The Trump administration has released a proposal to cut about a quarter of NASA’s 2026 budget, slashing both International Space Station crew sizes and the amount of research done there. At the same time, it sets up new funding that would likely benefit Elon Musk’s SpaceX by prioritizing human missions to Mars, and refocuses on “beating China back to the Moon.”

The suggested cuts are part of President Trump’s budget proposal for next year. It would slash $508 million from the ISS, cutting its crew size and focusing its “reduced research capacity … on efforts critical to the Moon and Mars exploration programs.” It also cuts $2.265 billion from space science missions, and includes terminating things like the Mars Sample Return mission, the objectives of which it says would be achieved by human flights to the red planet.

At the same time, the proposal offers $1 billion in spending on “Mars-focused programs,” with no specifics about where that money would go. As The New York Times writes, Musk’s SpaceX will “presumably” seek NASA funding to help with an uncrewed Starship flight to Mars that Musk has claimed will launch next year. Another $7 billion would be allocated to lunar exploration but suggests phasing out NASA’s SLS rocket and Orion capsule in favor of future commercial alternatives. It would end the Lunar Gateway program after the Artemis III mission, according to NASA.

The plan cuts $1.161 billion from earth sciences, eliminating funding for things like “low-priority climate monitoring satellites.” And it would slash $346 million in spending on “climate-focused ’green aviation’” in favor of air traffic control and defense spending, as well as $143 million in STEM engagement programs.

Casey Dreier, chief of space policy at space exploration advocate nonprofit Planetary Society, told The New York Times that the proposal is “the largest single-year cut to NASA in American history” and that it signals that “America is done leading the world in space, that we are a nation turning inward.”