Enlarge / Oklahoma GOP Congressman Jim Bridenstine is Trump's nominee to become NASA administrator. (credit: Space Foundation) On Monday, Vice President Mike Pence delivered a space policy speech at a conference in Colorado. At the beginning of his talk, Pence singled out NASA's acting administrator Robert Lightfoot for a 30-year career at the space agency, and applauded his service. Left unstated was the fact that, at 15 months, Lightfoot has had by far the longest tenure of any acting administrator at NASA.