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With this essay by Ray Villard, news director for the Hubble Space Telescope, Astrobiology Magazine presents another in our series of 'Gedanken', or thought, experiments - musings by noted scientists on scientific mysteries in a series of "what if" scenarios. Gedanken experiments, which have been used for hundreds of years by scientists and philosophers to ponder thorny problems, this custom essays rely on the power of one's imagination to project these scenarios to logical conclusions.