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| | Mars |
 | | While the average temperature on Mars is about 218 K (-55 C, -67 F), Martian surface temperatures range widely from as little as 140 K (-133 C, -207 F) at the winter pole to almost 300 K (27 C, 80 F) on the day side during summer. |
 | | Much of the Martian surface is very old and cratered, but there are also much younger rift valleys, ridges, hills and plains. |
 | | The authors further suggest that these compounds, in conjunction with a number of other mineralogical features observed in the rock, may be evidence of ancient Martian microorganisms. |
| dept.physics.upenn.edu /nineplanets/mars.html (2044 words) |
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