Ending NASA’s Chandra Will Lower Us Out of the Excessive-Decision X-Ray Universe

Ending NASA’s Chandra Will Lower Us Out of the Excessive-Decision X-Ray Universe

By María Arias

The Chandra X-ray Observatory is the darling of high-energy astrophysics. Famed for offering unequaled x-ray views of voracious supermassive black holes, exploding huge stars and even darkish matter-infused collisions between galaxy clusters, the spacecraft probes the largest mysteries in astrophysics.

However 25 years after seeing its first mild, Chandra’s future is up within the air.

In March NASA slashed Chandra’s funds from $68 million in 2024 to $41 million in 2025 and $26 million a 12 months later. In keeping with the Chandra X-ray Middle, which operates the telescope, this solely permits for mission closeout. Within the months since, a collection of occasions—together with an intense publicity marketing campaign and a present of congressional assist—has stored Chandra funded by September 2025. However for this 12 months’s Senior Evaluate, which evaluates NASA’s missions, the Chandra X-ray Middle has been informed to remain throughout the proposed funds numbers—that’s, to plan how the spacecraft will shut down.

This can be a mistake. Chandra ought to stay operational till it encounters a essential failure or is changed by a comparable mission. Chandra is the solely excessive angular decision x-ray telescope in house, and there’s no mission with comparable capabilities scheduled to exchange it till 2032 on the earliest.

One may ask: What new discoveries can Chandra make that it hasn’t revamped the previous 25 years? And that’s a great query. However our observational capabilities have modified vastly since Chandra was launched, and due to this fact so has its potential for making discoveries that require a number of telescopes. We have now solely just lately reached the period of multiwavelength, multimessenger astrophysics, permitting simultaneous views of stars and galaxies in every part from the radio spectrum to gamma rays, neutrinos and gravitational waves. A lot of that essential synergy might be misplaced and squandered if we quit on the high-resolution x-ray protection.

In a way, Chandra was forward of its time. A few of the discoveries it is going to be remembered for, such because the detection of sound waves from supermassive black holes, are Chandra-only science. However its most important current outcomes come from the mixture of its eager x-ray imaginative and prescient with new devices such because the James Webb Area Telescope or the Occasion Horizon Telescope.

In 2017, when the emitted gravitational waves of two merging neutron stars reached Earth, all the foremost observatories on the earth performed follow-up observations on this historic, never-before-seen celestial occasion. The binary neutron star merger resulted in a kilonova explosion, which shone throughout the electromagnetic spectrum. Its x-ray emission was because of the explosion’s blast wave accelerating particles and gave us details about the fabric surrounding the binary. No different facility may have localized the merger as precisely as Chandra did: our understanding of one of the crucial essential astrophysical occasions of recent instances could be incomplete with out it.

After a quarter-century of operations, Chandra is a well-oiled machine, with a extremely skilled workforce that has tailored to the ageing telescope. Maintaining Chandra up and working on the forefront of astronomy “is getting more complex, but it’s not getting costlier. We’re just getting better at it every single day,” says Daniel Castro, an astrophysicist at Chandra Science Operations.

The crux of the matter lies within the presidential funds request from final March, which to communal consternation mischaracterized Chandra as quickly degrading and more and more costly. An additional supply of frustration throughout the neighborhood is that NASA sidestepped its personal peer-review process for evaluating the timeliness of mission closeout, the Senior Evaluate (which had given Chandra high marks in 2022), by unexpectedly chopping Chandra’s funding. The funds cuts finish Chandra’s mission with none dialogue or enter from the astrophysics neighborhood.

An fascinating alternative of NASA’s was to award $50 million to the event of the Liveable Worlds Observatory, or HWO, the place the identical funding would hold Chandra totally operational. HWO is an infrared, optical and ultraviolet NASA flagship telescope that’s 20 to 30 years from launch, and which is able to probably price greater than its estimated $6 to $10 billion.

Webb, whose prices ballooned from an preliminary $2 billion to $8 billion, looms giant within the determination to prioritize funding for HWO. It’s commendable that NASA is maintaining a tally of future challenges, however plenty of this primary allocation of cash for HWO will go into preliminary overheads, comparable to constructing a venture workplace and establishing business partnerships. It’s value contemplating whether or not awarding $50 million, many years earlier than launch, to a multibillion-dollar mission justifies shutting down a mission as productive as Chandra.

Astronomers have thrown round concepts for different sources of funding for Chandra, comparable to promoting its operations to the Japanese or European Area businesses or counting on personal donations. Collaboration with different house businesses and firms is customary in astrophysics, however it’s a prolonged course of, and plenty of the know-how in Chandra is walled off by U.S. know-how switch restrictions. And NASA’s coverage directive, whereas it permits for donations, doesn’t enable for circumstances on their use. Moreover, do we would like (typically erratic) house billionaires to develop into basic science? Entry to the universe is a public good, and most of us astronomers want to keep away from the likelihood that oligarchs turn out to be its gatekeepers.

Killing Chandra highlights the strain inherent in flagship-style astronomical missions. They make gorgeous discoveries, however in addition they have a approach of absorbing the funds of medium-size or current missions. We want extra highly effective telescopes as a result of they open new parameter house, which is the way in which actually revolutionary discoveries get made. However there’s a delicate stability to be maintained right here: What are we giving up by allocating such early funding to HWO? I’d say we’re opening a window, however closing a door. We’re selecting to be blind to the high-resolution x-ray universe. And that’s a loss to science as an entire.

That is an opinion and evaluation article, and the views expressed by the writer or authors usually are not essentially these of Scientific American.