NASA Scraps Swift Telescope Rescue After 9-Degree-per-Second Spin

The Neil Gehrels Swift Observatory launched in 2004. It was built to last two years and kept working for two decades, at a cost of an estimated $500 million. Later this year it will fall back into the atmosphere and burn up.

The rescue plan was simple in concept and brutal in execution. Less than a year ago, NASA awarded Katalyst a $30 million contract to build and launch LINK, a spacecraft about the size of a refrigerator. It carried two solar arrays, three xenon-fueled electric thrusters and three robotic arms meant to grab Swift and push it into a higher orbit. Ars Technica reported that NASA gave Katalyst nine months to design, build and launch. That schedule forced engineers to accept technical risks they would normally turn down.

LINK lifted off on 3 July on a Northrop Grumman Pegasus XL rocket. The first weeks went smoothly. Then it spun out of control. According to NASA, Katalyst engineers had first "addressed early communications and attitude control issues" in a 15 July blog post, but the software patches appear to have failed. By 28 July, NASA said the spacecraft's attitude control systems had malfunctioned, "causing the spacecraft to spin and resulting in sporadic communications." Ars Technica reported that two of the satellite's three reaction wheels stopped working, and that the cold gas thrusters used for finer pointing control were also giving trouble. That left the three low-impulse plasma thrusters as the only way to regain orientation, while LINK raced around Earth at nearly 5 miles per second.

Mission managers did manage to fire the thrusters and slow the spin this month, but the underlying attitude control problems stayed. On Wednesday, NASA and Katalyst agreed to abandon the capture and boost. "Ongoing attitude control issues" will keep LINK from completing its rescue mission, Katalyst said in a statement.

"This is not the outcome we were working toward, but it does not change why this mission was worth attempting," NASA Administrator Jared Isaacman said. "We are going to learn everything we can from LINK's rendezvous attempt and put those lessons to work on the missions that follow."

Katalyst CEO Ghonhee Lee struck a similar tone. "We took on this high-risk, high-reward challenge and are proud of the milestones we reached along the way," Lee said. "We have already learned a tremendous amount, and now our job is to turn those lessons into something durable, building a repeatable playbook to inform future rendezvous and proximity operations and satellite servicing."

The failure leaves a gap in astronomers' ability to study gamma-ray bursts, the most powerful explosions in the universe. Swift combined multi-wavelength instruments with agile pointing, which let it find these bursts and pin down their locations so other observatories could follow up. Without Swift, that capability is unlikely to be replaced anytime soon.

Swift's troubles began in 2024, during a stretch of intense solar activity. Every satellite in low Earth orbit slowly loses altitude to atmospheric drag. When the sun grows more active, it heats Earth's atmosphere, drag increases and orbits decay fast. Swift had no thrusters to hold its orbit, so a rescue mission was the only way to keep it alive. Shawn Domagal-Goldman, who directs NASA's astrophysics division, called it "a first-of-its kind attempt, developed on an unprecedented timeline driven by the Sun's activity."

LINK is not dead yet. Katalyst said it will keep gathering data and may still attempt a rendezvous with Swift to demonstrate close-in navigation technology. According to Ars Technica, the company wants to pull technical and operational value out of the spacecraft. Those lessons could matter as space agencies and private companies chase satellite servicing, a capability that could one day refuel, repair or upgrade orbiting spacecraft.

For Swift, though, the end is close. The observatory is expected to plunge through the atmosphere later this year and break apart on re-entry. "We were all hoping for more science from Swift," Domagal-Goldman said. "But we knew the takeaways from this mission would be worthwhile either way."