November 15, 2024
4 min learn
Ending NASA’s Chandra Will Lower Us Out of the Excessive-Decision X-Ray Universe
The Chandra X-ray Observatory is going through closure. Shutting it down could be a loss to science as an entire
NASA’s Chandra X-ray Observatory as it could seem at about 50,000 miles from the Earth, almost twice as excessive as Earth-orbiting geosynchronous satellites.
Walter Myers/Stocktrek Pictures Inc. Alamy Inventory Picture
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 price range from $68 million in 2024 to $41 million in 2025 and $26 million a yr later. In line with the Chandra X-ray Heart, 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 help—has stored Chandra funded by September 2025. However for this yr’s Senior Overview, which evaluates NASA’s missions, the Chandra X-ray Heart has been instructed to remain inside the proposed price range numbers—that’s, to plan how the spacecraft will shut down.
It is a mistake. Chandra ought to stay operational till it encounters a vital failure or is changed by a comparable mission. Chandra is the solely excessive angular decision x-ray telescope in area, and there’s no mission with comparable capabilities scheduled to switch it till 2032 on the earliest.
One might 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 enormously since Chandra was launched, and due to this fact so has its potential for making discoveries that require a number of telescopes. Now we have solely not too long ago reached the period of multiwavelength, multimessenger astrophysics, permitting simultaneous views of stars and galaxies in every little thing from the radio spectrum to gamma rays, neutrinos and gravitational waves. A lot of that vital synergy shall be misplaced and squandered if we quit 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 latest 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 area 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 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. Holding Chandra up and operating 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 price range request from final March, which to communal consternation mischaracterized Chandra as quickly degrading and more and more costly. An additional supply of frustration inside the neighborhood is that NASA sidestepped its personal peer-review process for evaluating the timeliness of mission closeout, the Senior Overview (which had given Chandra prime marks in 2022), by unexpectedly chopping Chandra’s funding. The price range 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 maintain Chandra totally operational. HWO is an infrared, optical and ultraviolet NASA flagship telescope that’s 20 to 30 years from launch, and which can most 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 resolution to prioritize funding for HWO. It’s commendable that NASA is keeping track of future challenges, however quite a lot of this primary allocation of cash for HWO will go into preliminary overheads, reminiscent of constructing a mission workplace and establishing trade partnerships. It’s price contemplating whether or not awarding $50 million, a long time 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, reminiscent of promoting its operations to the Japanese or European Area businesses or counting on personal donations. Collaboration with different area businesses and corporations is normal in astrophysics, however it’s a prolonged course of, and quite a lot 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. Moreover, do we would like (generally erratic) area 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 chance that oligarchs develop into its gatekeepers.
Killing Chandra highlights the strain inherent in flagship-style astronomical missions. They make beautiful discoveries, however additionally they have a method of absorbing the price range of medium-size or current missions. We want extra highly effective telescopes as a result of they open new parameter area, which is the way in which really revolutionary discoveries get made. However there’s a delicate steadiness 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 should not essentially these of Scientific American.
