WASHINGTON — NASA Administrator Bill Nelson defended the agency’s plans to cut back or cancel some agency programs at a House hearing, placing much of the blame at the feet of Congress.

At a largely collegial 90-minute hearing of the House Appropriations Committee’s commerce, justice and science committee April 17 about NASA’s fiscal year 2025 budget proposal, Nelson faced questions from some members about plans to reduce spending on Mars Sample Return and cancel a satellite servicing mission.

Rep. David Trone (D-Md.) criticized NASA for its decision in March to cancel the On-Orbit Servicing, Assembly and Manufacturing (OSAM) 1 mission, with only $11 million proposed for the mission in fiscal year 2025 to close out the satellite servicing project. OSAM-1 is led by NASA’s Goddard Space Flight Center in Maryland.

“Canceling that program would be catastrophic for scientific innovation in Maryland and result in the loss of 1,200 jobs,” he said. NASA, in its announcement of the OSAM-1 cancellation, said 450 civil servants and contractors were working on the mission.

Nelson noted that OSAM-1 was years behind schedule and far beyond its original budget. Moreover, he said satellite servicing technologies and needs had changed from the original concept of that mission to refuel a spacecraft in low Earth orbit.

“We are, for ’25, basically wanting us to move on from OSAM,” he said, noting that NASA could continue work on the mission through the rest of the current fiscal year before closing it out. “In the parlance of the South, this dog doesn’t hunt.”

Nelson argued that the decision to cancel OSAM-1 was tied to broader fiscal pressures on the agency created by budget caps enacted by Congress last year for 2024 and 2025. “Understand the hand that you dealt us,” he told Trone. “With less money, we have to make some very tough choices. Your program is one of them. California’s program is another one.”

“California’s program” is a reference to Mars Sample Return, led by the Jet Propulsion Laboratory in the state. Rep. Mike Garcia (R-Calif.) reiterated his concerns about spending cuts to MSR, including NASA’s decision to spend $310 million on the program in 2024, which he noted was near the low end of the range allowed by Congress in its 2024 omnibus spending bill, with only $200 million proposed for 2025.

He said he was concerned about the potential for additional layoffs at JPL that could drop the lab below a “critical mass” needed to carry out missions. “I worry that, when we make certain decisions, that we’re cutting to the bone and, in this case, potentially amputating JPL.”

Nelson said he was “quite sanguine” about the future of both MSR and JPL, citing NASA’s plans to seek alternative architectures for the sample return mission as well as expectations that budget caps will be lifted after 2025. “I’m very optimistic, as I talk to our scientists, that it can be done.”

Near the end of the hearing, Rep. Joe Morelle (D-N.Y.) asked about another element of the budget proposal that has attracted controversy, a 40% reduction in the budget for the Chandra X-Ray Observatory. Astronomers have argued that the cut would bring the mission to a premature end.

Morelle noted the telescope has as much as a decade of useful life remaining. “I would think we would want to continue it,” he said.

“Remember I said we had to make hard choices,” Nelson responded, noting that Chandra has been in space for nearly 25 years. “And it’s time for new missions.” NASA has not approved development of any new large X-ray telescopes to replace Chandra.

Those hard choices, he reminded appropriators, were the result of the budget caps enacted last year as part of the deal to raise the debt ceiling and avoid a government default. “That’s the compromise you had to do,” he said. “If I had been a member, I would have voted for that, too, to save the full faith and credit of the U.S. government.”

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...