November 15, 2024
4 min learn
Ending NASA’s Chandra Will Reduce Us Out of the Excessive-Decision X-Ray Universe
The Chandra X-ray Observatory is dealing with closure. Shutting it down could be a loss to science as an entire
NASA’s Chandra X-ray Observatory as it might seem at about 50,000 miles from the Earth, practically twice as excessive as Earth-orbiting geosynchronous satellites.
Walter Myers/Stocktrek Pictures Inc. Alamy Inventory Photograph
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 large 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 finances from $68 million in 2024 to $41 million in 2025 and $26 million a yr later. Based on the Chandra X-ray Middle, which operates the telescope, this solely permits for mission closeout. Within the months since, a sequence of occasions—together with an intense publicity marketing campaign and a present of congressional help—has saved Chandra funded via September 2025. However for this yr’s Senior Evaluation, which evaluates NASA’s missions, the Chandra X-ray Middle has been advised to remain inside the proposed finances 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 crucial 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 might ask: What new discoveries can Chandra make that it hasn’t remodeled the previous 25 years? And that’s query. However our observational capabilities have modified vastly since Chandra was launched, and subsequently so has its potential for making discoveries that require a number of telescopes. We’ve got solely 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 crucial synergy will likely be misplaced and squandered if we hand over on the high-resolution x-ray protection.
In a way, Chandra was forward of its time. Among the discoveries will probably be remembered for, such because the detection of sound waves from supermassive black holes, are Chandra-only science. However its most vital current outcomes come from the mix of its eager x-ray imaginative and prescient with new devices such because the James Webb Area Telescope or the Occasion Horizon Telescope.
The Chandra X-Ray Observatory was the heaviest payload to be carried into house by a shuttle. It has been supernovas, black holes and spiral galaxies for 20 years.
In 2017, when the emitted gravitational waves of two merging neutron stars reached Earth, all the key observatories on this planet 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 as a result of explosion’s blast wave accelerating particles and gave us details about the fabric surrounding the binary. No different facility might have localized the merger as precisely as Chandra did: our understanding of one of the vital vital astrophysical occasions of contemporary instances could be incomplete with out it.
After a quarter-century of operations, Chandra is a well-oiled machine, with a extremely skilled crew that has tailored to the ageing telescope. Maintaining Chandra up and working on the forefront of astronomy “is getting extra complicated, nevertheless it’s not getting costlier. We’re simply getting higher at it each single day,” says Daniel Castro, an astrophysicist at Chandra Science Operations.
The crux of the matter lies within the presidential finances request from final March, which to communal consternation mischaracterized Chandra as quickly degrading and more and more costly. An extra supply of frustration inside the group is that NASA sidestepped its personal peer-review process for evaluating the timeliness of mission closeout, the Senior Evaluation (which had given Chandra high marks in 2022), by unexpectedly reducing Chandra’s funding. The finances cuts finish Chandra’s mission with none dialogue or enter from the astrophysics group.
An fascinating selection 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 can almost certainly value greater than its estimated $6 to $10 billion.
Webb, whose prices ballooned from an preliminary $2 billion to $8 billion, looms massive 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, corresponding to constructing a venture workplace and establishing trade partnerships. It’s price 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, corresponding to promoting its operations to the Japanese or European Area businesses or counting on non-public donations. Collaboration with different house businesses and corporations is commonplace in astrophysics, however it’s a prolonged course of, and plenty of the expertise in Chandra is walled off by U.S. expertise switch restrictions. And NASA’s coverage directive, whereas it permits for donations, doesn’t enable for circumstances on their use. Apart from, do we wish (typically erratic) house billionaires to increase into elementary science? Entry to the universe is a public good, and most of us astronomers wish to keep away from the likelihood that oligarchs develop into its gatekeepers.
Killing Chandra highlights the stress inherent in flagship-style astronomical missions. They make gorgeous discoveries, however additionally they have a method of absorbing the finances of medium-size or present missions. We want extra highly effective telescopes as a result of they open new parameter house, which is the best way 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 aren’t essentially these of Scientific American.
