Earth's Corner of the Galaxy Just Got a Little Lonelier 224
Hugh Pickens writes "Only four stars, including Barnard's Star, are within six light-years of the Sun, and only 11 are within 10 light-years. That's why Barnard's star, popularized in Robert Forward's hard-SF novel Flight of the Dragonfly, is often short-listed as a target for humanity's first interstellar probe. Astronomers have long hoped to find a habitable planet around it, an alien Earth that might someday bear the boot prints of a future Neil Armstrong, or the tire tracks of a souped-up 25th-century Curiosity rover. But now Ross Anderson reports that a group of researchers led by UC Berkeley's Jieun Choi have delivered the fatal blow to those hopes when they revealed the results of 248 precise Doppler measurements that were designed to examine the star for wobbles indicative of planets around it. The measurements, taken over a period of 25 years, led to a depressing conclusion: 'the habitable zone around Barnard's star appears to be devoid of roughly Earth-mass planets or larger ... [p]revious claims of planets around the star by van de Kamp are strongly refuted.' NASA's Kepler space telescope, which studies a group of distant Milky Way stars, has found more than 2,000 exoplanet candidates in just the past two years, leading many to suspect that our galaxy is home to billions of planets, a sizable portion of which could be habitable. 'This non-detection of nearly Earth-mass planets around Barnard's Star is surely unfortunate, as its distance of only 1.8 parsecs would render any Earth-size planets valuable targets for imaging and spectroscopy, as well as compelling destinations for robotic probes by the end of the century.'"
But can it detect a space station? (Score:5, Funny)
Could be a local hangout.
Look at the bright side (Score:3, Interesting)
A lack of planet on a nearby star does not mean there is nothing around the star
There might still be fragments of ice / rocks / whatever that humankind can use to construct an artificial planet of some kind
Plus, the lack of existing planet means we get to create one, with our own design
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Plus, the lack of existing planet means we get to create one, with our own design
Thats what i was pondering.. i'd mod you up if i could.
Re:Look at the bright side (Score:5, Insightful)
A lack of planet on a nearby star does not mean there is nothing around the star
There might still be fragments of ice / rocks / whatever that humankind can use to construct an artificial planet of some kind
Plus, the lack of existing planet means we get to create one, with our own design
Yea, make our own planet. Simple! This got modded 5 Insightful? Why not make another Earth in our own solar system? It would be way easier to do it here where all the resources are, instead of in a distant solar system. Or even easier, crash asteroids from the asteroid belt into Mars to create an Earth size planet. Why don't we do it? Because it would be freakin' impossible for any beings without near God-like technological powers.
Re:Look at the bright side (Score:5, Funny)
I do hope they'll add fjords. They give a planet character.
Re:Look at the bright side (Score:4, Insightful)
"Why don't we do it? Because it would be freakin' impossible for any beings without near God-like technological powers.
People not so long ago would have said that about many of the things we take for granted today. Try telling someone a couple of hundred years ago that we'd build aircraft that could carry hundreds of people at 2/3 the speed of sound to the other side of the planet in a few hours, or that we'd be able to pull a small device out of our pockets and talk instantly to someone anywhere on earth, or that we'd be able to send a sophisticated robot to Mars to explore and conduct science experiments. Creating an artificial planet isn't essentially that hard, it just requires a level of technology beyond where we're currently at. Get to a stage where you can send out self-replicating robots to collect and process asteroids for you, for example, and it might look a bit less daunting. And there's no particular reason to believe that we won't eventually develop such technologies.
Re:Look at the bright side (Score:5, Insightful)
This is exactly what I came here to say.
One thousand years ago, the peak of technology was a powder that would explode when ignited, that could propel a small projectile in a general direction a few hundred feet. Today, the peak of technology is dropping a laser-armed nuclear-powered semi-autonomous wheeled laboratory from a rocket-powered flying crane onto a precise target from 150 million miles away.
By the time we have the capability to load up humans and send them 1.8 parsecs away before they (and any descendents) die, we might just have the technology to build an artificial planet, or at least a large structure capable of artificial gravity, a self-sustaining ecosystem, and harvesting materials from whatever asteroids are nearby. It does not need to be as big as the Earth or support as large a population, but it'll do for a while until technology improves further.
Re:Look at the bright side (Score:5, Funny)
capable of artificial gravity,
You want some faster than light travel with that?
Or perhaps telekinesis?
Re:Look at the bright side (Score:5, Funny)
You want some faster than light travel with that?
Or perhaps telekinesis?
You read my mind!
Re:Look at the bright side (Score:5, Informative)
capable of artificial gravity,
You want some faster than light travel with that? Or perhaps telekinesis?
Inertia expressed as centripetal force will do just fine, thanks.
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capable of artificial gravity,
You want some faster than light travel with that?
Or perhaps telekinesis?
Artificial gravity can easily be implemented with acceleration. Pretty much every amusement park out there have a "large" structure capable of artificial gravity. They usually create a gravity-like force out from the center but sometimes they create a transient gravity-like force, either upwards or downwards from earth to increase or decrease the real gravitational force you fell form the planet.
Faster than light travel is a bit harder since traveling at light speed isn't supported by current models. If the
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I just want a big spinning thing.
Structural engineering (and the related chemistry, metallurgy, and industrial engineering) technology will have to improve, of course, but it is reasonable to build a large spinning wheel as a habitat around a central weightless work area. It doesn't need to be nearly as much as Earth's gravity to be useful, and the subsequent generations that spend their whole lives on the craft will adapt (mentally first, then ever-so-slowly physically) to the altered environment.
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Now that is within the realm of possibility, as long as it's at a small enough scale that it's doable. We can probably work around how this differs from gravity (your head being lighter than your feet, coriolis effects, curvature going the wrong way), or adapt.
Artificial gravity as in Star Trek, on the other hand, is not, at present, something it's even worth working towards. If we get a new set of physics, then we can revisit that -- just like human flight needed a new set of physics before it could beco
Re:Look at the bright side (Score:5, Funny)
No thanks, I had some neutrinos for lunch, and boy did they go right through me!
Re:Look at the bright side (Score:5, Funny)
Come one, artificial gravity is easy. You use a simple quantum graviton emitter to pull gravitons from the gbrain and emit them in concentration creating an artificial gravity field.
Everyone knows that.... Wait, what year is it?
never mind.
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Re:Look at the bright side (Score:4, Insightful)
Doesn't sound like you appreciate the difficulties of doing an interstellar probe. It's not like silicon chips, in which we've seen astounding improvements. We simply can't do it, not now, and probably not in the next 20 years or even 100 years.
Currently, our fastest escaping probe is Voyager 1, at about 17 km/s relative to the sun. At that rate, a probe will need about 70000 years to reach Alpha Centauri. Suppose the velocity we can give probes improves by a factor of 100, which is assuming a lot. (For one thing, gravity assists would be of little value.) That's still 700 years. We have no experience making machines that can last that long. Our civilization might not last that long. We need perhaps 1000 times the velocity, then we're talking only a 70 year wait.
To achieve 1000 times the velocity is not a matter of 1000 times the fuel, it's 1000^2 times the fuel. It's even worse than that, if the probe has to carry its fuel. No matter how we accelerate the probe-- whether with on board ion drives, nuclear bombs, light sails, or something else-- that's such a huge amount of energy that none of these ideas are even remotely feasible. That means it will have to be slower, which puts us back to the problem of how to build something that can last the 1000 plus years such a trip will take. There are many other problems, such as communication, but the primary one is simply the distance. I wouldn't hold my breath for science fantasy either. It's not at all likely we will invent warp drive or some other means of FTL travel.
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Nature abhors a pessimist...
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cjsm only excluded beings that did not possess god-like technological powers. So I guess we're OK, since Western civilization was considered god-like from the time of the conquistadors.
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Get to a stage where you can send out self-replicating robots to collect and process asteroids for you.
I'll pass on the self-replicating robots; we all know what happens next.
Re:Look at the bright side (Score:5, Insightful)
Yea, make our own planet. Simple! This got modded 5 Insightful?
The Mormon Moderation Front?
Seriously, I can't think of anyone else who believe that humans will create planets. No, this is not flamebait or trolling - it really is the only ones I can think of that might see this as a possibility, although not while still human.
And if there really are someone delusional enough here to think that we could create our own planet while being mortal humans, you really need to think about the scale here. It's not just huge, it's immense. We only scratch the surface of this planet.
If we found Mount Everest sized rocks (~3x10^15 kg) in a solar system, we would need around 2 000 000 000, that is 2 milliard (or billion for those who use the short system) of them to create a planet with Earth's mass (~6x10^24 kg). Imagine the power and time needed to move one Mount Everest. Each Chomalungma sized rock is about 28 milliard (or billion in the short sytem) times the weight of the space shuttle.
And we're not just talking scale here. Think about how you would adjust the orbital speed of the mass you assemble so it would stay in orbit as you add to it. Or how to cool it down from all that kinetic energy -- how long did it take Earth to cool down? Or how to survive the flares of Barnard's Star?
Niven and Lucas make great space operas. But we have to admit to some limitations. Come back in a few million years, and whatever species have descended from us may have a different opinion. But us? No, we have no chance.
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I think, given that you're writing in English, it's perfectly safe to say "billion" and not specify "short system" every time.
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Everything is impossible until you figure out how to make it possible...
Re:Look at the bright side (Score:4, Insightful)
Yeah I mean what's with people who think humans can fly? There are just things that humans were not meant to do!
Everything is impossible until you figure out how to make it possible...
This isn't just a technical issue, unless Newton, Carnot and Einstein were all wrong in pretty radical ways.
Scoffing at building a planet is more like scoffing at someone who says he can eat the moon. It's not just a question of getting and preparing the moon - there's not enough time for it to happen in.
Re:Look at the bright side (Score:4, Insightful)
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Everything is impossible until you figure out how to make it possible...
It's not impossible -- it's just really, really improbable given the current state of our energy and propulsion technology, and there's not much big propulsion tech on the horizon that would seem likely to change that anytime soon. VASIMR is pretty promising for small manned spacecraft (and even more so for large robotic spacecraft) but it's basically in the realm of ion engines -- high efficiency, long run times, but relatively small thrust even compared to fuel/oxidizer engines. Even Orion-style propuls
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Planet? Not so hard really, use well targeted nuclear explosions to adjust asteroid orbits just enough to induce collisions... a lot of collisions.
Oh, you mean a habitable one? That's going to be a tall order. A planet wouldn't be so hard to do, you just need to put enough matter together and gravity will do the rest... in a few hundred million years. The habitable part is much more tricky. You need water, plate tectonics, magnetic field, inert atmosphere, ozone layer, etc.
On the other hand, we could b
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Niven and Lucas make great space operas. But we have to admit to some limitations. Come back in a few million years, and whatever species have descended from us may have a different opinion. But us? No, we have no chance.
We are hardwired for optimism, for better and for worse. And future milestone breakthroughs are very hard to predict. Some predict an accurate simulation of the human brain is only several years away. Strong AI shouldn't be too far off after that. Strong AI will expand the sphere of whats possible, technologically. But we human beings are most defintely very primitive. IMO, we have never possessed the type of ethical wisdom, nor moral courage that would allow our species to survive well into the future.
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Getting there will be much harder then moving a few rocks around.
Um, no. A planet isn't just "a few rocks". The scale is immense, and we're bound by the laws of physics and thermodynamics.
Never mind where we would get the energy to accelerate and decelerate such masses from, it would likely take thousands of millions of years to assemble those "few" (thousands of millions) gargantuan rocks and have the new planet cool down enough to be ready for terra-forming.
Getting there isn't even in the same fantasy as creating a planet. There are orders of orders of magnitude dif
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billion is a word (Score:2)
What is your resistance to using the work billion? It isn't a dirty word.
Also, I agree with you mostly on this. They only way I can see people making a planet is by making self replicating robots that can mine the universe for energy and minerals and have them do all the work. If they can build themselves expoentially and are somewhat networked they could be "told" to go forth and multiply and make us a planet. It still wouldn't be a weekend endevour though.
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Saving all known life in the universe seems like a pretty important thing, the universe would be pretty boring without it.
No, it wouldn't. Per definition, there would be no one to be bored.
Re:Look at the bright side (Score:5, Insightful)
Why not make another Earth in our own solar system?
I'd prefer them to use Barnard's star for beta testing the process.
Creationists (Score:5, Funny)
Plus, the lack of existing planet means we get to create one, with our own design
I wish you damn creationists would stop posting here!
Re:Look at the bright side (Score:5, Interesting)
Re:Look at the bright side (Score:5, Insightful)
This is actually pretty much true.
By the time we have the technology to smash together enough rocks that it can hold an atmosphere with its natural gravitational force, we won't need to live on a rock with enough natural gravitational force to hold an atmosphere.
That godlike amount of effort could be spent doing something more practical.
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You've completely missed the point. NASA has a hard-on for searching for signs of life on other planets, and an "Earth" in the next solar system would be a damn near perfect place to find life, or otherwise lend credence to the opposition (that says life is unique to Earth, or at least not the oh-so-common scenario which most contemporary astronomers claim that it is).
If we just wan
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Good point. Maybe there was a planet, but the locals ripped it apart to build a Ringworld. There is no way to detect that from here with current technology.
Results did not rule out Earth sized planet (Score:4, Informative)
A lack of planet on a nearby star does not mean there is nothing around the star
And, even more to the point, a lack of a planet larger than ten times the Earth's mass in an Earth-like orbit, or two times Earth's mass in a close-in (ten day) orbit says nothing about the presence or absence of Earth- mass planets, unless you have a well-accepted theory showing that systems with Earthlike planets must also have Jupiter-like planets, which is a theory we don't have.
That's according to what the actual article says-- ignore the Slashdot summary, it's wrong. http://arxiv.org/abs/1208.2273 [arxiv.org]
And, worse, the mass detection limits are limits on m*sin(i)-- if the orbits are inclined, the planet masses that couldn't be detected would be even larger. (in the limit, if the orbit is face on, it wouldn't have detected planets regardless of how massive they are)
Overall conclusion: This puts limits on planets around Barnard's star, but did not have the ability to detect, and thus did not rule out, Earth-mass planets.
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There might still be fragments of ice / rocks / whatever that humankind can use to construct an artificial planet of some kind
The point is that there is nothing in the "life zone", where you find liquid water, so pretty unlikely there is any life in the system.Which is about the only thing that would justify the gigantic cost of going here.
If we're going to build habitats from scratch, we have plenty of rocks in our own system, asteroids, moons, then the Kuiper Belt. As long a we can hold off from killing ourselves, we could house trillions in this system in the next few thousand years.
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There is an interesting aspect towards Science Fiction... The fact that it is Fiction.
fiction [fik-shuhn] Show IPA
noun
1.the class of literature comprising works of imaginative narration, especially in prose form.
2.works of this class, as novels or short stories: detective fiction.
3.something feigned, invented, or imagined; a made-up story: We've all heard the fiction of her being in delicate health.
4.the act of feigning, inventing, or imagining.
5.an imaginary thing or event, postulated for the purposes of
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Hmmm, and how much science fiction has become true within a century or two of it being written? Traveling to moon? Did that. Created giant subs capable of traversing the world's oceans? Did that. Went to Mars? We're pretty close. Cybernetics? Robotics? The author that came up with those lived to see them start to become real.
Alpha Centauri (Score:5, Interesting)
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Re:Alpha Centauri (Score:5, Funny)
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No, since we know of the existence and orbital period of the two bodies, all it takes is a little extra number crunching to removes those wobbles from the data. It's pretty straightforward signal analysis. That the frequency of those wobbles will be different from the frequency of planetary wobbles just makes it easier.
Re:Alpha Centauri (Score:4, Funny)
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How big a telescope would need to be, in order to be able to find streetlights on a planet 10 light years away, either by looking for an artificial spectrum, or for a frequency of the order of 50Hz, assuming a continent-wide synchronised AC power supply.
Assuming you just want a big telescope that can resolve something on the scale of a streetlamp, 10 light years away...
We'll need the small-angle formula and the Raleigh Criterion. The first gives us the angular size of the streetlight; the second gives us th
No planets around Barnard's Star? (Score:2)
Let's just build a 'tugboat' and take the earth with us and hope the core stays hot enough to keep us from freezing solid. Be ready for a very long night.
Re:No planets around Barnard's Star? (Score:4, Funny)
It would be a lot easier to make an interstellar ship out of the moon. We just need to build a large base and then set of a huge nuclear explosion on the other side of it.
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For a moment there, I thought you meant on the other side of the moon from us, rather than from the base. I was already to go "nooooo, that'll crash it into the Earth, you fool!" Then I realised. And posted anyway. Ah well.
yes, that's the ridiculous part of the "nuclear powered moon-ship" plan.
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http://www.youtube.com/watch?v=Csj7vMKy4EI [youtube.com]
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I -probably- read this in Issac Asimov's Science Fiction Magazine.
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It's called "A Pail of Air" by Fritz Leiber from 1951.
The planet was actually earth, which had been torn away from the Sun by a dark star passing through.
It's a nice and rather short story and can be read in full here. http://www.baenebooks.com/chapters/0743498747/0743498747___6.htm [baenebooks.com]
Is it still a possibility? (Score:2)
Could this just mean that it eliminates any orientation other than either pole of the solar system facing Earth? Absolutely no planets seems so suspicious...
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You could still detect a wobble or deflection of light if a planet orbits around the equator or over the poles.
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Could this just mean that it eliminates any orientation other than either pole of the solar system facing Earth?
No, if that were the case, you would still see the star "draw" a little bitty circle if anything sizable is orbiting it.
Re:Is it still a possibility? (Score:5, Informative)
The barycenter of sun-earth is only 300 miles from the middle of the sun.
Keep in mind that Barnard's star is only about a seventh of the sun, and much cooler, so the habitable zone is much closer. An earth sized planet in the habitable zone would have a much larger impact on Barnard's Star than Earth does on Sol.
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It's Masters of Orion 2 all over again! (Score:5, Funny)
Now I'm seriously worried. Every time I played Masters of Orion 2 and I got situated in an area where the closest habitable planet was far away I always got my ass kicked by some civilization that was able to expand quickly. Our only hope is to start developing Deuterium fuel cells, and quickly!
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But in the real world the civilizations don't all start on the same year, so this is a bonus.
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Yep, we are some 2 billion years behind the median.
Look on the bright side (Score:2)
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with no intelligent species within earshot
Including, I should add, on Earth!
Ob (Score:5, Funny)
What do you expect? This end of the Western spiral arm is somewhat unfashionable.
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What do you expect? This end of the Western spiral arm is somewhat unfashionable.
What do I expect?
What do I *expect*!?
I *expect* a freaking restaurant!!
a probe? (Score:2)
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Why would we send a probe instead?
Because canned primates and their support structures [antipope.org] increases mass astronomically.
Habitable? (Score:2)
leading many to suspect that our galaxy is home to billions of planets, a sizable portion of which could be habitable
I guess that depends on your definition of habitable.
Sci-fi vs Science (Score:2)
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I don' t think the Earth could provide the energy needed for interstellar flight as we know it, but in principle the only energy needed to move between (4 dimensional) points A and B is the difference in potential energy between the two points. In practice the only method of acceleration in space we have is to eject 4-momentum in the opposite direction, permanently losing that energy.
We could do a lot if there were some way of manipulating gravity, e.g. a gravitational lens could pull ships about without wa
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Oh you'd still lose a lot of energy, you don't get to win there.
However, the great advantage of artificial gravity would be reactionless drives. That means we wouldn't have to carry around massive amounts of fuel that we're just going to eject from a big nozzle to keep us moving. If you were able to generate artificial gravity, you could have a nice compact energy source like a fusion or antimatter plant and manipulate space-time to create a gradient.
You still technically need fuel for the plants, but the
Masters of Orion 2 (Score:2)
Just restart the game, thats what I do.
This could be a good thing (Score:2)
Really? (Score:2)
Send a probe to another star by the end of the century, really! I'd like what they are smoking. At current technology, that would take about 8,000 years to get there. Using space sales, that might be reduced to 3,000 years. Using a nuclear pulse engine, that could be reduced to 300 years. Of course, they better develop deflector shields, too, because at the velocity of a nuclear pulse engine, a small particle has the potential to destroy the probe given the kinetic energy involved and as we all know, sp
Advertising (Score:2)
Re:Don't need a planet to explore (Score:4, Interesting)
If a solar system has only one thing in it and that thing is mostly just relatively undifferentiated hydrogen, that's going to be less interesting that a solar system with a bunch of things in it. (Regardless of any ideas about colonizing or anything else.) It's certainly still possible that there is something fascinating in that solar system, but at the moment, it would have to be something we still can't detect, so it's hard to get as excited about. Planets are fascinating things. They have interesting geology and interesting compositions. They also imply that there is enough mass for things smaller than planets, like comets and asteroids as well.
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Yeah, but that is not the argument in this story, the argument is not that there are no planets there, the argument is that there are no Earth size (or larger) planets are not found within the 'habitable zone'.
This doesn't mean there are no planets, there are no planetoids, there are no comets, there is nothing there. It means there are no planets like this one or bigger within the 'habitable range', which is another thing that we make various assumptions about.
So to us 'habitable' means some range of temp
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Have you ever played Star Control II? If there are no planets to land on you're just wasting your time.
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Over millions of years, sure. It takes a little while to dissipate.
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You say the 700C hellhole of burning sulphuric oceans is "a bit harder" to terraform?
That is a bit of an understatement.
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The advantage of Venus over Mars is that is already has abundant oxygen in the atmosphere, just in a different state than we need it. It's also a lot closer to the sun, so solar power is much more efficient. I wouldn't expect non-domed cities anytime soon, but the materials and resources are there to fuel a domed or underground colony.
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Yes, except the atmospheric pressure at the surface is gigantic and the solar energy that reaches the surface makes it about as bright as Mars. I'd also talk about the sulfuric acid rain, but due to the pressure, it actually doesn't rain below a certain level of the atmosphere.
Venus *might* be habitable if we can strip off most of the greenhouse gasses and reduce the pressure, but it also doesn't have plate tectonics, its whole crust basically inverts when it is time to release heat from its mantle, so tha
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bacteria don't thrive that well at temperatures that melt lead.
That does not fempute! (Score:2)
The more tried method (That humans have done on animals for several thousand years.) is genetic modificaton through selective breeding
Oblig futurama... death by snu snu! http://www.comedycentral.com/video-clips/yttx80/futurama-death-by-snu-snu [comedycentral.com]
(Sorry, it was the first thing that came to mind.)
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Because if it's larger then gravity will make it uninhabitable, and if it's smaller then it can't hold an atmosphere, which again would make it uninhabitable.
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Douglas Adams can't be wrong! This can only mean the ultimate answer isn't 42. Excuse me while I drown my sorrows in a pan galactic gargle blaster.
Don't panic - Adams only wrote about Barnard's Star as like a roundabout. That means, even if there's no planet, there could be an intergalactic truck stop there.
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We still need a fallback planet. We could keep this one in pristine shape and the Sun will simply eat it a couple of billion years from now. Of course, something like a massive collision or interactions with other stars could also well happen well before that.
Never fear, we'll need to clean this planet up long before we can even think about colonization, but the relative costs of space exploration are actually pretty tiny if you look at the budgets, there's no need to cancel the manned space program to cl