Jex said: There's water on Mars; since we have telescopes people have looked at it on Mar's poles. Go look at some pics, fer crying out loud!

Um, the "ice" on Mars is a thick candy shell of dry ice, with a little water ice below it. At the most, it's 50/50, but drilling to get it would be problematic.

Oh, and Baba - we have moonquakes as well, but that doesn't mean there's "tectonic" activity on the moon. Mars is essentially a dead rock and can only support human civilization fractionally better than the moon could.

It might actually be easier to terraform Venus, except for the fact that if you precipitate out all the carbon in its massive CO2 atmosphere, you'd end up with something like a half-mile deep of carbon soot over the entire surface.

Perhaps we should just terraform Titan, Europa, or Encleadus instead. Might be easier.

Lexicon, the only problem with that is that we're not allowed near Europa. We get all of the rest of Jupiter's moons, but Europa's off-limits. Don't you ever watch movies? I'm all for Enceladas, though, they're delicious.

baba: you're right about the water and Mars's atmosphere as far as I can tell. A meteor strike will not, however, kick-start the tectonics again; to do that you'd need to reignite the heat source within the planet, and that's too cool. You may trigger a quake/eruption or two where tension has been building, but that's all. What we need to do is drill to Mars's core, and build a giant nuclear reactor, that'll do the trick!

Talk of terraforming reminds me of articles I've read from the 70s, when we were afraid of Global Cooling (didn't pan out, now the political scare is Global Warming), there was actually talk of putting soot on Earth's poles, to absorb more heat. I read an article a month ago suggesting simulating the temporary cooling effect of a major volcanic eruption by deliberately pumping sulphur dioxide into the atmosphere to produce aerosols to increase the albedo of the Earth and cool it artificially. Imagine if we did that, then Earth went into another natural cooling cycle like the one in the 40s-60s that spawned the cooling scare (which was followed by the current natural warming cycle which may have ended in '98); we'd have another "Little Ice Age." It would be interesting to see what we can learn about Earth and planetary systems in general by terraforming Mars.

@Lexicon: Not talking about quakes... talking about the photograph of an active fault line... with water spilling out. And, it's generally easier to add materials then take 'em away Lexicon... Mars is a far easier terraforming project as I see it. (LOL, easier terraforming... we evil flying monkeys sure have gotten a bit big for our britches eh)

@Chaos: A large enough collision (preferably of some highly radioactive material... Xith roid?) would impart immense quantities of energy to the planet that would take millennia to dissipate. Why radioactive? The primary heat generator in the Earth is thought to be radioactive decay. So, no need to "build" a reactor, injecting enough radioactive material should do the trick. (Problem is, you don't really want it all over the surface.) Also, The rock would have to be HUGE and FAST. At the very least you would create an atmosphere... albeit a temporary, highly radioactive one, made up mostly of vaporized rock.

Hmm... chillum, your comment on where most of the heat on earth comes from is interesting. What do you base it on? Do you have numbers? If this comes off as a mlevolent critique, it isn't, I'm genuinely interested, since I thought that most of the high temperature we have on earth is the consequence of energy transmitted via light by the sun and the energy still intrinsic to earth, although she is cooling down, or so I thought. My knowledge about geophysics is limited at best.

I'll look it up, but that's what I thought the source was, too, which is why I joked about building a giant nuclear reactor inside Mars. Energy from the Sun is enough to keep the surface warm, but it doesn't penetrate (that's why it's cold in the ocean once you get deep, unless you're in a warm current). The energy driving plate tectonics is partly leftover heat from planet formation, and mostly radioactive decay from the core.

EDIT: I first learned about the radioactive decay in a geology class, but this may be a good source for you, toshiro: http://www.pnas.org/cgi/content/full/201393998v1

Toshiro, recent studies suggest that a good portion of the heat in Earth's core is being generated by radioactive decay - as in, earth's core actually has a good bit of uranium in it... Here's a decent article on the subject: http://www.newscientist.com/article.ns?id=mg18725103.700

Bottom line is: Mars is only sleeping... Dare we wake him up? (God of War and all that...)

Yeah, except we've drawn on him with permanent marker and wrapped him in duct tape before we wake him!

Eh, Jex. I don't need you or Genka to be proud of me.

Because I know I troll better than both of you combined.

Anyway, I am rather disappointed in your choice of defense that I am simply using "semantics" on the satellite thing. I expected something more, umm, clever?

Back to more "serious" stuff here (nicely separated from my other jex-bashing post) :

Leebs : newscientist is the TABLOID of science. I approach their claims with a 10 foot pole.

Mars vs Moon : Mars is probably better at supporting human civilization for 2 reasons. (a) Atmosphere which keeps heat in and regulates the climate (b) gravity to keep the atmosphere.

Don't belittle (b), because if you pour H2O/O2/whatnot into the Moon's atmosphere, the Sun will heat it up so fast that the molecules will reach escape velocity and out-gas into space. You can compute how much "atmophere" left by assuming thermal equilibrium of the gas, and the boltzman distribution will tell you how much gas left will be stuck on the moon. The answer will be...you got it, exactly what's left on the moon right now (the moon has a thin atmosphere).

Also, here is a fun fact : energetically it takes less energy to fly to and then *land* on Mars than it is to do the same on the Moon. Extra credits for figuring out why.

I don't remember where I read about the Moon's atmosphere, but isn't it a very small number of sodium particles? I have no idea why it would be easier to land on Mars. A Moon colony is quite feasible, it would just have to be sheltered (underground might be best, but that's my own speculation).

It's easier to land on mars because it has an atmosphere that you can use to brake your ships. So you don't have to carry the extra gas needed to slow your ships down to achieve orbit/land etc. (Try the airbags trick on the Moon and you'll make a very big hole.)

Now I feel dumb. Of course you're right!

WWL said "newscientist is the TABLOID of science. I approach their claims with a 10 foot pole."
Yeah yeah, best I could google on short notice. Plenty of other journals, both "respected" and "non-" have raised the same theory.

OK fine, aerobraking makes slowing down easier on Mars. Still, fuel costs are less for a moon trip. Airbags would work just fine on the Moon as well, if you could slow your descent with rockets first...

Anyway, for the near future, any permanent colony on either Moon or Mars would need to be dug out, underground, sealed from the exterior, and then have the mother of all HVAC systems put in to maintain atmosphere and heat the place.

Granted, in 10,000 years, if we kept at it, we might get Mars close to "habitable" without always wearing suits and bringing your atmosphere with you. But, all that hard work would slowly evaporate, literally, since Mars can't keep an atmosphere similar to Earth's: No magnetic field, not enough mass/gravity. We'd need to constantly smash ice comets into the planet, or something, to continuously regenerate the atmosphere.

I'm a realist - there's no way that without first implementing enormous political, economic, and social change on THIS planet, that we'd be able to sustain even a hundred years of long-term terraforming on Mars. So, I say screw the terraforming, let's learn to live in sealed-off caves on another (closer) world first, before we get all crazy with the "Living on Mars" thing.

Well Lex, if that dastardly GW is ready to kick it into high gear as "they" say it is (global warming, what, you thought this was going to be another anti Bush tirade didn't you!), our collective hand may be forced one way or the other.

Ooh! A tangent! This thread is about to go off-topicer. Yes, it's a word, I made it up just now. We're going from good evidence of liquid water on Mars, to theories of terroforming/colonization, to not science at all, but the politics around the retarded "consensus" that doesn't exist on something that may or may not be happening and that we can't stand in the way of if it does! This is going to be fun....

Umm... global warming isn't happening? Riight.

Human influence (or, rather, its extent) is debatable, but not whether it exists or not. I agree with you that it doesn't really fit into this thread, though.

As for terraforming Mars: Utter nonsense, much like Lex put it. We do not have the circumstances needed (yet, I hope) to even think about undertaking such a project.

Of course terraforming is nonsense... this thread began in nonsense and will die nonsensically. Still fun to speculate on.

But then again: Never underestimate evil flying monkeys. (And especially: Never turn your back on em... they'll steal your camera in a heartbeat and make you "buy" it back with treats.)

@WE WANT LEEBS!: Were you just dissing newscientist.com? Or do you actually think that radioactive heating is BS? If the latter, please give an alternate theory. It's pretty well accepted at this point that there is WAY to much heat for it to simply be leftover energy from the formation of the Earth... and tidal forces are not enough either (probably). There's some idea of a rapidly spinning iron core... possibly supplying enough frictional energy? (Course if the core is "rubbing" that much... it'd probably have spun down millennia ago. Which'd be bad... very bad, as it is possibly the generator for the protective magnetosphere...)

@Lexicon: Of course.... that's why we need to re-stoke the furnace. If we "wake" Mars it can support it's own (thin) atmosphere (theoretically). It'd be a good idea to load it up with water and other goodies in the early stages though since we won't want to be smashing anything into it after we've already colonized it.

Also, I think you're misunderstanding something (not sure what exactly, and for that matter you may be right on... IANAA*) about the magnetic field's role in atmospheric retention. "Solar winds" are not wind at all... just a way of describing the infinitesimal "push" of light and other subatomic particles streaming out from the sun. Hell, comets circle the sun for billions of years before all the gas and other material is ablated. And they are of course tiny in comparison to something like Mars. They are generally also moving much much faster and come much much closer to the sun. Course, in most cases they also spend most of their time much much further from the sun.

*I Am Not An Astrophysicist (hell, I'm not even a plain ol' run of the mill ordinary physicist (for that matter, I'm not even very well "educated," 99% self-taught (in everything, not just physics (home "educated" ... my parents gave me the three R's, the rest has been pretty much up to me))))

Lexicon : Heh. I actually think colonization of any kind/planets are ill-advised, at least for the moment. I won't even rant about the current plan for the moonshot...

CBB : I am dissing new scientist in general. no comment about the radioactive heating. It's a lot of speculation and there may be other explanations of earth temperature core.

Atmospheric retention is mostly gravity vs molecular velocities. Now there are plenty of mechanism to transfer energy from the sun to the molecules of your atmosphere; e.g. radiative transfer, mechanical transfer via direct particle collisions of cosmic rays etc etc. For most planets in our roughly benign sun, it's mostly radiative transfer I believe, since we get most of our energy from the sun via radiative transfer.