A new way to travel space: LightSail, solar sail project from The Planetary Society, crowdfunded by 23,331 Kickstarter backers, becomed the first spacecraft in Earth orbit propelled solely by sunlight, and that raised its orbit with solar sailing. Deployed from the Prox-1 CubeSat. To measure change in orbit due to solar sailing, LightSail 2 had a small cluster of mirrors on the bottom of CubeSat allowing lasers on the ground to precisely measure the spacecraft's orbit. The lightsail was deployed successfully on July 23, 2019.