The White House wants to cut NASA's Science Mission Directorate by 47% for the second consecutive year. Last time Congress said no. The question this year is whether the political math has changed.
The Office of Management and Budget released its fiscal year 2027 budget overview on April 3, proposing $18.8 billion for NASA overall, a 23% reduction from what the agency received in the final FY2026 appropriations bill passed in January. Within that, NASA science would drop from $7.25 billion to $3.9 billion. OMB's own document states it "terminates over 40 low-priority missions to transform the Science program into one that is more focused and fiscally responsible."
The comparison to last year's proposal is exact. OMB proposed the same $18.8 billion top line for NASA in FY2026, also sought roughly similar cuts to science, and Congress rejected the proposal outright, instead passing a full-year appropriation in January that protected NASA science with statutory language. More than 100 members of Congress, nearly all Democrats, signed a letter in March urging appropriators to increase NASA science funding to $9 billion in FY2027, a 25% increase over FY2026 levels.
The FY2026 budget fight lasted a month and produced a government shutdown before concluding. The detailed FY2027 proposal NASA released, at 384 pages, is less than half the length of the 2025 request and notably omits previously protected missions. Chandra X-Ray Observatory, Astrophysics Probe, and OSIRIS-APEX were all proposed for cancellation in FY2026 and revived by Congress. None appear in the FY2027 document. Earth Systems Explorers, which selected two missions (STRIVE and EDGE) for development in February, gets one mission in the five-year budget window.
What makes this year's proposal structurally different is the person in charge of NASA's response. Jared Isaacman, the billionaire founder of Shift4 Payments and two-time private astronaut, was sworn in as NASA Administrator on December 18, 2025. He immediately unveiled an ambitious agenda called "Ignition" at a NASA event: crewed lunar landings, a lunar surface station, a nuclear-propelled Mars mission, and what he described as sustained support for ongoing science. The lunar base alone carries an estimated $20 billion price tag over seven years. Isaacman has also overseen workforce regrowth following a reported loss of over 4,000 NASA civil servants under the previous leadership gap.
OMB's cut to science does not scale proportionally with the exploration increase. The Science Mission Directorate loses $3.4 billion. Exploration gains roughly $800 million, a 10% bump to $8.5 billion. The math does not close the gap for the missions that would be terminated. The Planetary Society put it plainly in the organization's statement: "The President has stated his desire that NASA remain the world's premier space agency. The White House's budgeting office is out of step with this broad, bipartisan consensus."
Congress has shown it will fight for NASA science. The question is whether Isaacman's agenda gives appropriators a new reason to fight harder, or whether the second consecutive year of identical proposals from OMB makes the fight feel settled before it starts. The budget is a request. The fights that matter will happen in the authorization and appropriations committees.