NATIONAL HARBOR, Md. — Proposed budget reductions for the Hubble Space Telescope would impact research and outreach as well as increase the risk to the observatory, project officials warn.
At a town hall session during the 245th Meeting of the American Astronomical Society here Jan. 14, representatives of the Space Telescope Science Institute (STScI), which handles science operations of Hubble, said cuts in the telescope’s budget proposed by NASA could reduce the effectiveness of the nearly 35-year-old observatory.
As part of an ongoing senior review of astrophysics missions, NASA directed STScI to develop plans for Hubble for fiscal years 2026 through 2028 based on a budget of $83 million to $87.8 million annually, said Julia Roman-Duval, interim head of the Hubble Space Telescope Mission Office at the institute. That is a cut of more than 20% from current costs to run the telescope and handle science operations, she said.
STScI submitted its senior review proposal in December that described how it would run Hubble within those “in-guide” budget estimates, she said, one that requires some cutbacks. “There’s no in-guide scenario in which we can continue operating Hubble as we have in the past,” she said, including maintaining capabilities, grant funding and “mission risk posture.”
That proposal, she said, would result in “minimal support” for some instrument modes and cut grant funding for research using Hubble data from a historical average of about $30 million a year to $10 million. There would also be reductions in support for other science products and software associated with Hubble.
In addition, there would be increased risk to the mission in general because of reduced staff at STScI and NASA’s Goddard Space Flight Center supporting Hubble. “Those are the folks who are able to work around those ‘unknown unknowns’ and anomalies, and so not having them around would mean that the mission risk would increase.”
The institute has already been working to reduce costs in fiscal year 2025 after NASA proposed a budget of about $89 million for Hubble. That includes a 35% cut in outreach, with social media accounts for Hubble shut down last October and hubblesite.org, a website with Hubble imagery and press releases, to be shut down and content moved to a NASA website in March. There will also be a reduction in grant funding to $15.9 million and “compressed” science operations costs.
“We’re all feeling the pain of budget reductions,” Roman-Duval said. The reductions for 2025, though, are intended to avoid any immediate cuts in Hubble’s capability while the senior review is ongoing. “With this approach, we delay any irreversible changes until we have more certainty on where the budget scenarios are headed.”
STScI is scheduled to discuss its proposal to the NASA panel handling the senior review in February, she said, with final recommendations by the review given to NASA astrophysics leadership in late spring.
The sharp proposed cuts come after years of flat finding for Hubble, with $98.3 million a year for much of the 2010s and an average of $93.8 million for fiscal years 2020 through 2024. However, that put more gradual pressure on Hubble operations as the flat funding did not keep up with inflation, effectively eroding its budget by 30%. In 2022, NASA proposed to mitigate the effects of inflation by removing a fellowship program that cost $8 million that had been part of Hubble, but subsequent agency budget proposals both kept that program within Hubble and kept the mission’s overall budget flat.
Officials emphasized that Hubble itself continues to perform well despite its age and issues like a gyro failure that led NASA in June to switch to a reduced single-gyro mode last June. Roman-Duval said the project was confident that Hubble could continue to operate into the 2030s.
Demand for Hubble remains high, with an oversubscription rate — the ratio of observing time requested by astronomers versus the time available — of 6:1 in the latest cycle of proposals.
“Hubble remains a scientific powerhouse despite flat budgets,” said Jennifer Lotz, director of STScI, at the town hall meeting. “Over the past 10 years, Hubble has produced 30% more science with effectively 30% less spending power.”
She noted that it is still possible that either NASA will find additional funding for Hubble during the senior review process or will be directed by Congress to do so, perhaps as part of a final fiscal year 2025 appropriations bill. “We’re hoping for the best but preparing for the worst.”
She warned that budget problems Hubble is facing now could be a harbinger for similar issues soon for the James Webb Space Telescope, also operated by STScI. “Webb is not immune from the current challenges that we have with NASA’s budget. Inflation is real. There are really tight budgets at NASA, and there’s a potential for risk to JWST support starting as early as October.”
