NASA Science Faces 47 Percent Cut and 40-Plus Mission Cancellations

The Trump administration's FY2027 budget would cut NASA's Science Mission Directorate from $7.25 billion to $3.9 billion — a 47 percent reduction that the administration says would "transform the Science program into one that is more focused and fiscally responsible." The cut would terminate more than 40 missions and represents the largest proposed single-year science cut in the agency's history.

NASA's overall budget would fall 23 percent to $18.8 billion, but science absorbs a disproportionate share of the reduction while lunar exploration programs remain relatively protected.

Which Missions and Programs Are on the Line

The budget explicitly names Mars Sample Return — a flagship program projected to cost up to $11 billion — and SERVIR, a $10 million annual program distributing Earth science data to developing nations, as termination targets.

Missions that Congress rescued from cancellation in FY2026 are again at risk, including the Chandra X-Ray Observatory, the Astrophysics Probe mission, and OSIRIS-APEX. The Earth Systems Explorers program, which selected two missions (STRIVE and EDGE) for development in February, would see funding support only one mission within the five-year budget window.

The remaining 30-plus missions slated for termination have not been publicly identified.

Science Community Calls It an 'Extinction-Level Event'

Casey Dreier, chief of space policy at The Planetary Society, called the proposal "an extinction-level event for science" that "would undermine NASA's world leader status." The cuts would ripple through university research labs, aerospace contractors, and the pipeline of early-career scientists whose work depends on NASA-funded missions and data.

NASA Administrator Jared Isaacman has publicly backed the budget framework, creating an unusual dynamic where the agency's own leadership supports cuts that its scientific community overwhelmingly opposes.

What Space Science Grant Seekers Should Do

Researchers with proposals tied to at-risk missions should identify whether their work can be redirected toward surviving programs. Principal investigators on the 40-plus targeted missions should engage with their NASA program managers about transition options.

Congress restored NASA science funding last year, and space science advocates are already mobilizing. Researchers can track NASA and other federal science opportunities at grantedai.com.

In-depth analysis of which NASA science programs are most vulnerable and how researchers can adapt is available on the Granted blog.