This year's budget expires at the end of this month, and Congress must act before October 1 to avert a government shutdown. If Congress passes a budget before then, it will most likely be in the form of a continuing resolution, an extension of this year's funding levels into the first few weeks or months of fiscal year 2026.

The White House's budget request for fiscal year 2026 calls for a 25 percent cut to NASA's overall budget, and a nearly 50 percent reduction in funding for the agency's Science Mission Directorate. These cuts would cut off money for at least 41 missions, including 19 already in space and many more far along in development.

Normally, a president's budget request isn't the final say on matters. Lawmakers in the House and Senate have written their own budget bills in the last several months. There are differences between each appropriations bill, but they broadly reject most of the Trump administration's proposed cuts.

Still, this hasn't quelled the anxieties of anyone with a professional or layman's interest in space science. The 19 active robotic missions chosen for cancellation are operating beyond their original design lifetime. However, in many cases, they are in pursuit of scientific data that no other mission has a chance of collecting for decades or longer.

A “tragic capitulation”
Some of the mission names are recognizable to anyone with a passing interest in NASA's work. They include the agency's two Orbiting Carbon Observatory missions monitoring data signatures related to climate change, the Chandra X-ray Observatory, which survived a budget scare last year, and two of NASA's three active satellites orbiting Mars.

And there's New Horizons, a spacecraft that made front-page headlines in 2015 when it beamed home the first up-close pictures of Pluto. Another mission on the chopping block is Juno, the world's only spacecraft currently at Jupiter.
Both spacecraft have more to offer, according to the scientists leading the missions.

“New Horizons is perfectly healthy," said Alan Stern, the mission's principal investigator at Southwest Research Institute (SWRI). "Everything on the spacecraft is working. All the spacecraft subsystems are performing perfectly, as close to perfectly as one could ever hope. And all the instruments are, too. The spacecraft has the fuel and power to run into the late 2040s or maybe 2050."

New Horizons is a decade and more than 2.5 billion miles (4.1 billion kilometers) beyond Pluto. The probe flew by a frozen object named Arrokoth on New Year's Day 2019, returning images of the most distant world ever explored by a spacecraft. Since then, the mission has continued its speedy departure from the Solar System and could become the third spacecraft to return data from interstellar space.