NASA Launches a Robot to Rescue Its Falling Swift Telescope
The $30 million mission is the first attempt by a private spacecraft to capture a U.S. government satellite that was never built to be caught.
NASA has a 21-year-old telescope slipping out of the sky, and on Friday it launched a robot to go catch it.
The target is the Neil Gehrels Swift Observatory, a gamma-ray-burst hunter launched in 2004 that circles Earth roughly every 90 minutes. Its orbit has been decaying for years, and lately faster than expected. Recent solar storms have heated and puffed out the upper atmosphere, thickening the thin gas Swift plows through and dragging it down. Left alone, the $250 million observatory would burn up later this year.
The would-be rescuer is a spacecraft called Link, built by the U.S. startup Katalyst Space Technologies. It is small, about 880 pounds and five feet tall, with three robotic arms that each end in a pair of pinching "fingers." NASA and its partners put it into orbit from the belly of a modified Lockheed L-1011 airliner nicknamed Stargazer, which climbed to about 40,000 feet over the Marshall Islands before releasing a Northrop Grumman Pegasus XL rocket that carried Link the rest of the way. Blast-off came at 0836 GMT on Friday, after weather and technical trouble pushed the launch back from Tuesday.
What happens next is the hard part. Link will take about a month to reach Swift, then spend several weeks studying it from close range to find a safe place to grab, because Swift, like most satellites, was never built with a docking port or anything else designed to be caught. Once it has a grip, Link will fire an efficient ion thruster to walk both craft up to an orbit of about 370 miles, comfortably above the lane the International Space Station uses.
That is the real prize. Space.com notes the mission is a first of its kind: no privately built spacecraft has captured an uncrewed U.S. government satellite before. Get it right and the economics of everything in low Earth orbit start to shift, as a dying satellite becomes a repairable one, a refuelable one, a movable one. Get it wrong, as CNN stresses is entirely possible, and NASA has spent $30 million confirming how hard the problem really is.
Swift has spent two decades catching the universe's most violent flashes, the gamma-ray bursts that mark dying stars and colliding black holes. Whether it gets a few more years now rests on a five-foot robot with a careful grip and a long, slow climb ahead of it.
