Solar sails into orbit on crowdfunded satellite

The Lightsail 2 mission, a crowdfunded project developed by the U.S.-based Planetary Society, has successfully deployed its solar sail, and sent back dramatic photos from its position in lower-earth orbit.

The solar sail uses sunlight for propulsion: rather than absorbing photons to generate electricity, the light particles are reflected by the boxing ring sized sail, and their momentum is used to push the bread loaf sized satellite through the vacuum of space.

The sail began its journey to space in June 2019, and late last week the first photos of it fully deployed were published by the planetary society. “The successful deployment of the solar sail and the onset of sail control completes our critical post-launch phase,” said LightSail 2 project manager David Spencer. “Now we are prepared for the solar sail's mission, to track how the orbit changes and evaluate solar sailing performance.”

Satellite data is showing it turning its sail toward the sun once per orbit, which gives a very slight push to raise its orbit. The Planetary Society has high hopes for solar sails to be used to propel future space exploration missions, saying that with small amounts of continuous thrust, they are ultimately able to reach higher speeds than chemical powered rockets. The technology could already be viable for use with Cubesats – a small, standardized type of satellite.

The society also notes, however, that the push provided by the sail is “no stronger than the weight of a paperclip.” It will take around one year before the satellite is expected to reenter Earth’s atmosphere.

The Lightsail 2 project was funded with $7 million between March 2009 and March 2019. A 2015 kickstarter campaign raised $1.24 million, and further funding was provided by Planetery Society members and private citizens.