrogant to think our system is so unique? Based on the evidence in our sample size of one, surely the logical assumption would be that there are plenty of other similar systems?
I run: Windows, OS X, Linux, FreeBSD. Just because you have a hammer, doesn't mean everything is a nail.
Contrary to popular belief, no government funds are allocated for its SETI searches
True as of 1995, when the government withdrew support. Not true for many years before that. Personally I think we have plenty enough issues to deal with at the moment that we should keep it that way for now. My point is this article is an "interesting factoid" but to all but a small minority of astrophysicists and enthusiasts is not exactly "historic"...
Self replicating machines don't have to be intelligent. Even if they only replicate some kind of marker or beacon to plant as they go. The only way to get ahead of the sheer numbers is to spend time planting seeds and signposts with directions to the other habitable planets. Give races something to shoot for and see if they show up.
For every habitable but uninhabited planet we find, the human race becomes more and more special. I don't want to be that special kid...
Dude, I never said it was practical, or that we'd be doing it.
This is an article about astronomers discovering new planets. In their parlance, they are 'nearby'.
Nobody is saying "close enough to get there", they're saying "holy crap, on a galactic scale, that's pretty damned close".
The insurmountableness of the distance isn't what's the point, because nobody is yet talking about surmounting it. The cool part is that they've found it, 3 of them in fact, a 'mere' 22 light years away, all of which could be in the zone where liquid water could exist.
The universe must simply be teeming with planets which have the potential to have life as we know it (or at least chemically similar enough that we can postulate its existence).
We may not get there, but at this moment light from Sol which left in 1991 is reaching these planets.
That, my friend, is some heavy shit.
Lost at C:>. Found at C.
There are a lot of potential answers. Many of them are negative, but some of them are only "sort of" negative. E.g.:
1) The population is plugged into the local analog of the cloud, and doesn't want to put up with the low latency required by interstellar travel.
2) Artificial environments are so much nicer than natural planets, that nobody is interested in them.
3) TV is already one of the more effective suppressers of birth-rate. The internet is a close second. So populations just stop growing. People have more interesting things to do than taking care of kids.
4) An authoritarian government doesn't want to allow colonies to escape to breed rebels. And it's effective. (N.B.: This could be a welfare state, a plutocratic state, or any of various other varieties, and perhaps different planets have different choices.)
5) Perhaps many races can't live in low gravity, or can't stand the stresses of liftoff.
There are, of course, lots of more negative answers, like resource depletion, gray goo, etc. But we don't need to presume that the answer is always the same, or even that we know all the potential reasons yet. I've heard one argument from economics that because of intrest it's impossible for any interstellar colony to ever pay off the costs of founding it. Maybe. Or maybe that's just another hurdle that makes things more difficult. Many species may have a fear of heights or of falling that makes space flight unendurable.
Note that each of these answers only reduces the proportion of races that will engage in interstellar flight....or at least will impinge on us after doing so. And there are many other answers.
Here's another one: We may be among the first generation of planets with enough heavy metals to produce a form of civilization that can lead to space flight.
That said, do note that "super earths" are not a good place to develop spaceflight. The Earth itself is heavier than optimum, but this much gravity may be needed to hold onto viable development conditions. And how important was the moon? Some arguments have held that not only the existence of the moon, but the way that it was captured is crucial. (Note that it stabilizes the Earth's axial tilt.)
So, while I find the Fermi Paradox troubling, I don't find it insoluble.
I think we've pushed this "anyone can grow up to be president" thing too far.
And I thought my internet was slow in the 90s.
Voyager has been underway for 36 years and is less than 0.002 light years from earth so it's 10,000+ generations away unless we can go much, much faster
Ion engines have been demonstrated to work. Solar sails may also be practical for acceleration in the inner solar system. Accelerating at a very conservative one ten/thousandth of standard gravity, a craft using some such constant acceleration system would be going faster than Voyager 1 in less than 7 months even without a gravity assist. After accelerating as long as Voyager has been, it would be travelling more than 60 times as fast relative to Earth. That would make for a trip of about 6500 years. That's still plenty of generations and is certainly a longer term project than anything humans have ever undertaken, but it's at least scraping the edge of the realm of possibility.
The Concorde was both expensive and money-losing, and the side effects (sonic boom) were more than most people wanted to deal with.
The Concorde was expensive mainly because it didn't go into mass production. The sonic boom concerns were largely ridiculous. It was killed pretty much entirely by the one fatal crash and then 9/11.
if you accelerate constantly a 1g for 11 light years and then decelerate at 1g fo 11 light years it takes 9 years to get there in your rest frame. in earth frame time this is much longer so you cant just come back in 18 earth years, but you can come back in 18 of your own.
Some drink at the fountain of knowledge. Others just gargle.
Maybe because it's easier to expand in inner space vs. outer space. In this case virtual worlds rather than real ones.
That reads like something from Mondo 2000. Sorry.
Life is not for the lazy.
We do have massively improved steam engine technology; do you think that applications where steam is still used are still using technology from the 19th century? Steam turbines are THE key technology in the vast majority of electricity-generating power plants in use today. All that happened there was that new and better technology supplanted it in the "vehicle power" space.
In the space travel field, we're massively more advanced than we were a few decades ago. We have deep space vehicles with ION engines. We have a Mini Cooper sized robot on Mars which was landed by a rocket-powered hover crane. We have a football-pitch sized permanent outpost in LEO. We have a deep space probe about to make the first ever flyby of Pluto and exploration of the Kuiper Belt and Outer Solar System. Since 2008 the first and only probe in history to make a near approach of Mercury has been happily orbiting and collecting data (note: Mercury is officially the most difficult planet in our Solar System to reach).
There hasn't been much Moon golf in the last few years, admittedly, but that doesn't mean that space technology hasn't been making huge leaps forward.
Too bad at least one of these planets is already inhabited by a sentient species.
Maybe we deserve this world ?
That is why we have the Butlerian Jihad to free humanity from thinking machines. "The mind of man is holy".
liberare massarum ex ignorantia, clausa descendit molestie.
We don't seem to have intelligent life on our own planet, why expect it on any other planets?
Relativistic journeys calculator here: http://www.cthreepo.com/lab/math1/ Gives 6.2 years (moving frame) or 24 years (earth frame) to get there, assuming constant 1G accel, deccel. I've spent longer (subjective) than that waiting for a British train.
Does the calculator account for speed of light limitation? (you can't go faster that 296K km/s)
I think it does, my manual calculations got me pretty close to that.
Ideally, for a human crew, the ship should alternate acceleration and deceleration so that the perceived gravity is always at 1G. Otherwise, you would accelerate for 1 year, then spend 4 years in zero gravity, then decelerate for 1 year at 1G, which is highly NOT recommended.
...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
Others have chewed over this calc in more detail, different subthreads. To increase perceived G you can always spin the ship. Also, the relativistic round trip doesn't require high peak acceleration to be doable in 6.2 years moving-frame, but it does require *massive* speed: as others have said, once you have got up to 0.6c (relative to the galactic frame) the vague fluff of stray protons etc that are floating around in deep space starts to look like concrete. The main problem for the moment is reaction mass: the Apollo rockets were mass ratio > 19:1 [(fuel+reactionmass):(everything else)]. To burn for twice as long you need to square the fuel, because you are also carrying your reaction mass. There is a lot of loose talk about ramscoops, but they seem like a pretty insane engineering challenge: the practical solution that seems more likely is to develop a super-dense energy storage technology like antimatter, so that reaction mass can be pushed out harder and we don't have to carry as much of it. Once that happens, ramscoops might be the next step but interstellar probes at least would start to make sense without them. AFAIK a human-survivable round trip to gliese (20-40 years, moving frame) would be doable quite soon using nuclear engines such as UF6-water design.... but those babies are not certified for terrestrial launch. Frankly I wouldn't even want one in orbit around my home planet thankyou very much.
It has to be the timespan of technological civilization. For all we know, there should be no proper civilisation on Earth in few hundred years. Tragedy of the commons will make sure of that. It makes sense for everybody to exploit Earth in short term instead of trying to branch out to space in any real way. And when at some point it will be obvious that it doesn't scale, there will be not enough free/cheap resources available to make that jump. And then big asteriod will appear...
That is, if we don't nuke ourselves into oblivion beforehand in name of some ancient deity...
Putting 1000 people on Mars/Asteroid Belt in self-sustaining environment would probably cost same amount (of cash/energy/resources/whatever) as feeding billion of people on earth for their lifetimes. As long as people think that maximizing earth population is overall goal of mankind, there is no chance of any change. And we have it encoded in our genetic and memetic makup. And probably same happens for every civilization out there.
Regarding self-replicating probes... We might have been hit by one 4 billion years ago - DNA+microbes are a lot better nanomachines than clockwork automatons.
And how important was the moon? Some arguments have held that not only the existence of the moon, but the way that it was captured is crucial. (Note that it stabilizes the Earth's axial tilt.)
So, while I find the Fermi Paradox troubling, I don't find it insoluble.
Interesting point. But from a sample of one, one cannot do science. As the planet formation models from before the exoplanet discoveries show, one cannot do viable science based on a sample of one.
Here is how it will work: we will be able to detect spectra of planets within the next 50 years. Based on that, live will be found on many, few, or none. Based on that the models will be adapted, and all nerds on /. in 2060 will fail to understand how we in 2013 did not see how it all really worked, as it's so obvious.
Some arguments have held that not only the existence of the moon
One of my favorite ruminations of this sort is in AE Van Vogt's "The Voyage of the Space Beagle". At one point the titular intergalactic ship lands on a remote planet on the rim of the galaxy, which has only a single rocky planet with no moon. A highly advanced civilization once lived there but died out - because they had no moon, no nearby rocky planets, and no stars with planets within hundreds of light years. So they had no "stepping stones" to develop interplanetary travel, and never made it to interstellar travel. Humans, on the other hand, were able to mount a manned mission to another body within 70 years of developing flight - just because it's so damn convenient. And Mars provides a convenient (if vastly more difficult) next step.
...Or a Bussard Reactor, which uses interstellar Hydrogen as fuel. Basically, you don't carry the fuel with you, but gather it as you go. An even more interesting feature is that the faster you go, the more fuel you get...
Of course, this all is highly theoretical at the moment, but finding super-Earths so close (astronomically speaking) should only encourage research efforts in that direction.
...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
Passengers on a manned flight at 1g acceleration/deceleration would experience it as only 6.2 years according to this.
AC's get no respect, especially when gamers can game their replies for mod points by trumping the original post about an an idea above your comment. If you're into moderation rep, then guessing the right comment to reply to is a gamble. Better luck next time.
Yesterday's Weirdness is Tomorrow's Reason Why
All true, but not entirely fair to the Concorde since you're comparing modern airliners to a 35+ year old aircraft. Back then, the efficiency gap was much smaller. If development on supersonic passenger craft had kept up, the gap would have stayed smaller even though the advantage would always go to subsonic craft (until you start getting into the area of sub-orbital shuttles).
Fuel consumption also effects range. So, there is a reason the United States does not have any supersonic bombers.
Well, I would say that there is a reason and it's called missiles. I would say that, except for the B1-B. It's slower than a Concorde, but still supersonic, and it has a range of 7000+ miles.
22 light years... These guys have seen the entire run of MacGyver by now. Let them figure out how to get here
“He’s not deformed, he’s just drunk!”
OK, so I gave a crude, nonrelativistic calculation of how much energy increase would be required to accelerate from 500mph to 1/2 the speed of light.
I came up with a number, based on the nonrelativistic equation "E=1/2 m * v^2" and added the remark that my estimate was off because of my neglect of relativity.
I explicitly deny that "goes up v^2 because of friction" is true. Furthermore, the relativistic equation isn't even that hard. Let's start with this:
E_kinetic = m * (gamma-1) * c^2 where
gamma = 1/sqrt(1-v^2/c^2)
For 1/2 speed of light, (gamma-1) = 0.1547.
For 500mph, (gamma-1) = 2.78 x 10^-13.
To compare the two, note that
E_kinetic(1/2 c) / E_kinetic(500mph) = (.1547/2.78x 10^-13)
which yields an energy ratio of 5.56 x 10^11.
So to increase "normal" transport speeds from 500mph to 1/2c, we only need to use 556 billion times more energy.
--PM
Well there are inhabital planets we can use if we screw up ours. Thats good and all but how do we get there? 22 light years is a long way. We'd need a faster than light speed meens of travel or a neer light speed travel and advance cryopreservation technology.
Well, I must say I'm really grateful to you for the perfect demonstration of the Dunning-Kruger effect.
This is it:
From Wikipedia, "The Dunningâ"Kruger effect is a cognitive bias in which unskilled individuals suffer from illusory superiority, mistakenly rating their ability much higher than average."
And you're an extremely illustrative case, because even though about four people told you that you were wrong (some more politely and some less), you PERSIST in your belief that E != 1/2 m v^2 (approximately).
I mean, we collectively didn't even manage to inject enough doubt into you that you'd take the trouble to look it up instead of continuing to support your mistaken position in public. Either you're a troll, or you're a REALLY textbook case of Dunning-Kruger.
As for your car, do you REALLY think that you use the same energy every second, continuously and linearly like you claim? I mean, don't you HEAR the engine rev up to higher RPM before it (or you) shifts gears down again? D'you know what that higher RPM means? It means more power (and power, for your information is defined as energy per time).
As for my calculation of some 500 billion times more energy required to accelerate to 1/2 light vs. 500mph, I showed my work, and you can find the basic equation I used on:
http://en.wikipedia.org/wiki/Kinetic_energy#Relativistic_kinetic_energy_of_rigid_bodies
Anyway, I'm going to see if I can preserve this thread as a case study in Dunning-Kruger (or perhaps internet trolling), though even if you are a troll, it's STILL a great demo of Dunning-Kruger.
--PeterM