President Donald Trump said late Wednesday that Transportation Secretary Sean Duffy will serve as interim administrator of the National Aeronautics and Space Administration, filling a vacancy created six weeks ago when the White House withdrew its earlier nominee. Trump announced the move on his Truth Social platform, praising Duffy’s performance at the Department of Transportation and calling him a “fantastic leader” for the space agency, even if only on a temporary basis. Duffy, 53, is a former Wisconsin congressman and reality-television personality who was confirmed as transportation secretary in January. He has no formal aerospace background and will continue to run the 55,000-person Transportation Department while overseeing NASA. His dual appointment is unusual; cabinet secretaries have not previously held the top job at the space agency concurrently. The change follows Trump’s 31 May decision to pull the nomination of billionaire private-astronaut Jared Isaacman, a close associate of SpaceX chief Elon Musk, citing what the president later called an “inappropriate” overlap with Musk’s business interests. With the Senate now reviewing the administration’s proposed fiscal-2026 budget—which would trim NASA’s overall funding by roughly a quarter and cut its science programs about in half—Duffy is expected to focus on implementing White House priorities while the search for a permanent administrator continues.