The LightSail, launched on May 20, has gone silent. LightSail is a CubeSat designed to test solar powered propulsion. 

LightSail was sending data back to Earth every 15 minutes. Before the system froze, LightSail returned more than 140 packets of data. "When it reaches 32 megabytes-roughly the size of ten compressed music files-it can crash the flight system," wrote Jason Davis, digital editor for The Planetary Society.

"Since we can't send anyone into space to reboot LightSail, we may have to wait for the spacecraft to reboot on its own," Davis wrote. "Spacecraft are susceptible to charged particles zipping through deep space, many of which get trapped inside Earth's magnetic field. If one of these particles strikes an electronics component in just the right way, it can cause a reboot. This is not an uncommon occurrence for CubeSats, or even larger spacecraft, for that matter. 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."

From a press release from The Planetary Society:

"After a successful launch into orbit aboard a United Launch Alliance Atlas V rocket out of Cape Canaveral, The Planetary Society's LightSailTM spacecraft went silent after two days of communications. The solar sailing spacecraft test mission, a precursor to a 2016 mission, has been paused while engineers explore a suspected software glitch that is believed to have affected communications. A reboot is necessary to continue the mission. Upon reboot, the LightSail team may initiate manual deployment of the spacecraft's Mylar® solar sails. Bill Nye (The Science Guy), CEO at The Planetary Society, issued the following statement:

'A problem like this teaches you more about your spacecraft than a mission that's trouble-free. This is our test flight, and we have a healthy spacecraft in a stable orbit. Soon, we expect our little LightSail to reboot on its own, and we can get down to business up there. After 39 years, I can hang in for a few more weeks.'"

The Planetary Society was founded in 1980 by Carl Sagan, Bruce Murray and Louis Friedman. 

For more on LightSail, check out this video posted by The Planetary Society: