Japanese Spacecraft Successfully Deploys Solar Sail in Spac

Japanese Spacecraft Successfully Deploys Solar Sail in Space: "The Japanese spacecraft IKAROS created centrifugal force by spinning, allowing it to launch the .0003-inch-thick sail. While deployment is a challenge in a zero gravity environment, spacecraft — unlike airplanes — don’t have to contend with drag, so with each photon of light that hits the sail, the spacecraft could gather speed. The sail isn’t yet propelling IKAROS; that will be the true measure of the mission’s success."