CAPE CANAVERAL, Fla. (AP) — Billionaire spacewalker Jared Isaacman urged senators on Wednesday to take swift action on his bid to lead NASA , after being yanked and then renominated by President Donald Trump.

Isaacman appeared before the Commerce, Science and Transportation Committee in Washington eight months after his first nomination hearing . The tech entrepreneur who's rocketed into orbit twice with SpaceX stressed the need for “full-time leadership” at NASA as the space agency prepares to send astronauts back to the moon early next year.

Transportation Secretary Sean Duffy has been filling in as NASA's acting administrator since summer.

Returning astronauts to the moon for the first time in more than 50 years will be “a challenging endeavor to say the least,” Isaacman tol

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