[url=http://www.guardian.co.uk/science/2013/jun/19/mars-oxygen-rich-atmosphere]Article:[/url]
[quote]Mars had an oxygen-rich atmosphere more than a billion years before the Earth, say scientists. An examination of meteorites and rocks on the planet suggests that oxygen was affecting the Martian surface four billion years ago.
On Earth, oxygen did not build up to appreciable quantities in the atmosphere for at least another 1.5bn years.
The researchers compared Martian meteorites that have crashed onto the Earth with data from rocks examined by Nasa's Spirit Mars rover. Differences in their composition can best be explained by an abundance of oxygen early in Martian history.
Spirit was exploring an ancient part of Mars containing rocks more than 3.7bn years old. The rocks bear the hallmarks of early exposure to oxygen before being "recycled" – drawn into shallow regions of the planet's interior and then spewed out in volcanic eruptions.
Volcanic Martian meteorites, on the other hand, originate from deeper within the planet where they would be less affected by oxygen. The meteorites travel to Earth after being flung into space by massive eruptions or impacts.
The new research, published in the journal Nature, has implications for the possibility of past life on Mars. On early Earth, the atmosphere was gradually filled with free oxygen by photosynthesising microbes. Scientists call this the Great Oxygenation Event.
The link between oxygen and life on Mars is less certain. Oxygen could have been produced biologically, or by a chemical reaction in the atmosphere.
Lead scientist Professor Bernard Wood of Oxford University said: "The implication is that Mars had an oxygen-rich atmosphere at a time, about 4,000 million years ago, well before the rise of atmospheric oxygen on Earth around 2,500 million years ago.
"As oxidation is what gives Mars its distinctive colour, it is likely that the 'red planet' was wet, warm and rusty billions of years before Earth's atmosphere became oxygen-rich."[/quote]
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old news.
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Oxygen is actually an extremely poisonous gas due to it's high reactivity (it's a strong oxidant, go figure). The production of oxygen by primitive plants caused a mass extinction on Earth - however it does also allow for sustained energy release in oxidation reactions, which is conducive to life. Oxygen isn't a necessary prerequisite for microbial life, but it is useful for eukaryrotes (sp?) and the like.
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Can't wait for the day we go to Mars. Looks like the astronauts got some planning to do for walking on Mars. Gotta come up with an epic phrase like Neil did!
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Edited by BADMAGIK: 6/21/2013 3:41:30 PMWhat if our real home planet was Mars and our species was going to be extinct along with the rest of the planet because of the natural order of things. We saw potential with Earth, but knew we could not live here because of the original inhabitants of this planet, the dinosaurs. So what we did was grab an asteroid and sent it on it's way to Earth to wipe out the rest of the dinosaurs so that one day in the future, our species would rise again.
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that robot is really in a desert
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We need a manned mission to start excavating Mars
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Reapers.
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Yes and then it left because the escape velocity was lower with Mars having less mass and therefore gravitational attraction so the molecules eventually left the atmosphere leaving the planet as barren as ever meaning only Earth would have it.
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Is Oxygen the only requirement for having a livable atmosphere?
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Further strengthening my theory that earth based life came from Mars.
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Everyone remember to thank the Earth's core for still being active when they go to bed tonight.
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Good job, you figured out what the rest of us have always known.
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Yay for Mars but Saturn is better.
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:) Looking forward to gettin' dat red dirt on my boot.