President Trump's second term kicked off with big plans for Mars but puzzling leadership at NASA. In his inaugural speech, Trump talked about sending astronauts to Mars, but there was confusion about who was in charge at NASA. Bill Nelson and Pam Melroy had just stepped down as administrator and deputy administrator, leaving the agency's top spot temporarily empty.

As Trump spoke, NASA's website said Jim Free was the acting administrator. Free is the associate administrator and highest-ranking civil servant at the agency. But later, the White House said Janet Petro, director of the Kennedy Space Center, would be acting administrator. It's not clear why there was a mix-up.

Traditionally, the associate administrator fills in as acting administrator during transitions. But presidents can choose anyone. The White House also nominated Jared Isaacman as the new NASA administrator. Isaacman is a billionaire who has been to space twice on SpaceX missions. It's not yet known when the Senate will hold a hearing for his confirmation.

Whoever is acting administrator right now might not stay long. The important thing is that NASA keeps working on its missions while the White House figures things out.

NASA's Top Job in Flux as Trump's Second Term Begins

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