A tiny solar-sailing spacecraft has gone silent in Earth orbit, apparently victimized by a software glitch.
LightSail, a CubeSat designed and built by the nonprofit Planetary Society, stopped beaming data home on Friday (May 22), just two days after it blasted off along with the United States Air Force's robotic X-37B space plane.
"LightSail is likley now frozen, not unlike the way a desktop computer suddenly stops responding," The Planetary Society's Jason Davis wrote in a mission update Tuesday. [ Photos: Solar Sail Evolution for Space Travel ]
The cause of the problem seems to lie with LightSail's flight software, Davis added. The spacecraft, which is about the size of a loaf of bread, was designed to beam telemetry data home in a "beacon packet" every 15 seconds. As this happens, the software writes corresponding information to an onboard file. "As more beacons are transmitted, the file grows in size," Davis wrote in the update. "When it reaches 32 megabytes — roughly the size of 10 compressed music files — it can crash the flight system. The manufacturer of the avionics board corrected this glitch in later software revisions. But alas, LightSail's software version doesn't include the update."
Engineers have come up with a fix for the software problem, but they're unable to upload the patch to LightSail because the spacecraft is unresponsive at the moment, Davis added. So rebooting the CubeSat appears to be the only way to save it.
LightSail's operators have tried rebooting the craft multiple times since they became aware of the problem, but none of the commands have worked. The team may therefore have to wait for a fast-moving charged particle to strike LightSail's electronics in just the right way, Davis wrote. Such "natural reboots" tend to happen to CubeSats after just a few weeks in orbit, so there's hope for LightSail yet: The spacecraft can likely stay aloft in its current configuration for about six months.