The team behind the LightSail, a solar-sail based craft currently in orbit after a successful launch last week, is currently wrestling with a software glitch that has rendered the vehicle silent. Its only hope? A stray charged particle.
The Linux-powered LightSail was performing swimmingly until 22 May, when it sent its last data packet to teams based at the California Polytechnic State University and the Georgia Institute of Technology. According to The Planetary Society's Jason Davis, the LightSail's onboard systems have "frozen", thanks to a bug in the way it saves telemetry data:
Every 15 seconds, LightSail transmits a telemetry beacon packet. The software controlling the main system board writes corresponding information to a file called beacon.csv ... As more beacons are transmitted, the file grows in size. When it reaches 32 megabytes ... it can crash the flight system.
The post mentions the bug was fixed in a "later software revision", unfortunately, the LightSail had not received the update at the time of launch. A fix was prepared, but the team wasn't able to upload it in time.
After a few failed attempts to remotely reboot the system, there's no option left by to turn it off and on again, to quote the wise words of the IT Crowd's Roy Trenneman. The bad news is the only way this is going to happen is if a charged particle hits the vehicle's hardware in just the right place.
On the bright side, this is apparently "not an uncommon occurrence":
Cal Poly's experience with CubeSats suggest most experience a reboot in the first three weeks; I spoke with another CubeSat team that rebooted after six. Coincidentally, this is close to the original 28-day sail deployment timeline.
Fingers crossed I guess!