The LINK servicing spacecraft developed attitude-control failures that caused it to spin; NASA says two of three reaction wheels are inoperable and the cold-gas thruster system is partially degraded. Teams plan to stop the spin using electric-propulsion thrusters while Katalyst and NASA remap actuators, retune control algorithms and validate a new attitude controller in simulation. The anomaly delays LINK’s approach to Swift until late August; the $30 million mission must finish by year-end to prevent the telescope’s uncontrolled reentry. Rescuing Swift would extend its life for continued multi-wavelength astrophysics observations.
NASA’s Swift Rescue Mission Hit by Major Setback After LINK Spacecraft Loses Attitude Control
NASA's mission to save the Swift telescope experiences a major setback
The mission to prevent the Neil Gehrels Swift Observatory from decaying into Earth’s atmosphere suffered a significant setback over the weekend when the servicing spacecraft LINK developed attitude-control problems and began to spin.
What happened: NASA reported that two of LINK’s three reaction wheels are currently inoperable and that the spacecraft’s cold-gas thruster system has lost some functionality. Despite these failures, LINK retains power and intermittent communications with the Katalyst operations team.
Immediate response: Teams plan to use LINK’s electric-propulsion thrusters over the next several days to arrest the spin. Katalyst is working closely with NASA to develop and validate a revised attitude controller tailored to LINK’s degraded actuator set. That work includes remapping available actuators, retuning control algorithms and running simulations to validate the updated controller before deploying it in orbit.
Timeline and impact: The anomaly has delayed the mission: LINK is now expected to approach Swift by the end of August, later than originally planned. The servicing mission, launched on July 3 aboard a Northrop Grumman Pegasus XL rocket from Kwajalein Atoll in the Marshall Islands, carries an approximate $30 million budget and must be completed by the end of the year. If Swift’s orbit decays too far, NASA will lose the ability to raise it and the telescope could ultimately reenter Earth’s atmosphere.
Why it matters: The Neil Gehrels Swift Observatory is a multi-wavelength astrophysics platform that observes in visible, ultraviolet, X-ray and gamma-ray bands. It has been crucial for studying gamma-ray bursts, black holes and other transient cosmic events. Successfully rescuing Swift would extend its operational life and allow continued observations of high-priority astrophysical targets.
Next steps: Teams are focused on stabilizing LINK, restoring core systems and validating the updated attitude controller in simulation. Katalyst said the rendezvous and servicing operations will begin once recovery is complete.
Katalyst: “We’re focused on stabilizing the spacecraft and restoring core system functionality while planning rendezvous with Swift, which we will begin executing once recovery is complete.”
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