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NASA Proposes Warming Mars
hotsauce writes "The Guardian reports a NASA scientist has proposed releasing a gas on Mars to start a global warming of the planet in order to make it more hospitable for life. No word on how much traction this has amongst geophysicists. I wonder how much simulation and testing you need before we feel safe about affecting an entire planet."
Shouldn't be that hard considering how good us humans are at causing global warming!
It's a virgin soil and it has to remain so : we have to much to learn about it instead of polluting it : When Mankind can prove it can live in equilibrium oni Earth, then it can spread elsewhere.
Trolling using another account since 2005.
Ohh, just a few more decades and we'll have a viable test bed right here on earth.
BTW, Edgar Rice Burroughs would approve as the author of the John Carter of Mars series of books which talked about life on the Red Planet.
It's been speculated for many years to reproduce gas emissions on Mars as we do on this planet. The atmosphere was thicker on Mars then it is now; yet you have to go back to the problem that caused the atmosphere to thin in the first place. As it turns out, the core of the planet slowed down or event stop spinning causing the magnetic field to disappear.
Unless the core spins to shield the planet from the solar winds then anything done will only be temporary. The sun will simply blow off any thick atmosphere. Alas a pipe dream to teraform the whole planet unless you take some ideas from the movie Space Balls.
Maybe we could ship all of them to Mars? Well worth the cost if you ask me.
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With all that methane being generated, it should warm the place up quickly
We can't seem to get our outdated shuttles off the ground safely, or keep a permanent space staion running effectively. Is now a good time to tinker with another planet's atmosphere?
"As the intrepid kobold companion continues his journey, he begins to wonder... if priests raises dead, why anybody die?
Its likely already a dead planet... we can use it to test these new processes. What's the worst that can happen? It gets deader? Can't prove any method that complex without actual trials, I would think.
Apparently none, since we are modifying the earth in bad ways every day. Having another planet we can live on sounds like a great idea to me, since this one is becoming less habitable every day.
I Am My Own Worst Enemy
I guess NASA's scienticians have determined there is no life on Mars then? I can't see them killing Martian bacteria just for a little elbow room.
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It's still debatable whether or not global warming can even happen with the amount of gas we are putting into the air.
And so how would you expect that to make any difference on mars? You would be have to be sure of the results to start. Until we know we are global warming here I say we hold off and not try experiments over a whole planet.
And if anybody comes back with a big spidery thing attached to their faces, for ged's sake, DO NOT LET THEM INTO THE HABITAT!
There exists no way of exchanging information without making judgments. --Bene Gesserit Axiom
Where the hell are we supposed to get that much of ANY gas?
How are we supposed to get it to stay there on Mars? If Mars could successfully hold an atmosphere, wouldn't it still have one? I was under the impression that Mars' low gravity and weak magnetic field allowed radiation to strip away any gases on Mars' surface.
http://spot.colorado.edu/~marscase/cfm/terrabib.ht ml contains references to nearly 100 books, articles, papers, etc., on terraforming.
How am I supposed to fit a pithy, relevant quote into 120 characters?
I wonder how much simulation and testing you need before we feel safe about affecting an entire planet. We've been affecting Earth for quite some time. Hell, we're experts in global warming. Bring on Mars!
Excellent!
We cannot control the effects and cost of global warming on our own planet, so let's try it somewhere else and in the long run, reduce costs for earth inhabitants.
Fortunately enough, nobody yet figured out how to make PROFIT with this
I wonder how much simulation and testing you need before we feel safe about affecting an entire planet.
None, apparently, if you're one of those who thinks that the uncertain economic effects of the Kyoto accord are more significant than the uncertain environmental effects of dumping more greenhouse gases into the atmosphere.
Or does conservation only apply to other planets?
"This would take hundreds or even thousands of years. But since the raw materials already exist there, some future space mission could start to turn up the heat in a world frozen for at least 2bn years."
is this a native gas? how would they activate it?
"You get all the fun of sitting still, being quiet, writing down numbers, paying attention...science has it all."
Unless the core spins to shield the planet from the solar winds then anything done will only be temporary. The sun will simply blow off any thick atmosphere.
If you're willing to wait a few million years, sure.
Blaze a trail to the New World
The New Scientist also has an article on the subject.
Isn't the gravity on Mars only something like 1/3 that of earth? Is that enough to support a breathable atmosphere? Our air here on earth is 21% oxygen, so to obtain the same partial pressure I assume we would need something like a 60% oxygen atmosphere. Wouldn't everything (including us?) be really dangerously flammable?
It's a nice idea, but it just won't work. According to the Bush administration, there is no such thing as global warming, thus we would be unable to raise the temps on Mars. ;-)
Todd
Why is NASA so gung-ho about going to mars so quickly? Why not return to the moon so we can learn how to sustain our peeps closer to home?
Last one to open a burger restaurant on Mars is a sissy!
Somehow I suspect that whether it's right or wrong we'll feel just fine about affecting an entire planet with a minimum amount of "simulation and testing". We haven't been shy about affecting the one we live on so what makes anyone think we'll hesitate to start monkeying around with another one.
Appended to the end of comments you post. 120 chars.
I sure hope Khan doesn't find out about this plan. Although, maybe if he does, we can send the dead scripts from Enterprise to the budding planet and resurrect a franchise ...
This is totally irresponsible work by NASA. Climate scientists should know better than anyone the lesson of our imminent climate change crisis. Human meddling with astoundingly complex systems like planetary climate is arrogant well beyond our competence, and predictable only by the law of unintended consequences. Screwing with Mars' atmosphere when we're just beginning to admit that we've already screwed up ours will nearly certainly make that planet harder to "manage" as it becomes more necessary to our human evolution. Humans thrive only in a very narrow band of climate parameters, out of a vast range of possible climates. When they spend a century shifting Mars unexpectedly into a less mutable climate stasis, that is just as inhospitable to human life as it is now, but a different configuration, it will take even more centuries to undo the damage, if even possible. We're just not ready for this kind of work, if we ever will be in the foreseeable future - and the stakes are too high to fool with.
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This post is definitely meant as more of a question than a statement, as I am pretty ignorant of geophysics and the like.
But could someone explain to me why scientists even consider the idea of trying to artificially create a new atmosphere around another planet, and why they think it could work?
The thing I am not understanding is that if Mars is thought/known to have had an atmosphere in the past, and doesn't anymore, clearly there are factors beyond our control that would just cause a new atmosphere to eventually disppear too, right?
The original atmosphere on Mars must have disappeared due to factors such as boiling away, not enough mass to create a strong enough gravitation field to retain it, or perhaps being blown away by solar wind because Mars does have a magnetic field like we do here to deflect it, etc. (By the way, I don't even know if these are real situations that could occur, I am just making them up as examples of things beyond our control that seem to me that logically could maybe have caused the previous atmosphere to disappear.)
So again, this is not a statement but an honest question from someone who doesn't get it- what is different about mars now than a hundred million years ago that makes scientists think it would work now?
4 out of 3 people have trouble with fractions
A Kim Stanley Robinson (SF writer) short story which he later expanded into 3 novels (Red/Green/Blue Mars).
Covers this is a believeable and seemingly plausible way...
One of my all-time favorite SF series, right next to the Gap Cycle by Stephen R. Donaldson and the original Foundation Trilogy by Isaac Asimov.
Goofy, Geeky Gifts and More!
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Get your Ass to Mars!
You're speaking in ignorance.
Solar output correlates better with global climate change than does CO2.
Do a little googling. One example: stanford.edu
Don't bother giving my what ever phony story you have. I've heard them all and I've seen the real data.
Translation: poster's belief is not scientific and fact-based, but ideological and faith-based, therefore additional facts will NOT be considered. Any data that disagrees with poster's preformulated conslusions will be denied as a Papist Plot ...er.... anti-Muslism heresy ...wait... Communist propaganda...got it! ... "right wing lies".
So, Anonymous Coward, if you've seen all the "real data", please give your cutting one sentence rebuttal of the Stanford reference above.
When Mankind can prove it can live in equilibrium oni Earth, then it can spread elsewhere.
Huh? That's suicidal. How about: until we prove we can live in equilibrium on a planet, we must spread elsewhere.
By the way, living on a planet for geolocially long periods of time will require geologic action, not misguided, pristine inaction.
Explain to me how STUDIES are irresponsible? It's not like they are on their way right now with their greenhouse gas factories.
What is irresponsible is not to think about it until it's too late.
I wonder how much simulation and testing you need before we feel safe about affecting an entire planet.
Yeah, because if we screw it up, we might turns mars into an inhospitable desert!
Oh wait.
Reason, free market capitalism, and individualism
But then again, our prime directive is profit at any cost.
If someone says he and his monkey have nothing to hide, they almost certainly do.
I wonder how much simulation and testing you need before we feel safe about affecting an entire planet
It's funny how they're talking about radically changing another world but thing that astonished me the most was the proper use of "affected" instead of "effected" in a Slashdot post.
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on venus?
i'm not joking, it seems to me that it would be energetically MORE feasible to cool things down in venus's atmosphere than it would be to heat things up in mars, and probably take less time too
to heat mars up, you would need a significantly denser atmosphere... where is that coming from?
while on venus, you just need to precipitate certain things out of the already dense atmosphere
it is easier to remove something already there than to introduce something that isn't there
of course, cooling down venus or heating up mars are both huge undertakings
it just seems to me that the thermodynamics of cooling down venus presents an easier challenge in comparison
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
A much more difficult task than terraforming Mars, conceptually, is terraforming Venus.
Sci-fi authors have often implemented plot devices such as impacting ice-laden comets or moons into Venus to cool it, supply water, and spin it up; however this is fundamentally flawed, as the problem the amount of CO2. Furthermore, impacting a comet or moon will impart more energy than it would soak up. Now, perhaps with a large enough impact you could blast away part of Venus's atmosphere; however, this would need to be a very significant impact. Hypothetically, a large near-impacting body that skims Venus's atmosphere repeatedly might be able to take some atmosphere with it on each pass; however, it seems unlikely that you could ablate enough atmosphere in this manner while using a body small enough to control.
Sagan proposed the use of microbes in the atmosphere to absorb the CO2 and precipitate it out, but this suffers from one big fundamental problem: life as we know it requires CHONP, and there's no significant quantities of phosphorus in Venus's atmosphere. Perhaps a simpler form of "life" or nanomachine - even if not self-replicating, but simply mass produced on Earth - could use solar energy to convert CO2 to solid compounds.
In theory, if Venus could be driven into a very elliptical orbit (causing close passes to the sun), the sun would blow off most of its atmosphere. Or, if Venus could be given an extremely fast rate of rotation, the atmosphere could be made to expand to the point where the solar wind can blow it off easily. However, apart from the length of time for the sun to remove the atmosphere, both of these require imparting incredible amounts of energy to the planet.
Another concept has been to use gigantic sunshades to block sunlight approaching the planet; however, planet-sized shades seem a bit far-fetched to build. An alternative that I've seen would be to use gigantic mirrors to focus solar energy on a small part of the upper atmosphere and use the light pressure to encourage particles to reach escape velocity; whether or not this is realistic, I don't know.
Dear Lord: One of your creatures may be hurt tonight. Please let it be the other creature.
Wouldn't the gravitational spin of Mars which causes high temperature fluctuations be a big constraint? How would that be addressed?
Uh, and the risk would be what? That Mars would become uninhabitable?
This should be a raving success. I mean, look at how successful we are at warming up the Earth!
Troll? Hell yeah!
Since nobody owns Mars, and what happens on Mars has no bearing at all on what happens on Earth, then the people who have both the technology and the money to make it happen have the final say. Namely, NASA and ESA (and maybe China and India in the reasonably near future?)
Even if the whole world was a democracy (which it's not), the world at large does not have the means to get there first and claim it... and the certaintly wouldn't contribute to the effort even if they did support it. So nyah nyah to them.
=Smidge=
If we mess up, then we'll have learned a lesson which can be used next time. There's no way to learn how to go about messing with a planet's atmosphere without... messing with the atmosphere! Think ahead: If we can't live there when we need it, we can always mine it for resources.
Black and grey are both shades of white.
Is that your best reason, that it might go wrong?
Sorry but that's dumb. Everything might go wrong. Your house might burn to the ground because of an electrical fault. Does that mean you shouldn't use electricity or that you try to minimise the risk through safety standards and certification? You might hit a wall in your car. Does that mean you don't ride in a vehicle or that you should learn to drive properly and buy a car with various safety features? You might get attacked by a dog (while walking). Does that mean we should kill all dogs or enact laws that make owners responsible for their animals? Your computer might be compromised and be used to store kiddy porn. Does that mean you should unplug all the jacks from the wall and lock the PC in a metal box, or does it mean you should be diligent and use appropriate firewall / antivirus software?
I'm not advocating any crazy experiment on Mars - but if there is a carefully reached and reasonable expectation that something will work and the rewards outweigh the risks, then it should be taken. The alternative is for mankind to collectively cower under the table waiting for the next global catastrophe to wipe us all out.
Besides, who knows what kind of fossel record would be being destroyed by exposing the planet to natural weather forces again.
Yeah right. But to apply your own risk aversion argument, how would we ever know about the "fossel" record? After all, there is a very real chance of mission failure when going to Mars. How can we possibly send people or robots to Mars if the probe could blow up? The same goes for any other human endeavour past, present or future.
Hanging around for something - anything - to be 100% certain (except death & tax) is to piss away any future that humanity might have at all.
There is no life-ending catastrophe even on the most distant horizon.
Well that's clearly false, for a start. What about the death of the sun? Or of the universe?
More importantly, what about the uncertainties? Like nuclear war? Worldwide plague? Asteroid strike?
The fact is, Earth is a single point of failure for the human race, and we can't predict when it will fail or what will cause the failure. The only safe solution is redundancy. Terraforming Mars is the only remotely feasible option in the near future.
Of course this is going to raise the pro- vs. anti-development arguments to try to claim we should do such-and-such for the good of mankind and animals and plants and life, or not do it.
But, like genetic engineering, it is inevitable: humans will become increasingly engineered on the genetic level, that the living space of man will expand to every corner of the earth and beyond..this is our destiny.
But politics will control WHICH humans will do it, who will be the perfect beings, who will conquer Mars, and at what point will a war with Earth break out?
Being anti-genetic engineering or anti-Mars-colonization is like being anti-gun or anti-drug: forces bound to lose because of the great advantages that a sole user of the technology will have, and their power as a group will be unstoppable, whether they are an organized force or not.
I'd really like to expound on this and probably correct some of my wording, but Slashdot isn't generally a place for well-though-out arguments.
I'd settle for replacement by a species that can draft coherent sentences.
"Patriotism is your conviction that this country is superior to all other countries because you were born in it." -- GBS
Anyone else see the irony in someone with the name "ArthurDent" saying that the Earth is not in imminent danger of destruction?
Forget global warning for a minute, earthman, and consider a meteor the size of Texas slamming into us at a few million miles per hour. The effects of that would be, in a word, bad.
Obvious exits are NORTH, SOUTH, and DENNIS.
Nobody is really going to terraform Mars with greenhouse gases. But if you get people to accept the argument that greenhouse gases can cause global climate change, you win the political argument that it can, or does happen here. It forces the question quite handily.
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As seems to be increasingly the case, I already submitted (rejected) variants of this story twice over the past week. I've pasted one of those variants below, which has links to sources far more information than the freakin' Guardian:
Greenhouse gases could breathe life into Mars
MSNBC, New Scientist and PhysOrg report on research by Margarita Marinova and others on using synthetic greenhouse gases to warm the Martian atmosphere and create the conditions for life to thrive. The study focused on fluorine-based gases (dubbed "super-greenhouse gases"), which would be non-toxic, nearly 10,000 times as effective at capturing heat as CO2, and could be made from Martian resources. The research concluded that adding 300 parts per million of these gases would lead to a feedback effect by unfreezing CO2 and water on the surface. According to Marinova, 'Since warming Mars effectively reverts it to its past, more habitable state, this would give any possibly dormant life on Mars the chance to be revived and develop further.' The feasibility and consequences of such terraforming have been debated in the past.
Also, note that contrary to the accepted submission's title, NASA hasn't done any sort of proposal of actually doing this. This is simply cool research exploring a very interesting "What-if".
"Bossting CO2 emmissions on another planet - gee, how the hell are we gonna pull that one off"
I have a '73 Buick I think could do it.
At a given temperature, a gas has a certain pressure and root mean speed (norm of velocity from its kinetic energy). (A bit of calculation can show it to be (3kT/m)^(1/2), where k is Boltzmann's constant, T is temp in Kelvin, and m the gas molecule's mass.)
If the root mean square of the gas is comparable to the escape velocity (2GM/R)^(1/2), the the majority of the gas will only stick around for a few days (if v_{esc} / v_{rms} is around 1), or maybe a few years. In fact, for the majority of the gas to be retained by the planet for several billion years, we need v_{esc} / v_{rms} around 10 or more.
It turns out that v_{esc} / v_{rms} for Mars for most gases is too low. Water, ammonia, and methane, as well as helium and hydrogen are too light to be retained for long. (Although it turns out that water is just a bit too light, so it might stick around for thousands or millions or years.) However, it does appear oxygen, nitrogen, and carbon dioxide might be just heavy enough to be retained.
This means that if there had ever been a significant amount of liquid water on Mars, it would not have stuck around long. CO2, and O2, on the other hand, have a shot. (So I guess we could design a breathable atmosphere, but water would be a problem.)
Interestingly enough, these figures change (for the worse) if temperature increases on Mars (increases the kinetic energy of the gases), so making Mars more hospitable, temperature-wise, may make it less long-term hospitable, desirable molecule-wise.
I got a lot of this info from my undergrad astronomy/astrophysics text: Introductory Astronomy and Astrophysics, 4th ed, by Zeilik and Gregory. -- Paul
OpenSource.MathCancer.org: open source comp bio
Here are some thing wrong with this story, and the way /. handled it:
/. called it, or even a proposal by the scientists involved. It's a study; no one is proposing to terraform Mars.
1. The notion of terraforming Mars isn't exactly new.
2. This short and incomplete report would be comfortable in a tabloid, not in the broadsheet Guardian, a left-wing UK paper funded by a left-wing UK foundation to promote left-wing ideology. (Nothing wrong with being left-wing, or right-wing, but it helps to know who's paying for the news you're reading.)
3. This is not a NASA proposal, as
-- Slashdot: When Public Access TV Says "No"
My guess is you're conservative because you'd rather save $5 today than avoid a possible global crisis. The narrow minded, poor planning, ethnocentric, pathetic administration is right up your alley.
Sorry, but that pre-judgmental, unsubstantiated, conversationally shallow, narrow-minded, and just dead wrong comment, meant to do no more than enflame a meaningless confrontation... warrrants no further reponse than this.
4 out of 3 people have trouble with fractions
While I think you're off base on the global warming thing, there is a point in there that I think people ignore.
Humans can, with a little enthusiasm, make the planet uninhabitable for themselves, via nuclear winter, global warming, etc, etc. However, making it uninhabitable for people and killing all life on the planet are two very different things. Even if we drastically change the environment, there are plenty of extremophilic life-forms that will simply expand out of their current niche, mutate, and re-fill the planet with life. Cockroaches, bacteria living near volcanic ocean floor vents... Life in general is resilient. You're probably not going to sterilize the planet, at worst you'll make it unlivable for people.
To truly understand recursion, you must first truly understand recursion.
I am starting the People Unified to Stop Science In Extraterrestrial Settings. Join today to help us stop this senseless disregard for possible microbial life on Mars! Life is life and we must preserve it to the end!
We can make Mars like Earth when we're done making Earth like Venus.
Let's try to focus here, people.
Coming soon - pyrogyra
We found it. It didn't have anyone's name on it.
"Flyin' in just a sweet place,
Never been known to fail..."
In other news, shares of automakers flew through the roof today as speculators pointed to the need for tens of millions of automobiles that will need to be left idling for a week to trigger this. Contruction on the 6-lane highway that the cars will be parked on has begun this week, complete with toll booths and signs for Jersey City exits.
Scientists are positive that the past 100 years of atmospheric modeling on US roads has produced the most effective greenhouse booster possible.
"Beware of he who would deny you access to information, for in his heart, he dreams himself your master."
For an entertaining discussion of methods of terraforming Mars and the politics that go with them, see Red Mars (1992), Green Mars (1993) and Blue Mars (1996) Kim Stanley Robinson, which scored a Nebula and two Hugos.
"We reject as false the choice between our safety and our ideals." --The American President (20.1.2009)
I've been reading something over at space.com today that's a panel discussion regarding terraforming Mars. Topics include could we, can we and should we?
The Spoon
Updated 6/28/2011
I don't think mars has enough gravity to hold molecular oxygen.
On a related note, the Earth doesn't have the gravity to hold Hydrogen or Helium. I've always imagined that the stuff probably boils off at a rate that varies with the amount of water in the upper atmosphere.
And there seems to be a good amount of water entering due to mini comets (see Dr. Frankl's mini comet theory, which received support a few years back from some NASA studies. We may be constantly getting new water added, mostly to our upper atmosphere.) If some of this water were broken apart, with the Hydrogen escaping and the oxygen remaining, this would be another argument in favor of early earth having an oxidizing atmosphere, an issue currently under some debate.
BTW, does anyone know if there any planets that actually have been confirmed to have a reducing atmosphere? Does Venus?
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It's the end of my comment as I know it and I feel fine.
You're seriously scaring me.
But here's somthing I've never quite understood. I can understand how eutrophic ponds become anoxic when you have a sudden die-off and decomposition. But with the ocean, the surface should remain oxygenated (since it has living plantlife) but the depths would be anoxic. You can only suck so much oxygen from the water. Not all the plantlife would decay since you can only take so much oxygen out of the water and most of the organic matter would be buried under sediment.
The surface and depths should be separated by several thermoclines so the water won't mix like it would in a lake.
And oceans don't 'turn over' the same way that lakes do (though they do cycle, but that happens slowly over several centuries). So would an algal bloom really cause anoxyic conditions in water that was several miles deep the same way that it would in a shallow pond?
___
It's the end of my comment as I know it and I feel fine.
Ill admit, I didnt RTFA. But the general thing Im reading here is based on an AWEFUL lot of assumptions, most of which arent true.
Terraforming another plante, sounds good on paper. But can we please pick a planet that is shielded from the solar wind so all the 'efforts' arent wasted away, or in this case blown away into outer space.
Without an active magnetic field, the upper atmosphere of mars would be directly exposed to solar flares, radiation storms, etc. Which is why there is no atmosphere there now. Nothing to do with water on the surface, it just sublimates and gets ejected off the planet anyway if there was water.
So until someone figures out a way to start a regenerating dynamo half the size of the planet mars INSIDE the planet mars, can we stop with the mental masturbation?
Well, as we've fucked up the Earth already, we'd better start terraforming Mars ASAP. If we're content to render hundreds of Earth species extinct, I don't see it makes sense to be precious about a few Martian bacteria.
That was classic intercourse!
We, humans, are the first species on Earth capable of spreading our biosphere into space. It is not alarmist to say that continent and planet cleansing events happen on a periodic basis. The recent tsunami and asteroid 2004MN's ever-changing error ellipse are evidence of dynamic, destructive processes that affect both humanity and the larger biosphere. It is our duty, as the first space-goers, to create bio-redundancy, to explore and develop.
A project as large as terraforming Mars (or an asteroid) by it's very nature will require massive biological systems for completion. I predict that living creatures will be adapted both to vaccuum and various atmospheres, if we don't find life already there - giant tree cities on comets, kelp ponds in Mars craters, post-human cyborgs, etc.
Creating new biospheres and offworld industries will greatly improve both standards of living and our ecological footprint on Earth. Enough colonization will mean the ability to protect the home world better. Making Mars bloom is our duty and destiny.
Support private spaceflight, it's the only way this can happen. And fire up the florine pumps. 8)
Josh
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The article states everything needed is available ON MARS. You'd send robotic factories to Mars to mine, process, and distribute the materials automatically. Nothing but the originial equipment would need to be sent. No chemicals would need be made here. No human interaction, except for some remote input, would be required.
If you screw up and make Mars atmosphere unsuitable for life... well, damn, it already *is*, so what have you lost?
The asteroid belt has a mass of about 1/10 earth. One alternative to dropping them directly on the surface, is that the asteroids could be accreted into a moon, perhaps using one of the existing moons as a starting point, or joining the existing moons together (by manipulating the velocities of the asteroids. The merged moons, plus asteroidal mass would form a large moon. Lunar tidal effects would heat the planet just as the lunar tides on earth cause friction and release some kinetic energy.
This kinetic heating would be a slower effect, but would not have the "instant heat and violence" of just hitting Mt. Olympus with the rocks. Of course the difficulty level is still pegged at "essentially impossible".
One approach to get this asteroid-pinball started would be to attach solar sails to asteroids -- a small CPU should be enough to control the sails to "brake" the asteroids and spiral their orbit toward mars. (But it would still take an enormous amount of time.)
The results could also be split - use some asteroids to hammer the surface (for heat and to release gasses) and others for moon building.
Launch a fresnel lens the size of Australia at the sun adjustable to keep its focus on the red planet. then videotape all the little green guys as they crawl out of the ground with their heads on fire.
...its easy to do when you've been testing it on your own planet.
-- Game Developers: Stop porting badly-textured games from crappy console systems!
This is all top-of-the-head stuff, but I remember reading once that a planet's escape velocity should exceed the RMS velocity of a gas by about six to retain that gas at that temperature. Mars's escape velocity is about 5 kms-1, and the RMS velocity of O2 molecules at room temperature according to this website is about 500 ms-1. No problem so far, but water molecules weigh just over half what oxygen molecules weigh, the RMS velocity of water vapour will be about sqrt(2) higher, putting it in the borderline bracket.
Since water evaporation takes a great deal of heat from liquid water, I imagine the continuous loss of water vapour from the Martian atmosphere would tend to cool the planet, reversing any terraforming effort, while leaching away the natural water resources which are thought to exist and which would be necessary to sustain life in a terraformed settlement -- leaving Mars drier and more wintry than ever ...
... I'm pretty sure every single step of that argument is seriously flawed, but frankly I doubt we have enough energy to terraform Mars anyway.
love: @echo "Not war?"
For even more "meaty" information, check out this research paper by McKay and Marinova from 2001, titled "The Physics, Biology, and Environmental Ethics of Making Mars Habitable".
Unfortunately, I don't think Marinova's latest paper on this is publically available on the internet.