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Robert Lightfoot, NASA’s acting administrator for the past 14 months, announced March 12 that he will retire April 30.“I will work with the White House on a smooth transition to the new administrator,” Lightfoot wrote in a note to NASA employees. It is unclear who the new administrator will be. President Donald Trump has nominated Rep. Jim Bridenstine (R-Okla.) to be NASA’s permanent head, but the conservative congressman faces opposition from senators who object to having a politician run what has traditionally…
