An unmanned spacecraft that was sent to rescue a falling NASA space telescope now needs an intervention of its own. NASA’s Neil Gehrels Swift Observatory was launched in 2004 to observe gamma-ray bursts, bright flashes of high-energy light from violent explosions throughout the universe. Katalyst was commissioned for a “high-risk, high-reward” effort to rush through a small rescue craft, called Link, to push Swift into a higher orbit. But Link unexpectedly started tumbling just a few miles from Swift, making a full rotation every 40 seconds and putting the rescue mission in danger. Link’s rendezvous with Swift has been delayed by at least a couple of weeks, but NASA said the agency was hopeful they would find a solution.