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Hardy lichen shown to survive in space 17:16 10 November 2005 NewScientist.com news service Kelly Young
Enlarge image Lichen is actually two types of creature, rolled into one – the algae provides the fungi with food while the fungi offer the algae a cosy living environment (Image: L Sancho)Lichens can survive unprotected in the harsh conditions of space, a European Space Agency experiment discovers.
The organisms are a composite of algae and fungi. They are commonly found on the surface of rocks on Earth and can survive in extreme conditions such as high mountains latitudes. Lichens are the most complex form of life now known to have survived prolonged exposure to space.
In an experiment led by Leopoldo Sancho from the Complutense University of Madrid, two species of lichen – Rhizocarpon geographicum and Xanthoria elegans – were sealed in a capsule and launched on a Russian Soyuz rocket on 31 May 2005.
Once in Earth orbit, the lid of the container opened and the samples were exposed to the space environment for nearly 15 days before the lid resealed and the capsule returned to Earth.
The lichens were subjected to the vacuum of space and to temperatures ranging from -20°C on the night side of the Earth, to 20°C on the sunlit side. They were also exposed to glaring ultraviolet radiation of the Sun.
“To our big surprise, everything went fine after the flight,” says Rene Demets, ESA’s project scientist for the Foton project. “The lichens were in exactly the same shape as before flight.”
Hitching a ride In space, the lichens turned dormant and did not metabolize, but once returned to Earth, they returned to their normal activity and their DNA appeared not to have been damaged, Demets told New Scientist. All of the lichen appeared to endure the ultraviolet radiation, even those receiving the most exposure.
Lichens have a tough mineral coating that could shield them from UV rays. They are also made from individual organisms layered on top of one another, so outer layers may provide protection for underlying cells. The organisms have already been shown to be capable of withstand high levels of UV radiation on Earth.
The experiment adds weight to the theory of panspermia – that life could somehow be transported between planets, perhaps by hitching a ride on an asteroid. It also indicates that organisms similar to lichens might be able to survive on the surface of Mars – at least during the planet's summer.
Symbiotic relationship Although the Martian atmosphere is very thin, it is filled with carbon dioxide, which is necessary for lichens’ photosynthesis. The lichens might not survive on Mars for long, however, because of low oxygen levels in the atmosphere.
In the 1980s, experiments carried out on NASA’s Long Duration Exposure Facility satellite showed that certain bacteria are hardy enough to endure space. Rocco Mancinelli, a microbial ecologist with the SETI Institute in California, who has also done experiments with micro-organisms in space, says he is not surprised to see lichens survive outside the Earth's atmosphere.
The algae and fungi that make up lichens exist in a symbiotic relationship. The algae provide the fungi with food while the fungi offer the algae a cozy living environment.
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I would think that anything that survived atmospheric entry via asteroid would have to of been centrally located in the asteroid. No way anything organic could survive that amount of heat and friction.
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Space water discoveries enhance odds for early life Zag A cross-section of the Zag meteorite
September 8, 1999 Web posted at: 5:18 p.m. EDT (2118 GMT)
By Robin Lloyd CNN Interactive Senior Writer
(CNN) -- Back to back discoveries of water trapped in one meteorite and likely water in a second suggest that the liquid of life was far more abundant in the early solar system than previously thought, scientists say.
NASA researchers have cracked open two meteorites in recent months and definitively found in one -- and possibly found in a second -- tiny pockets of briny liquid water from deep space.
In space, that water was probably unleashed during a warming event that lasted 10 million to 20 million years and could have freed up enough of it to shape rocks on planets and start up organic reactions necessary for life, said Michael Zolensky, a space scientist at NASA's Johnson Space Center.
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just a matter of time before we find some form of inter stellar life. No doubt it will not be a little green man but rather a little green slime.
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I have never seen any compelling evidence or even a reasonable probability that life was brought to Earth from "outside". Clearly the notion develops a feasible mechanism, but no where near the feasibility that life spontaneously generateed within the conditions of one or more of Earth's early states. Somehow, I see the same basic argumnent for life having come via comet or meteor and in the notion of "creation science; that is, that life is too intricate and complicatede for it to have come about on it's own.
People for whom the twist and turns of mathematics, chemistry, and physics is bemusing or insurmountable should have better sense and manners than to insist that others, not so restricted, be tied to their limitations.
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So you are saying that anyone who thinks life could be transfered from interstellar body to body is a moron because they are not equipped with your specific talent when it comes to thinking?
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