The Planetary Society today confirmed that its LightSail satellite has successfully deployed its Mylar solar sail, achieving the main objective of the mission after 19 days in low-Earth orbit. The CubeSat, which is about the size of a loaf of bread, completed transmission of its first image to a ground station at Poly San Luis Obispo in California, showing the sail open and partly spread out.
Though the deployment wasn't confirmed until today, it actually occurred on June 7. The CubeSat took a self portrait on June 8, which was transmitted to Earth in packets as the satellite passed over a mission ground station.
“This LightSail test taught us a lot, just as we hoped it would, and so we’re ready to do some real solar sailing with LightSail’s 2016 mission,” says Bill Nye, Planetary Society CEO.
Built by Stellar Exploration Inc, LightSail was launched on May 20 from Cape Canaveral Air Force Station as a piggyback cargo atop an Atlas V rocket for the US Air Force's AFSPC-5 mission. Its purpose is to test critical systems for a solar sail system that uses the pressure of sunlight to propel a spacecraft , similar to the way wind propels a sailing ship. Though the pressure of photons striking the sail is almost indiscernible, the fuelless system has the potential of generating remarkably high velocities over time.
Since the launch, LightSail suffered two signal losses and problems with its battery system. At one point, its computer froze and only rebooted because the electronics were struck by cosmic rays.
The Planetary Society says that there are still a number of tasks to carry out before LightSail reenters the Earth’s atmosphere. The spacecraft is downloading a second image and mission engineers hope to extend the sail's spars to flatten it out, so they can look for any sign of tension caused by sunlight pressure.
A second mission is set for 2016. It will be launched to an altitude of 450 mi (720 km) as part of the payload of Virginia Tech's Prox-1 mission, where it will act as a rendezvous target for the Virginia Tech craft for two weeks before carrying out a full demonstration of the light-sail system by using the sail for actual propulsion.
"This week's flight was an ideal test in preparation for our primary mission in 2016. We were able to validate the function of all key spacecraft systems including solar sail deployment, and along the way the team was forced to deal with a number of anomalies and setbacks," says Doug Stetson, LightSail project manager. "We've learned a tremendous amount about our spacecraft and operations plan, and we're already preparing for what should be a spectacular flight late next year."
Source: The Planetary Society