Astronomers are scrambling to save the world's most powerful X-ray space telescope

The most powerful X-ray telescope ever built has reached its landmark 25th anniversary in space — but back on Earth, astronomers worry that its future is very much in doubt.

Supporters of the Chandra X-ray Observatory say the school bus-sized instrument is healthy and could keep doing science for another decade, but NASA recently announced a plan to slash its funding and effectively wrap up the mission.

The agency's head of astrophysics, Mark Clampin, has said that officials are facing a tough budget situation, and that hard choices have to be made to free up money to develop future telescopes, like one that will search for habitable planets that could potentially support life.

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But many astronomers can't fathom pulling the plug on Chandra, a one-of-a-kind instrument that's currently being used in tandem with the Hubble Space Telescope and the James Webb Space Telescope to make important discoveries.

"Just recently Chandra teamed up with the James Webb telescope to discover this supermassive black hole at the edge of the universe. It was the earliest black hole, the most distant black hole ever discovered," says David Pooley of Trinity University, an astronomer who has been using Chandra since it launched into orbit in a space shuttle back in 1999.

X-rays offer a way to study some of the most exotic phenomena in the universe, as they get generated during extreme cosmic events that heat matter up to millions of degrees. They can only be observed from space, rather than by ground telescopes, because incoming X-rays get absorbed by the Earth's atmosphere.

Pooley says there's no other telescope like Chandra and that losing it would be a serious blow.

"Its ability to detect distant objects is unmatched by any other X-ray telescope that's ever been built or will be built and operating — for at least another decade, likely two decades," Pooley says. "Turning off this great observatory for a relatively small cost savings would severely damage the U.S.'s leadership in this entire field."

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NASA's planned budget cuts would soon require laying off much of the staff that operates the telescope, meaning dozens of astronomers would be out looking for a job, according to a pressure campaign that has sprung up to try to reverse the decision.

According to astronomer Grant Tremblay, layoffs were expected to be announced in August and staffers would be gone by October.

"Most have families, kids in school, roots planted, and so a huge number will be forced to leave astronomy," he noted in a post on X, the platform formerly known as Twitter.

Pooley says everyone understands budget constraints, but he just disagrees with cutting a productive workhorse that's already in space in favor of "something twenty years down the road. I don't think that is a very good use of the taxpayer's money."

Chandra experts like Paul Levitt have taken to social media to express their displeasure.

Scientists have also appealed to members of Congress like Seth Moulton, a Democratic U. S. representative from Massachusetts, which is home to the telescope's operations center.

"I'm listening to the over 700 astronomers who have signed a letter saying, 'This work is important. It needs to continue,'" Moulton told NPR. "I really think it's up to those of us in Congress to try to find the money to ensure that it does."

Meanwhile, on Tuesday a meeting of the agency's astrophysics advisory committee will discuss Chandra's future. Part of that discussion will cover the results of a review that NASA initiated to see how well this telescope, as well as the aging Hubble, could be operated on a reduced budget.

"NASA will share its decisions, taking input from the review's findings, in a virtual town hall in the coming weeks," a NASA spokesperson told NPR by email.

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