A robot meant to rescue NASA’s aging Swift observatory never caught it

Katalyst Space’s LINK robotic spacecraft, built in under a year to grab NASA’s Neil Gehrels Swift Observatory and push it into a higher orbit, never touched its target. LINK re-entered Earth’s atmosphere on Sept. 25, 2026, according to NASA, after intermittent communications losses and orientation control problems ended the plan to capture Swift.

Swift, launched in November 2004, is still in orbit and still sinking. NASA published a lessons-learned account of the boost mission on Sept. 28, and the agency’s Swift blog gave the latest altitude it has published: about 200 miles on Sept. 25, with the agency’s own estimate that the observatory would reach the altitude where science stops within weeks.

A Rescue Built on a One-Year Schedule

NASA’s problem was atmospheric drag. Swift’s low Earth orbit began to decay rapidly after more than 21 years of science operations because of increased solar activity, and without intervention the observatory was expected to re-enter by the end of 2026. In September 2025, according to NASA’s Aug. 19 release, the agency contracted Katalyst Space of Flagstaff, Arizona, to build a robotic servicing spacecraft in less than a year.

NASA’s lessons-learned article describes the compression: the agency had only a few months to issue a call for proposals and fund design studies, and Katalyst then had about a year to design, build, test and launch a satellite that could meet, grab and lift Swift. LINK went through thermal and vacuum testing at Goddard on April 28, 2026, with engineers firing its ion thrusters and operating its robotic arm. It launched in July on a Northrop Grumman Pegasus XL rocket from Kwajalein Atoll; the Aug. 19 release gives the date as July 3. SpacePolicyOnline reported on July 29 that NASA viewed the project as a way to demonstrate on-orbit servicing for a modest $30 million, and that Swift, which was not designed to be reboosted, has no grappling fixtures, so LINK carried three grippers to find a safe place to grab it.

The Spin That Ended the Capture Plan

The trouble began after checkout. In a July 29 report, SpacePolicyOnline said Katalyst had disclosed that LINK was in a multi-axis spin that had lasted 72 hours as of July 28, with two of its three reaction wheels non-functional, its reaction control system only partly working and a temporary loss of communications followed by a bus reset.

On Aug. 19, NASA and Katalyst announced that LINK would not capture or boost Swift. NASA Administrator Jared Isaacman said the result was not the outcome NASA had been working toward, but that it does not change why the mission was worth attempting, adding that NASA will apply the lessons from the rendezvous attempt to future missions. Shawn Domagal-Goldman, director of NASA’s Astrophysics Division, called it a high-risk, high-reward effort on an unprecedented timeline. The lessons-learned article says NASA formally ended its involvement in the LINK mission on Sept. 3, and it does not state a root cause for the communications and orientation failures. The same account says Katalyst and NASA agreed to scale the mission back so that LINK would run technology demonstrations of its xenon propulsion system and its three robotic arms for the U.S. commercial servicing industry.

Rendezvous Demonstrations in Place of a Capture

The scale-back left LINK with a different job, and with the capture abandoned, Katalyst ran the spacecraft as a technology demonstration. According to NASA’s Sept. 4 blog post, LINK raised its orbit, aligned with Swift’s, deployed all three robotic arms and fired its three xenon electric thrusters simultaneously. It came within 7.5 to 9 miles (12 to 15 kilometers) of the observatory and photographed it as a streak, and the post says it would make no closer approach. NASA’s lessons-learned article adds that the demonstrations covered the xenon propulsion system and the three arms that were designed to give flexibility in where LINK could safely grapple Swift, and Katalyst’s own estimate in the post was that LINK would deorbit within two to three weeks.

Ghonhee Lee, Katalyst’s chief executive, said in NASA’s account that LINK was built to take on a problem that did not have an easy solution, and that the company went from concept to launching and operating the first commercial space robot in under a year, though not every objective was met.

Swift’s Remaining Altitude

The observatory kept working through the attempt, with a cost. Flight controllers at the Swift Mission Operations Center at Penn State replaced about 25 percent of science targets with drag-minimizing sky positions in December 2025 and switched entirely to that approach by February 2026, so Swift made no pointed science observations from mid-February to late August. John Nousek, the mission director and a Penn State professor of astronomy and astrophysics, said in NASA’s account that the changes “bought valuable time for the boost mission.” The Aug. 28 blog reports the Ultraviolet/Optical and X-ray telescopes were switched back on Aug. 26 after being turned off in February to cut drag. A Sept. 25 post says the Burst Alert Telescope was confirmed calibrated and detecting gamma rays on Sept. 18, and that automated repointing resumed on Sept. 21.

That Sept. 25 post puts Swift about 200 miles (325 kilometers) above Earth and sinking, with the team estimating it will cross the 185-mile (300-kilometer) threshold in early to mid-October, below which NASA says science observations will likely cease.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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