Eight Months to Save a $500 Million Telescope

Katalyst Space Technologies has a June window to catch a falling $500 million NASA telescope before it burns up — and that window just got a lot more concrete.

The company's Link servicing spacecraft completed environmental testing at NASA's Goddard Space Flight Center on May 4 and returned to Katalyst's Colorado facilities for final prelaunch work, SpaceFlight Now reported. The mission: dock with NASA's Neil Gehrels Swift Observatory — a spacecraft that has no grapple fixtures and was never designed to be captured — and fire ion thrusters to push it back up to a stable altitude before orbital decay drags it into the atmosphere by year's end.

The urgency is not hypothetical. Swift's orbit is falling faster than expected — recent solar activity has heated the upper atmosphere, increasing drag on the spacecraft and accelerating its descent from roughly 600 kilometers to around 400 kilometers, with reentry expected before the end of 2026 if nothing is done. Below roughly 320 kilometers, the risk profile for a docking approach becomes unacceptable. The clock on that window has been running since February, when NASA began shutting down Swift's science instruments — not to save power for the rescue, but because the orbit decay was already underway and every watt drew the spacecraft down faster.

NASA had already suspended the UV/optical and X-ray telescopes in February and the Burst Alert Telescope instrument in April — "to reduce drag and extend the available window" for a boost attempt, in the agency's own words. The Burst Alert Telescope is the instrument that finds gamma-ray bursts in the first place. Since February, the most energetic explosions in the universe have been flying past a telescope that can't see them.

The $30 million NASA contract — awarded under the Small Business Innovation Research Phase 3 program, roughly 6 percent of what Swift has cost to build, launch, and operate over its 21-year lifetime — was framed as a straightforward value calculation. But the timeline is not negotiable. By late summer or early fall, Swift will slip below 200 miles — too low for Katalyst to have confidence in controlling its spacecraft during a docking approach.

"We realized that you can't get 100 percent guaranteed success on this," Ghonhee Lee, founder and CEO of Katalyst, told Ars Technica. "It's really technically ambitious."

Katalyst chose the Pegasus XL launch vehicle for reasons that are equal parts physics and geometry. Swift orbits at an inclination of about 21 degrees to avoid the South Atlantic Anomaly, where the planet's inner radiation belt dips closest to Earth's surface. Pegasus air-launches from Kwajalein Atoll near the equator, giving it a geometric advantage for reaching the right orbital plane without the propellant penalty of inclining a ground-launched rocket. Northrop Grumman has one Pegasus XL in storage for the mission; the company says it has maintained expertise on the vehicle through missile defense work, bringing back retired engineers for the Swift campaign.

There's nothing under this program that is inventing new technology, Lee told Ars. What is novel is doing it on this timeline, with a noncooperative target, for this price.

Link is an intermediate design between Katalyst's earlier small satellites and its planned Nexus platform — a more capable servicing bus intended for geostationary orbit missions. Per Ars Technica, this will be the company's first attempt to dock with another object in space. It has flown two spacecraft before. Neither was designed to be caught.

"We're in an unusual situation where the schedule dictates how much risk we're willing to accept, rather than the other way around," said Kieran Wilson, Link's principal investigator, in a NASA press release. "The clock is ticking on Swift's descent, so we have to find a balance between testing and problem solving that gives the mission the best chance of success."

A successful rescue would be the first time a commercial robotic spacecraft has captured and repositioned a government satellite that was never designed to be serviced. It would also establish a precedent for the growing number of expensive satellites in low Earth orbit that have no propulsion of their own. NASA has already indicated it views orbital servicing as part of its long-term approach to managing infrastructure in space. Clayton Turner, associate administrator for space technology at NASA, put it plainly: "By working with industry, NASA fosters rapid, agile technology development, advancing capabilities to benefit the missions of tomorrow."

The rocket is waiting. The spacecraft is almost ready. And for as long as Link's launch keeps slipping, the bursts keep flying past a telescope that can't watch for them.