Is there lifeor has there ever been lifebeyond Earth? Scientists are trying to find out. One things for sure, if we find life elsewhere, it will probably be in conditions where people couldnt survive: Too hot or too cold, the wrong kind of air, too much solar radiation, or a host of other things that are deadly to humans. But life is robust, and on Earth it finds a way to thrive in the unlikeliest of conditions. The only absolute is that lifeat least on Earthneeds liquid water.
According to Gene McDonald at the Astrobiology Research Element at NASAs Jet Propulsion Laboratory (JPL), water has unique properties that make it the best solvent for the kind of chemistry that you need to start and sustain life. Neither ice nor water vapor will do. Biochemistry requires molecules to move around, which they cant do nearly as well in a solid. In vapor, its hard to keep parts together on a molecular level.
Why search for evidence of water on other planets?
What about life in the universe beyond our solar
Scientists at the SETI (Search for Extraterrestrial Intelligence) Institute, once directed by Carl Sagan, search for radio signals and other evidence that would indicate intelligent life beyond Earth. Find out more at SETI@home.
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