The instrument, called Urey: Mars Organic and Oxidant Detector, has already shown its capabilities in one of the most barren climes on Earth, the Atacama Desert in Chile. The European Space Agency has chosen this tool from the United States as part of the science payload for the ExoMars rover planned for launch in 2013."The main objective of ExoMars is to search for life. Urey will be a key instrument for that because it is the one with the highest sensitivity for organic chemicals." Ehrenfreund, one of two deputy principal investigators for Urey, coordinates efforts of team members from five other European countries.
Urey can detect several types of organic molecules, such as amino acids, at concentrations as low as a few parts per trillion.
All life on Earth assembles chains of amino acids to make proteins. However, amino acids can be made either by a living organism or by non-biological means. This means it is possible that Mars has amino acids and other chemical precursors of life but has never had life. To distinguish between that situation and evidence for past or present life on Mars, the Urey instrument team will make use of the knowledge that most types of amino acids can exist in two different forms. One form is referred to as "left-handed" and the other as "right-handed." Just as the right hand on a human mirrors the left, these two forms of an amino acid mirror each other.
Amino acids from a non-biological source come in a roughly 50-50 mix of right-handed and left-handed forms. Life on Earth, from the simplest microbes to the largest plants and animals, makes and uses only left-handed amino acids, with rare exceptions. Comparable uniformity -- either all left or all right -- is expected in any extraterrestrial life using building blocks that have mirror-image versions because a mixture would complicate biochemistry.
"The Urey instrument will be able to distinguish between left-handed amino acids and right-handed ones," said Allen Farrington, Urey project manager at NASA's Jet Propulsion Laboratory, which will build the instrument to be sent to Mars.
If Urey were to find an even mix of the mirror-image molecules on Mars, that would suggest life as we know it never began there. All-left or all-right would be strong evidence that life now exists on Mars, with all-right dramatically implying an origin separate from Earth life. Something between 50-50 and uniformity could result if Martian life once existed, because amino acids created biologically gradually change toward an even mixture in the absence of life.:
2007-03-24 04:48:54
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answer #1
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answered by Hope Summer 6
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NO, life is PROBABLE. It is below the surface. That is the only place life can exist on mars.
2007-03-26 13:16:20
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answer #2
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answered by ruttster 3
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All Planets within our Solar System has Life on it in one form or another.
Where there is Light there is Life. The Sun shines on all the planets.
2007-03-24 11:41:44
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answer #3
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answered by Anonymous
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If you mean life as microscopic bacteria, then yes.
2007-03-24 12:04:38
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answer #4
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answered by Stan 2
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yep, did u hear bout pluto getting kicked out the solar system, they think it was actually a moon, not a planet.
2007-03-24 11:37:33
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answer #5
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answered by Anonymous
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Visit space.com for investigations. There are signs
2007-03-24 11:41:58
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answer #6
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answered by Dosage 3
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yes, according to some sources...
2007-03-24 11:43:58
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answer #7
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answered by Indiana Frenchman 7
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No - it is far too hot.
2007-03-24 11:37:34
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answer #8
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answered by celianne 6
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