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Astrophysicist Neil deGrasse Tyson is the director of the American Museum of Natural History’s Hayden Planetarium and a space expert so enthusiastic, we couldn’t help putting him on this list again this year. Appointed by former President George W. Bush to serve on both the Commission on the Future of the United States Aerospace Industry and the President’s Commission on Implementation of United States Space Exploration Policy, Tyson began hosting PBS’s NOVA ScienceNOW series in 2006.
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