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Deinococcus radiodurans

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Stressed parent
49119.  Thu Feb 02, 2006 4:40 pm Reply with quote

This is a tough scary bug - give this bug a dose of 5000gy of radiation and it survives (10 will kill a human) It can survive heat, cold, vacuum, and acid.


Quote:
Deinococcus radiodurans beats most of the constraints for survival of life on Mars - radiation, cold, vacuum, dormancy, oxidative damage, and other factors," said Dr. Robert Richmond, a research biologist at NASA's Marshall Space Flight Center. With other scientists, he is investigating the possible utility of extremophiles to serve human exploration to inhospitable locations

Source :http://science.nasa.gov/newhome/headlines/ast14dec99_1.htm

Its entry in wikipedia: http://en.wikipedia.org/wiki/Deinococcus_radiodurans

 
Celebaelin
49127.  Thu Feb 02, 2006 5:59 pm Reply with quote

*dreams*
The first thing you'd want is a photosynthetic organism. Cyanobacteria (blue-green algae) are often suggested as likely candidates for this as they are also nitrogen fixing. On Mars however we won't be looking at "terraforming" to a state where the surface is freely habitable. Whilst I think I've heard that the planet could be warmed so that the water would become liquid, the vapour portion (ie eventually virtually all of it because of the liquid/vapour equilibrium) would then be lost because of the low g.

Life support considerations are paramount, they are in effect the primary concern in determining whether a course of action is feasable either on a new planet or in travelling to one. Mars cannot hold an earth-like atmosphere as its gravity (0.38g) is too low so we're talking about enclosed areas, probably geodesic domes, and we're having trouble establishing that we can seal these off adequately ie avoid leaks - if ants can get in, as they have, gases can too. In the case of Mars more critically it means they can leak out. Seals can never be perfect but I'd like to think in working out Life Support calculations that the seals were going to hold anything the size of diatomic nitrogen or larger very efficiently. Hydrogen is not a Life Support consideration per se (except in its power provision implications) but there shouldn't be much free in the breathable fraction anyway - pipe it basically. In order to be able to deduce the life support demands we really want to have experimental data rather than to be obliged to work from conjecture of eg BOD (Biological Oxygen Demand) over long periods.
Quote:
The martian atmosphere is only 7mbars thick, which is not very much compared to Earths' 1000mbar atmosphere. But this atmosphere is thick enough to prevent the deadly solar storms from reaching the surface of the planet. Because Mars' gravity is about 1/3 as strong as Earth's, the 7mbar atmosphere would be a 21mbar atmosphere on Earth.

http://www.geocities.com/marsterraforming/current.html

(Warning: This article contains errors eg germinating plants experience geotropism, also called gravitotropism, the direction of growth being dictated by the direction of the action of gravity, and presumably the strength.)
http://www.biologie.uni-hamburg.de/b-online/e32/32c.htm

"Conan the Bacterium" (LOL) could have its uses obviously but the suggestions, and potential consequences, of deliberate widescale release into the Martian environment don't to me seem to have been adequately evaluated. It could so easily become an uncontrollable disaster as eg Deinococcus radiodurans out-competes either any long-dormant/currently extant native life-forms or any other bacterial strain that we might wish/need to grow externally to the habitation areas.

 

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