President Trump pulled the plug on Jared Isaacman running the National Aeronautics and Space Administration, shortly before the Senate was poised to vote on confirming him for the role.

The president plans to appoint a new nominee for the post soon, a White House spokeswoman said Saturday. "It's essential that the next leader of NASA is in complete alignment with President Trump's America First agenda," she said.

Isaacman and a spokeswoman for him couldn't be reached for comment.

Isaacman, a 42-year-old billionaire who founded and led payments-technology company Shift4 , gained renown after taking two private space flights to low-Earth orbit with Elon Musk's SpaceX. In September, he conducted the first spacewalk by a nongovernment astronaut.

Trump's nomination of Isaacman to run NASA marked a departure for the agency, which has usually been run by government officials or former politicians.

He was also different from many other officials in the Trump administration, having made political donations to both Democrats and Republicans. During an interview with The Wall Street Journal last November, Isaacman described himself as a political "hypermoderate."

The entrepreneur was a proponent of further tapping commercial-space companies to advance NASA's aims.

At a Senate Commerce Committee hearing in April, Isaacman sketched out a broad agenda for the agency, making the case that it could pursue ambitious exploration missions to both the moon and Mars.

Trump himself called for sending American astronauts to visit the red planet during his inauguration speech, a mission that has long been a goal of Musk. Many members of Congress have advocated for maintaining NASA's near-term plans to transport crews to the moon.

Isaacman's ties to SpaceX and Musk, who recently stepped down from his government role, drew scrutiny from some senators. He said at the Senate hearing he hadn't spoken or communicated with Musk since accepting the nomination, and that he would avoid any conflicts of interest with the company. A filing related to his nomination indicated he sold SpaceX stock that he previously held.

"They work for us, not the other way around," he said about SpaceX at the hearing.

In written remarks to the committee, Isaacman said the idea of reducing NASA's science budget by 50% "did not appear to be an optimal outcome." The committee later voted to send his nomination to the full Senate, which was expected to vote on his confirmation within the next few days.

The White House has since proposed a major budget cut at the space agency. On Friday, documents for the next government fiscal year suggested cutting NASA's budget to $18.8 billion from nearly $25 billion. That proposal would reduce the civilian workforce at the agency by 32% to around 11,900 employees.

Write to Micah Maidenberg at micah.maidenberg@wsj.com

(END) Dow Jones Newswires

May 31, 2025 18:49 ET (22:49 GMT)

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