[X] My Assistant

[Guest_RGClark_*]

Lichen Survives In Space.
"Leopoldo Sancho from the Complutense University of Madrid, indicate that lichens have the capacity to resist full exposure to the harsh space conditions, especially high levels of UV radiation. Analysis post flight showed a full rate of survival and an unchanged ability for photosynthesis."
http://www.physorg.com/news8054.html

The algae in lichen rely on photosynthesis as plants do, therefore metabolize CO2. Therefore they might be able to survive as well on Mars. However, some photosynthetic organisms require oxygen as well. It's unclear if the species tested could survive in a largely CO2 atmosphere, though Mars does contain small amounts of oxygen in its atmosphere.

Gil Levin argued that some patches on rocks at the Viking landing sites gave the appearance of lichen:

Color and Feature Changes at
Mars Viking Lander Site.
J. Theor. Biol. (1978) 75, 381-390
http://mars.spherix.com/color/color.htm


Bob Clark

[edstrick]

We've recently had a fairly extensive discussion of Levin's paper and other information on another thread here. In summary, though he was one of the very first people to try to work with Viking Lander color data, his analysis was half-competetent by somebody who barely understood what he was doing and it's results have been used in support of inferences that they do not substantially support. The paper also was "shopped around" to several peer-reviewed journals and finally published in a minor journal who's reviewers probably didn't have a clue what they were reviewing.