NASA’s attempt to extend the life of the falling Neil Gehrels Swift Observatory has suffered a setback after its rescue spacecraft, LINK, began spinning uncontrollably in orbit. The problem puts the mission’s outcome in doubt, as LINK must be stabilised and reconfigured before it can attempt to dock with Swift and raise it to a safer orbit.

LINK has lost the use of two of its three reaction wheels and has reduced cold-gas thruster capability, causing intermittent communications, though ground controllers remain in contact. NASA and Katalyst Space plan to use the craft’s electric thrusters to halt the spin, then reassess whether it can still rendezvous with Swift, which is expected to re-enter Earth’s atmosphere this year without intervention because increased solar activity has accelerated its orbital decay.