Nelson represented Florida’s Space Coast during his nearly two decades on Capitol Hill, where he was one of the space agency’s most vocal supporters.
Nelson, during his time in Congress, even famously flew on the space shuttle in 1986 as a payload specialist, making him the second sitting member of Congress to fly into space.
Nelson, as NASA administrator, will be tasked with leading the agency as it races to return American astronauts to the moon under the Trump-era Artemis program.
The White House, last month, said it supports the Artemis Program, which aims to land the first woman and the next man on the moon by 2024.
NASA published the Artemis Plan last year, which called for $28 billion for the moon program.
"With the Artemis program, NASA will land the first woman and next man on the Moon by 2024, using innovative technologies to explore more of the lunar surface than ever before," NASA said. "We will collaborate with our commercial and international partners and establish sustainable exploration by the end of the decade."
NASA added: "Then, we will use what we learn on and around the Moon to take the next giant leap – sending astronauts to Mars."
Initial mission capability for 2024 involves landing two astronauts on the moon’s South Pole. Astronauts will live and work out of the lander for six and a half days, according to NASA.