A mission to save NASA’s falling observatory spun out of control. What happens next

LINK Spacecraft Faces Spin Crisis While Racing to Save Swift Observatory

Healfromzero.com – A critical rescue operation for one of NASA’s most valuable space telescopes has encountered unexpected complications, though mission controllers remain optimistic about salvaging both spacecraft. The Neil Gehrels Swift Observatory, which has been monitoring the cosmos from low-Earth orbit for approximately two decades, now depends on a newly deployed satellite to prevent an untimely descent into Earth’s atmosphere.

Swift’s Long Service and Growing Vulnerability

Since its launch nearly twenty-two years ago, Swift has functioned as a versatile astrophysics instrument capable of detecting and tracking celestial explosions across the universe. The observatory serves as NASA’s rapid-response capability when stars, black holes, and other cosmic phenomena suddenly brighten or emit intense radiation. However, increasing solar activity has strengthened atmospheric drag on the satellite, gradually pulling it toward a lower orbit. Without corrective action, Swift faces reentry sometime this autumn once it drops beneath approximately 185 miles, or 300 kilometers, above Earth’s surface. This altitude threshold represents the minimum height needed to maintain stable orbital operations.

The LINK Rescue Mission

Katalyst Space Technologies, an Arizona-based company, received a challenging assignment: design, construct, test, and deploy a spacecraft capable of reaching Swift and elevating its orbit. The company accomplished this ambitious timeline in just nine months. The resulting satellite, designated LINK, lifted off on July 3 aboard a Northrop Grumman Pegasus XL rocket. This rocket was carried aloft by Stargazer, a specially modified L-1011 aircraft that releases payloads mid-flight.

Initial Success Followed by Complications

Everything proceeded smoothly following LINK’s deployment until approximately July 25, when the spacecraft began rotating uncontrollably in space. This uncontrolled spinning temporarily disrupted communications between LINK and ground controllers. Mission teams from both Katalyst and NASA confirmed the issue on July 28.

Technical Challenges and Recovery Efforts

Investigations revealed that two of LINK’s three reaction wheels—devices that help stabilize spacecraft orientation—had ceased functioning. Additionally, the satellite’s cold gas thruster system experienced partial failures. These combined issues caused LINK to enter a multi-axis spin lasting several days.

Progressive Stabilization

Katalyst engineers implemented a series of thruster burns to gradually reduce the rotation. The spin rate dropped from roughly 9 degrees per second down to 4 degrees per second within two days. Further adjustments brought the rotation to 1.47 degrees per second, a speed LINK will maintain while teams prepare for the next phase of operations.

Restoring Mission Capabilities

The team utilized one of LINK’s electric propulsion thrusters to slow the spacecraft’s rotation. Engineers also deployed flight software patches and operational updates to address early communications and attitude control problems. These modifications restored reliable communication links and improved the satellite’s ability to maintain proper orientation.

Looking Ahead

While LINK’s spin is now largely manageable, the rendezvous with Swift faces delays. Mission planners are developing innovative approaches to ensure the rescue satellite reaches the observatory before atmospheric drag becomes insurmountable.

I think one of the difficult things to convey is how amazing it is that we’ve gotten this far. Even if everyone does everything perfectly, there still might be risks that we cannot control ahead of us. I’m just deeply thankful that we’re even giving this a go.

— Shawn Domagal-Goldman, NASA division director of astrophysics

What Happens Next

LINK will continue validating its performance while preparing for extended thruster burns required during the grappling operation. The satellite must eventually dock with Swift and fire its engines for multiple hours to raise the observatory’s altitude sufficiently to avoid reentry. If successful, both spacecraft will continue their scientific missions. If the rescue fails, Swift will burn up in Earth’s atmosphere, potentially ending twenty-two years of valuable astronomical observations. Mission teams remain cautiously optimistic that LINK can overcome its current challenges and complete its critical mission.