Friday, December 19, 2003

The Beagle Has Landed...

Actually, the Beagle 2 probe from Europe is supposed to land, on Mars, on Christmas day. "The mission is the first to try to determine if there is life on Mars since the United States sent the Viking I landing craft to Mars’ surface in 1976. “It’s not looking for little green men, but it is looking for matter that might provide evidence of life. It is looking for clues,”" The first since 1976? What about the Mars Rover mission back in 1997? Mars is really a lousy place to look for life or, rather, signs of extinct life. As more data is amassed it is becoming quite evident that it did not have conditions favorable for origin of life scenarios. So... why send probes there looking for it? There are only two high-potential location candidates for life in our Solar System, apart from Earth. Mars, and a moon circling Saturn named Europa. Why? Mars is considered an approximation of Earth, at least in its early stages - which, again, is now being challenged. Europa has frozen water and potentially has liquid water underneath thick layers of ice. The reason for the flurry of activity surrounding Mars now - the U.S. has two probes scheduled to land in January - is that it is very close to Earth. Remember the news this summer about Mars' closest approach to Earth in thousands of years? Keep in mind over the next few weeks, and beyond, that there are scientists who are predicting that evidence of life will be found on Mars - but that it will be life that originated on Earth. The reason for this is that early in the Solar System's history there was a period of massive meteor impacts on the inner planets. There were impacts large enough to send debris back into space. Microbial life forms, or their remains, could have been on this debris and, eventually, some of this debris would find its way to Mars - entering its atmosphere as a meteor. Hugh Ross, at Reasons to Believe, has done a good job of letting his former Cal Tech colleagues know about the possibility of actually finding remains of Earth life on Mars. The good news is that they're listening to him.

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