The minuscule but revolutionary LightSail 2 spacecraft that uses the pressure from sunlight to propel it through the void of space contacted its controllers at the Planetary Society on Tuesday.
The spacecraft's calling home sets the stage for the most exciting and critical part of its spaceflight -- unfurling its kite-shaped Mylar solar sail with a total area of 32 square meters (340 sq ft), about the size of a boxing ring. This is expected to take place on July 10.
The Planetary Society, an American non-profit foundation devoted to space exploration, said LightSail 2 will demonstrate controlled solar sailing in low Earth orbit (LEO). The spacecraft's flight team will attempt to raise the orbit apogee (the farthest orbit) and increase orbital energy following sail deployment.
The LightSail 2 spacecraft's core measures 10 cm × 10 cm × 30 cm (or a 3U CubeSat). It launched as a secondary payload on the Space Test Program (STP-2) mission on a SpaceX Falcon Heavy rocket on June 25. LightSail 2 was deployed into LEO by the Georgia Tech Prox-1 carrier satellite.
After deploying from its spring-loaded enclosure known as a P-POD, LightSail 2 deployed its radio antenna and began transmitting health and status data on July 2, as well as a morse code beacon indicating its call sign.
The thin and lightweight sail will propel LightSail 2 forward as it raises its orbit from its current 720 km above the Earth's surface. Powering the spacecraft's flight will be the force generated by photons produced by sunlight as they hit the sail.
Once it succeeds in deploying its sail, LightSail 2 will be the first Earth spacecraft to travel through space using the power of sunlight alone.
LightSail 2 will have to perform on-orbit test operations before deploying its sail. These operations include a health check, radio communication with terrestrial ground stations and photographic test images.
After the solar panel deployment will follow operational light sail testing that will include raising the apogee and lowering the perigee of LightSail 2. These operations are expected to last a month.
"We're all very happy -- after years of preparation, we are flying an operational spacecraft!" said Bruce Betts, LightSail program manager, and Planetary Society chief scientist.
LightSail 2 is a citizen-funded project to send a small spacecraft, propelled solely by sunlight to Earth orbit.
