Jared Isaacman, tapped by President-elect Donald Trump as the next NASA administrator, is the billionaire founder of payment processing company Shift4 Payments with ties to Elon Musk's SpaceX, and an aspiring astronaut who participated in the world's first commercial spacewalk.

Forbes estimates Isaacman is worth about $1.8 billion as of Wednesday. Much of his wealth comes from his 38% stake in Shift4 Payments.

On Wednesday, Trump announced Isaacman as his nominee for NASA administrator. In a Truth Social post, Trump referred to Isaacman as an "accomplished business leader, philanthropist, pilot and astronaut" while citing his "passion for space" that would lead NASA "into a bold new era." Isaacman said he was "honored" to receive Trump's nomination and suggested there will "inevitably be a thriving space economy."

Isaacman has said his Polaris missions will contribute to SpaceX's mission of sending humans to the moon and Mars, echoing Musk's call to send colonizing missions to Mars. Isaacman's first Polaris mission was the first of three planned missions funded and executed by Isaacman for space technology development purposes. The mission tested new extra-vehicular activity spacesuits developed by SpaceX, which were designed to be more flexible and cost-effective, and they conducted an experiment to determine whether the radiation in space can take X-ray images without an X-ray machine. Isaacman's Inspiration4 was the first space mission populated only by tourists, and was commissioned as a fundraiser for St. Jude Children's hospital.

870. That's how many miles the Polaris Dawn mission traveled from Earth at its furthest point.

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