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Mars Terraforming Debate
blackhelicopter writes "This Guardian article describes the implications of terraforming Mars - the subject of NASA's forthcoming debate. Quote from Dr Lisa Pratt, a Nasa astrobiologist, concerning life probably already on Mars: 'We simply cannot risk starting a global experiment that would wipe out the precious sensitive evidence we are seeking'."
The issue of terraforming has been argued extensively in science fiction for years. The most notable books on the topic are by Kim Stanley Robinson, author of Red Mars, Blue Mars, and Green Mars (a hard-sci-fi trilogy on the terraforming of Mars and its consequences).
I wouldn't be too much worried... we just need to provide around 10^19 kg of nitrogen (or some inert gas) and 0.3 x 10^19 kg of oxygen.
r sfact.html)
These are absolutely huge numbers. Even if we take all oxygen from all our water from the Earth this won't be enough to fill out the Mars atmosphere...
BTW, some facts about Martian Atmosphere (from http://nssdc.gsfc.nasa.gov/planetary/factsheet/ma
Surface pressure: 6.36 mb at mean radius (variable from 4.0 to 8.7 mb depending on season)
[6.9 mb to 9 mb (Viking 1 Lander site)]
Surface density: ~0.020 kg/m3
Scale height: 11.1 km
Total mass of atmosphere: ~2.5 x 10^16 kg
Average temperature: ~210 K (-63 C)
Diurnal temperature range: 184 K to 242 K (-89 to -31 C) (Viking 1 Lander site)
Wind speeds: 2-7 m/s (summer), 5-10 m/s (fall), 17-30 m/s (dust storm) (Viking Lander sites)
Mean molecular weight: 43.34 g/mole
Atmospheric composition (by volume):
Major : Carbon Dioxide (CO2) - 95.32% ; Nitrogen (N2) - 2.7%
Argon (Ar) - 1.6%; Oxygen (O2) - 0.13%; Carbon Monoxide (CO) - 0.08%
Minor (ppm): Water (H2O) - 210; Nitrogen Oxide (NO) - 100; Neon (Ne) - 2.5;
Hydrogen-Deuterium-Oxygen (HDO) - 0.85; Krypton (Kr) - 0.3;
Xenon (Xe) - 0.08
Don't try to use the force. Do or do not, there is no try.
Aren't we going to terraform Mars or Venus?
Terraforming is a long-term project requiring technology significantly advanced over what we have today. Even terraforming advocates admit it would take a minimum of 200 years to modify Mars to the stage where even simple anaerobic microorganisms and algae can survive. [Ref: Terraforming: Engineering Planetary Environments, Martyn J. Fogg, SAE Press 1995.] Space habitats, on the other hand, can be built with today's technology, and would be homes in space which people initiating the program could move into within their lifetimes.
Interstellar travel may someday become possible, but we have no guarantee that Earth-like planets will be as plentiful in the Milky Way galaxy as they have been in Hollywood, CA.
What advantages would orbital settlements have over a colony built on another planet?
Sunlight also drives the life-support system of the habitat, so the day/night cycle can be set to whatever is convenient. Compare this to the moon, where there is 14 days of continuous daylight, and then a 14-day-long night. Here, some alternate energy source would probably have to be used half the time.
Zero G would be a liability if there were no alternative to it. Astronauts experience loss of bone mass and muscle tone after prolonged exposure to weightlessness. But most of a space habitat would be under Earth-normal gravity, although there would be easy access to regions of reduced gravity and zero G (perhaps for personal flight). With planets, on the other hand, you have to take the gravity that's there, and it's often the wrong kind of gravity to keep us healthy. Lunarians or Martians would probably not be able to visit the Earth (nor accelerate at 1 G).
Seastead this.
That's millions of generations for bacteria.
See the problem here? These are religiously inspired buildings.
Very true. I did a Google search for various time lengths (five/ten/twenty year plan). Anything less than ten years was commercial/industrial, ten to thirty years was regional government, and anything over thirty years was religious/fanatical.
I don't think that's quite accurate. Volcanos can emit quite a bit of HCl and sulfate aerosols. The latter tend to amplify the effects of human-generated CFCs. Check out this link
The US has tried to be careful about sterilizing its Mars landers. The Viking landers were very thoroughly sterilized, since their main purpose was to look for signs of life; it was important to eliminate false positive results from terrestrial "hitchhikers". The Pathfinder and MER landers were mainly geology missions and that, combined with the negative Viking results, led to a somewhat lower standard of sterility. (IIRC they went over the exterior of the rover with disinfectants, but did not have to heat sterilize all the internal components.) According to this interview:
http://www.ksc.nasa.gov/nasadirect/elv/merb/theis- ab.htm
"There is a set of international treaties and agreements that regulate the ability of us to take bacteria or organic material or spores to Mars in order to avoid contaminating Mars for future scientific investigations. The Mars Exploration Rover project is what is called a Class B. We're not involved in the search for life and so we have a level of cleanliness that we did when we put the rovers together. If you were a Class A mission looking more directly for life, the requirements would be much more stringent. You would actually have to sterilize the equipment, almost like an operating room, in order to be able to satisfy these agreements."
I'm curious about the extent to which the Soviet Mars landers were sterilized. None of them were exactly successful, but a couple made it to the surface and crashed there.
Despite this being /. I decided to perform a bit of research, so here are a few links to pages that I think support my point, that terraforming as far as a more hospitable atmosphere on Mars is possible:
They may be wrong, I may be wrong, but simply claiming the fact that the current Martian atmosphere is very thin as proof that no sustainable atmosphere is possible on Mars, that does not cut it. I will grant you that a 99% earth-like biosphere is unlikely, but a lot less is needed for it to be of use to a colony. Even a slight increase in temperature and pressure would make it easier to live on Mars, some plants might be able to grow (genetically modified mountain plants), the domes (or whatever it might be) needed for habitation might have to handle a smaller difference in pressure, or the time an astronaut might survive in an accident might increase.
And besides, even if it only lasts a few thousand years, an atmosphere might still prove useful. Not that I think we should do something like this without considering the consequenses, but once we have the technology, the trade-offs and risks might prove to be small enough for us to attempt terraforming Mars.