The Dread Planet (Life on Mars?) - Boston Globe

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The dread planet

Why finding fossils on Mars would be extremely bad news for humanity

By Nick Bostrom
May 25, 2008

THE IDEA OF life on Mars has been with us for nearly 300 years, ever since early astronomers saw what they believed to be polar icecaps through their primitive telescopes. If NASA's Phoenix lander successfully touches down on Mars this afternoon, it will become part of a long experiment to determine whether the planet was ever habitable, and whether it contains any traces of life, extinct or still active.
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Discovering traces of life on Mars would be of tremendous scientific significance: The first time that any signs of extraterrestrial life had ever been detected. Many people would also find it heartening to learn that we're not entirely alone in this vast, cold cosmos.

They shouldn't. If they were wise, they'd hope that our probes discover nothing. It would be great news to find that Mars is a completely sterile planet.

On the other hand, if we discovered traces of some simple extinct life form - a bacterium, some algae - it would be bad news. If we found fossils of something even more advanced, like a trilobite or even the skeleton of a small mammal, it would be horrible news. The more complex the life we found, the more depressing. Scientifically interesting, yes, but dire news for the future of the human race.

Why? To understand the real meaning of such a discovery is to realize just what it means that the universe has been so silent for so long - why we have been listening for other civilizations for decades and yet have heard nothing.