WASHINGTON — Several members of Congress are seeking more details about the operation of NASA’s Chandra X-ray Observatory, a space telescope whose budget has faced steep cuts.

In an Oct. 30 letter to Patrick Slane, director of the Chandra X-ray Center, six members of the Massachusetts congressional delegation, led by Sen. Elizabeth Warren (D), asked for more details about the operation of the 25-year-old X-ray space telescope and the effects potential NASA budget cuts would have on it.

NASA had proposed a 40% cut in Chandra’s budget for fiscal year 2025 in the budget proposal the agency released in March. However, agency officials said at an Oct. 23 town hall meeting that it was delaying a decision on those cuts as well as smaller cuts to the Hubble Space Telescope until after Congress completes its fiscal year 2025 appropriations bills. The agency is also providing funding to Chandra to avoid layoffs at the center through the 2025 fiscal year.

“Shutting Chandra down would have had far-reaching impacts on the scientific community and U.S. leadership in astronomy,” the letter noted. “X-ray experts said they would leave the United States if Chandra was eliminated and the nation was left without an X-ray telescope, resulting in the possibility of the United States ceding X-ray telescope leadership to Europe, Japan, or China.”

The letter stated that NASA officials had informed the members that the agency will keep Chandra funded at “largely the same” level. “This funding will allow the telescope to remain fully operational, and we appreciate NASA’s support,” the members stated in the letter

The members noted their efforts to convince NASA to defer any decisions on Chandra’s budget until after the 2025 appropriations bills are complete. “We are glad NASA looked at the evidence we presented and decided to restore Chandra’s funding for another year, but Congress and NASA need to continue their support for X-ray astronomy,” the letter stated.

To “ensure Congress, NASA, and Chandra are looking toward the future,” the letter included more than a dozen questions about Chandra. Several focus on the scientific productivity of the telescope, such as demand for telescope time, and the impact on astronomy in general, and U.S. X-ray astronomy in particular, if Chandra is ended prematurely.

Other questions sought information on the cost of operating Chandra and any issues it has. NASA, when it announced the proposed budget cuts in March, argued that problems with thermal control of the telescope reduced its effectiveness, a claim astronomers who use Chandra rejected.

“How significant is the impact of thermal management on the life of Chandra and its operations?” the letter asked, also seeking details on any additional costs.

A final question asks about reductions of funding available for Chandra’s “general observer” program that makes observing time available to much of the astronomical community. “What are the impacts of cutting the General Observer program for scientists across the United States?” the letter asked.

The letter stated it is seeking responses from the Chandra X-ray Center by Nov. 15. A spokesperson for the center confirmed to SpaceNews Oct. 31 that they had received the letter and would respond by the deadline, but did not comment further.

Other members signing the letter are Sen. Edward Markey (D) and Reps. Seth Moulton (D), James McGovern (D), Stephen Lynch (D) and Lori Trajan (D). All are from Massachusetts; the Chandra X-ray Center is located in Cambridge, Massachusetts.