The flight of the LightSail, developed by the non-profit The Planetary Society, is now over. The craft reentered Earth’s atmosphere yesterday and burned up during reentry. The trip, although lasting only 25 days. did end in success, though the flight was not without troubles. The goal of this flight was to simply deploy the sails and prove that the craft was spaceworthy. The next challenge will come late next year when a sister vessel will attempt to ‘fly’ with the sails. The 2016 flight will be partially funded by kickstarter with 9 days left on the project. The goal was to raise $200,000. Currently they have pledges for $903,224.
The craft was inspired by ideas from astronomer Carl Saga. Instead of chemical propellants, it will use the ‘pressure’ of photons on the large sails. In fact it will use the force of protons from the sun much in the same way a sailing ship uses the wind. Granted that the force exerted on the sails will be low, about 5 newtons, but there is no mass or space required for fuel storage. Further, craft using the light sails can maintain the force from the sun over long periods, slowly building up substantial speeds.
Photos sent back from LightSail on June 7 showed that the sails had been successfully deployed.