Greenhouse effect could make Mars livable

[DRoseDARs]

Personally, I like the Stellar Jupiter project: Converting Jupiter into a star to make its moons more habitable. Talk about an arrogant vanity project...

[Kuciwalker]

Originally posted by DRoseDARs
Then why'd you ask,"With what?"

I thought you were talking about using an organic process to free CO2.

I can't answer that. Comets are relatively small compared to a planet - even as small as Mars - and we'd need LOTS of them for them to play a significant role in any terraforming project.

That misses the point of my question - how would you get nitrogen from comets at all? Do they have nitrogen?

[The Mad Monk]

As far as talk about living on the surface of Mars, whether they realize it or not, people do so because of that planet's terraforming prospects. People hate the idea of living underground and domes aren't a whole lot better.

People are adaptable, and those who are born on the new worlds will not miss the old one.

I remember a quote from Andromeda where Rebeka 'Beka' Valentine (the pilot), a spacer brat who grew up on starships said (something like) "How can anyone want to live on a planet? It's wet, it's dirty, there's no environmental controls, and how the hell can you sleep knowing there's no ceiling?"

I think that says it all, really.

[Kuciwalker]

Smashing them at Mars.

See above.

[Ned]

Originally posted by Kuciwalker


I thought you were talking about using an organic process to free CO2.



That misses the point of my question - how would you get nitrogen from comets at all? Do they have nitrogen?

Yes.

And, you could mine "comets" from the Kuiper belt.

[Geronimo]

Originally posted by DRoseDARs
As far as subsurface habitation on Mars, it is the safest way to colonize the planet given its lack of a substantial atmosphere (very low air pressure means great stress on any dome; thin atmosphere doesn't burn up incoming material such as meteorites).

I'm puzzled by why pressure domes are regarded as so impractical. Why would that apply to colonising places like mars but not to space stations?

[Geronimo]

Originally posted by DRoseDARs
Personally, I like the Stellar Jupiter project: Converting Jupiter into a star to make its moons more habitable. Talk about an arrogant vanity project...

*if* a nuclear reaction were somehow triggered in jupiters core, the pressure would expand the planet until it's reduction in density dropped the core temperature and pressure to below that which is needed to sustain fusion. There is a very good reason why brown dwarfs are all brown despite some extremely hot starts when they have a rapid formation.

[Geronimo]

Originally posted by Dr Strangelove
I hate to burst everyone's bubble, but in addition to supplying enough Oxygen gas to breath and warming the atmopsphere with some sort of "greenhouse gas" there also has to be a generous amount of inert gas, such as Nitrogen, in the atmosphere. If the atmosphere is more than 30% oxygen spontaneous combustion will occur. If the CO2 concentration is too high humans and other animals will be unable to blow off the normal amount of CO2 via respiration. CO2 will build up in their blood and they will die of acidosis. An enormous amount of inert gas is therefore required to dilute the oxygen and the greenhouse gas.

it's not the percentage of oxygen that is important but rather the absolute partial pressure of the oxygen, ditto for toxic effects of CO2.

[DRoseDARs]

Originally posted by Geronimo
I'm puzzled by why pressure domes are regarded as so impractical. Why would that apply to colonising places like mars but not to space stations?

Why does the ISS, Mir, or Skylab have such small windows? Why does the Space Shuttle and other craft? Why do airliners? Windows are a weak point in any environment where we need a pressurized cavity to survive. A dome will have lots of windows, if not entirely window with frame. In Mars' low gravity, solid windows (as opposed to inflatible structures some groups have proposed) might be good since they'll resist both the internal pressure and the windstorms of the planets (I'm thinking of the dust, not the force of the Martian wind). However, I'd be more concerned about falling material that survived the fall through Mars' thin atmosphere as well as solar radiation. Exposed structures are just that: Exposed.

More directly answer your question, domed structures would survive better in an environment where there was at least some outside air pressure, even if it isn't up to Earth standard, to counteract the internal air pressure and relieving some of the stress on the material used. Space is a relative vacuum; not external air pressure, the material bares the full brunt of the contained atmospheric pressure.

[DRoseDARs]

Originally posted by Geronimo


*if* a nuclear reaction were somehow triggered in jupiters core, the pressure would expand the planet until it's reduction in density dropped the core temperature and pressure to below that which is needed to sustain fusion. There is a very good reason why brown dwarfs are all brown despite some extremely hot starts when they have a rapid formation.

Sorry, I must've forgotten to add the smiley earlier...

[DRoseDARs]

Originally posted by Kuciwalker


I thought you were talking about using an organic process to free CO2.

I don't recall if I was, I doubt it and am too lazy at the moment to look, but I'll go ahead and respond. I have my doubts of how effective GM'd life would be in the early stages of a Martian terraforming process. I think what I was talking about earlier was using industrial processes to heat the planet by pumping CO2 into the atmosphere to make the environment more plant-friendly and perhaps start adding oxygen to allow for GM'd insects). I know squat about nitrogen, so I'm not the person to ask. In later stages, if GM'd plant and animal life (those CO2-tolerant insects) has taken root, the plants would slowly begin increasing the oxygen levels on their own if we let them, just as what happened here on Earth. For me it's all about the timing. I just don't think natural processes (bacteria, algae, lichen and so forth) can play that big of a role early on in such a project, not in Human time-scales at least.

That misses the point of my question - how would you get nitrogen from comets at all? Do they have nitrogen?

Again, I'm not the person to ask.

[Dr Strangelove]

Originally posted by Geronimo


it's not the percentage of oxygen that is important but rather the absolute partial pressure of the oxygen, ditto for toxic effects of CO2.

Yes, and that is also true for breathing. The Oxygen pressure we're used to is only 66% of the pressure at which spontaneous combustion of some materials occurs. Furthermore a pure oxygen atmosphere damages the lungs and eyes. Patients on pure oxygen begin to develop problems with their lungs even within 24 hours.

I wonder what sort of atmospheric pressure Mars is capable of sustaining?

With regards to ionizing radiation, Mars is 1.5 times further from the sun than we are, so I would assume that the intensity of radiation striking Mars' surface would be 40% of that being asorbed by the Van Allen blet or by the Earth. Does anyone know how efficient the Van Allen belt is?

[Urban Ranger]

Originally posted by Geronimo
I'm puzzled by why pressure domes are regarded as so impractical. Why would that apply to colonising places like mars but not to space stations?

Space stations are small so they don't have a lot of gravatational pull. It's highly unlikely anything big is going to smash them at high speeds.

Planets are different. They bring down small floating objects from space and they come crashing at a nice, high speed.

[Urban Ranger]

Originally posted by The Mad Monk
We'll be doing that with Luna, Mercury, Titan, probably most of the other major moons, and orbitals as well.

Why make a special case for Mars?

The cost of doing that is prohibitive, both in terms of energy and monetary.

That's why Mars is good and Luna is bad for any large scale permanent settlement.

[Wycoff]

Originally posted by The Mad Monk
Colonizing space is not a matter of economics to me, it is a matter of survival. Evolution has clearly demonstrated that the more a species expands, whether geographically, or in terms of habitat or food source, the longer it survives in this universe.

We thrive because we have managed to exploit nearly every crack and crevice this planet has to offer. We are immune to most catastrophes this world has to offer, because there is little here now that could hit every region, and every food supply.

Still, there are still threats out there, that can kill us off on a planetary scale.

The only real long-term countermeasure for this is the same one that has served us so well for so long.

Expand into new territories, or as in this case, new worlds.

My thoughts on this exactly. We need to look at long term survival. Colonizing Mars would be a good first step, providing us with valuable terraforming experience... we just need to make sure we don't destroy ourselves in the meantime.