NASA’s FY2025 Budget Proposal Would Doom Chandra

If Congress adopts NASA’s FY2025 astrophysics budget request, the Chandra X-ray telescope cannot continue to operate according to an independent review. Chandra advocates have been raising the alarm since the request was submitted in March and the Operating Paradigm Change Review led by two renowned astrophysicists confirms those fears. NASA is seeking cost savings by reducing operations of both Chandra and Hubble, two of its oldest space telescopes, but Chandra would be hit the hardest.

Rob Kennicutt briefed NASA’s Astrophysics Advisory Committee (APAC) yesterday about the OPCR findings. The University of Arizona and Texas A&M astronomer, who co-chaired the most recent astrophysics Decadal Survey from the National Academies of Science, Engineering, and Medicine, spoke on behalf of the OPCR. The review was chaired by John Mather from NASA’s Goddard Space Flight Center, who won the Nobel Prize in Physics in 2006.

NASA’s science budget is under strain because of funding cuts resulting from last year’s Fiscal Responsibility Act. Congress cut NASA’s FY2024 budget not just below the Administration’s request, but two percent below what it had for FY2023. The agency is looking for cost savings in every nook and cranny and operations of the 25-year-old Chandra and the 34-year-old Hubble are targets.

Chandra is the only U.S. space telescope that observes the universe in the X-ray portion of the spectrum. X-rays don’t penetrate Earth’s atmosphere, so those studies must be done in space. Hubble sees the cosmos mostly in the visible wavelengths, but some ultraviolet  and infrared. Probably the best known of NASA’s space telescopes because it was serviced by five space shuttle crews, Hubble was just declared good to go for at least another decade despite problems with its gyroscopes.

The FY2025 budget request pending before Congress would cut operations of both, but Chandra would be hit harder.

Kennicutt said the OPCR was not asked to make recommendations, but only to evaluate the two telescopes in terms of their “scientific merit, relevance and responsiveness, and technical capability, management and science productivity given the costs.”  Representatives of the two telescopes each had 90 minutes to make their cases to the committee in May.

The committee found that both telescopes are operating well, making important scientific discoveries, and could continue “well into the next decade.” Kennicutt stressed their review was not because of any problems with the telescopes, but “because NASA needs to save money.”  Ending either of them would be “premature and would have a large, permanent impact on science and the astronomical community.”

NASA’s FY2025 budget request, which includes projections through FY2029, shows a gradual decline in funding for Hubble from $93.3 million in FY2023 to $64.7 million in FY2029. Chandra’s cutbacks are more dramatic and immediate, from $68.3 million in FY2023 to $41.1 million in FY2025, to $26.6 million in FY2026, FY2027, and FY2028, and $5.2 million in FY2029.

The committee’s bottom line was that Hubble could continue reduced operations at that level, but not Chandra.

The Hubble and Chandra teams each presented four options as to how they could operate at the levels in the FY2025 request — or not. The Hubble team, with more money to spend, had three options to continue operations at reduced levels. The Chandra team had none. The only options that continued some degree of useful operations were above the funding levels in the NASA proposal.

Kennicutt said the OPCR concluded there is “no way” to continue operating a scientifically viable Chandra (CXC) space telescope within the funding guidance in the request. “This is a serious threat to the observatory.”

While OPCR did not make recommendations, Kennicutt said they concluded Chandra could be operated for less money, but not as little as in the budget request. For example, the Chandra team’s Option II would reduce costs somewhat and allow the telescope to continue producing important science, although it’s more money than NASA is proposing.

APAC is an advisory committee to NASA Astrophysics Division Director Mark Clampin, who established the OPCR and participated in the APAC meeting yesterday and today. He made clear he was not asking for advice from APAC, however, simply informing them of the results of the OPCR review as they requested. He said the decision about Chandra is being driven by the budget process and likely will be announced in mid-September.

The House Appropriations Committee expressed support for Chandra during an April hearing with NASA Administrator Bill Nelson and when it marked up the FY2025 Commerce-Justice-Science bill, but did not direct the agency to spend a specific amount of money.  “The Committee supports continued funding for the Chandra X–Ray Observatory, which continues to deliver discoveries addressing a wide range of questions across astrophysics.”

The Senate Appropriations Committee will mark up its version of the bill tomorrow.

Launched on the space shuttle on July 23, 1999, Chandra is operated by the Center for Astrophysics|Harvard Smithsonian and celebrated its 25 birthday yesterday. They released a video with 25 never-before-seen views of the cosmos from Chandra.

Astrophysics is just one part of NASA’s science budget affected by the budget cuts driven by the Fiscal Responsibility Act. For the current fiscal year, FY2024, the Science Mission Directorate got about $1 billion less than requested. NASA announced last week it intends to cancel the VIPER lunar rover because of cost growth and the constrained budget outlook.  It also has paused the Mars Sample Return mission while it seeks innovative ideas on how to return the samples of Mars now being collected by the Perseverance rover back to Earth more affordably.

Congress ultimately will decide the fate of all these programs. NASA has proposed canceling missions in the past only to be directed to continue them, although Congress does not always provide the requisite money and the agency has to take it from other activities creating another set of problems.