On June 25th, SpaceX's heavy Falcon Heavy launcher made the third flight in its history with six radio occultation satellites and 18 small satellites on board at different altitudes. Among them, the LightSail 2 demonstrator of the Planetary Society.
LightSail 2 is a 5 kg CubeSat 3U (11.3 x 11.3 x 48.7 cm) with a 4.5 micrometer thick solar sail made of reflective Mylar polymer and covering an area of 32 m² when is deployed. For its orbit deployment that took place a week after launch, LightSail 2 was in the Prox-1 satellite. The solar sail was deployed on July 23rd.
The US nonprofit organization announces success for the LightSail 2 project, which has been crowdfunded. " Over the past four days, the spacecraft has climbed to orbit, or apogee, about 2 km ", wrote the Planetary Society.
" The perigee, or low point of its orbit, has dropped to a similar level, which is in line with pre-flight expectations for the effects of atmospheric drag on the craft. The mission team confirmed that the increase in the climax can only be attributed to the solar sail. "
The main objective of the mission was therefore achieved, namely the demonstration of a propulsion in Earth orbit using a solar sail (and the photons of the Sun).
– Planetary Society (@exploreplanets) July 31, 2019
" Our criterion was to demonstrate controlled solar navigation in a CubeSat by modifying the spacecraft's orbit using only the slight pressure of the Sun, which has never been done before. I am extremely proud of this team. The road was long and we did it "says Bruce Betts of the Planetary Society.
The collected data will be shared with NASA. The US space agency aims to launch a CubeSat 6U as part of the NEA Scout project (Near-Earth Asteroid Scout) with an 85 m² solar sail that will be deployed to adapt its trajectory to the flyover of a near-Earth asteroid.
NB: A solar sail had already successfully flown with the Japanese demonstrator Ikaros in 2010. With LightSail 2, it is a first solar navigation to propel itself into Earth orbit.