Landsat-7 is in trouble. Some 438 miles above, the minivan-sized craft zips around Earth every 16 days. And for over 18 years, the satellite has captured pictures of our ever-changing planet. But Landsat-7 is running out of fuel. If it were an Earth-bound craft, this wouldn’t be an issue. We refuel everything; planes, trains and automobiles.
But up in space, it’s a different story. Satellites toil away hundreds or even thousands of miles from Earth, speeding along at thousands of miles per hour. This speed and distance leaves ground operators largely helpless if anything goes awry. That includes refueling: Once satellites run out of gas, they’re given up for dead. The only exceptions are Hubble and the International Space Station, both of which are in low enough orbit to be reached via shuttle and worth sending people for servicing.
But with the average price tag of satellites topping a billion dollars, ditching the crafts once they hit empty is costly. It also contributes to the ever-growing space junk problem: These once-useful man-made objects become potentially deadly hazards in space. “We don’t do it because we like throwing things away, we do it because there isn’t any other option,” says Benjamin Reed, deputy project manager for NASA’s Satellite Servicing Projects Division, a group determined to change the way researchers view satellites.
Housed in a warehouse at Goddard Space Center in Greenbelt Maryland, the Satellite Servicing Projects Division is working toward revolutionary new technologies that would make it possible to repair, refuel and upgrade satellites while in orbit. Until now, computing power and robotics technology haven’t been sophisticated enough to make this tricky endeavour possible.
The walls of the cavernous “epicenter” of SSPD, as Reed calls it, are draped in black cloth to mimic the darkness of space during simulation runs. Robotic arms, each five or more feet long, are attached at various angles at every work station in the room. A life-size replica of Landsat-7 sits by the door, and two arms point in opposite directions, frozen mid-gesture in front of the craft.
These arms are part of the development stage for a project dubbed Restore-L—a craft intended to launch into space in the summer of 2020, designed to refuel satellites running on empty. Its first target: Landsat-7.