LightSail may unfurl solar sail Wednesday after restoring contact with Earth

A solar sailing spacecraft that lost touch with Earth soon after launch has phoned home. LightSail is now set to unfurl its solar sails as soon as Wednesday.

Attempt to patch buggy software that disabled communications unsuccessful

CBC News Posted: Jun 01, 2015 1:31 PM EDT | Last Updated: June 1, 2015

The bread-loaf-sized LightSail spacecraft was launched into orbit on May 20, and lost contact with Earth on May 22, due to a software bug. It got back in touch on May 30. (Planetary Society)

A solar sailing spacecraft that lost touch with Earth soon after launch has phoned home.

LightSail is now set to unfurl and begin testing its solar sails as early as Wednesday, says the Planetary Society, the non-profit group behind the project.

Originally, the spacecraft was expected to automatically deploy the solar sails in late June.

The Planetary Society, headed by CEO Bill Nye, best known as the Science Guyfrom his popular TV show, is a space advocacy organization co-founded by the late astronomer Carl Sagan.

Solar sails are designed to capture the momentum from solar energy photons using large mirrored surfaces. (YouTube/Planetary Society)

LightSail is an effort to develop solar sailing, a technology that relies on ultra-thin reflective "sails" to capture the momentum from solar energy photons. The small, continuous acceleration allows a spacecraft propelled by solar sails to reach high speeds over time.

The bread-loaf-sized LightSail spacecraft waslaunched into orbit on May 20, and lost contact with Earth on May 22, due to a software bug that causes the flight system to crash once it collects more than 32 MB of data.

After eight days of silence, the spacecraft got back in touch with ground stations on Earth at 5:21 p.m. ET on Saturday.

The spacecraft is thought to have been rebooted by high-energy particles from space, as hoped.

#LightSail is back on line. A cosmic ray from long, long ago, and far, far away gave us a kick in the circuit board. pic.twitter.com/VleLG29x4z
—@BillNye

After the reboot, the ground control team tried to patch the software bug, but wasn't able to maintain stable enough communications to do so.

As a workaround, the team will be rebooting the spacecraft at least once per day.

Initially, after re-establishing contact with the spacecraft, the Planetary Societyhad planned to deploy the sails as early as Tuesday morning. However, itpostponed the event to allowmore time to test the spacecraft's image capture and download capabilities.

LightSail wasn't launched high enough to escape the Earth's atmospheric drag, but is a test designed to gather data for a 2016 flight in a higher orbit that will demonstrate "true solar sailing." The Planetary Society has acrowdfunding campaignto raise money for that mission.