NASA to use Earth as slingshot to propel spacecraft
In a first-of-its-kind mission to bring back asteroid samples, NASA would use Earth as a slingshot for its asteroid-bound spacecraft. The gravity assist would alter OSIRIS-REx mission's trajectory and put it on a course to match asteroid Bennu's path and speed. "At roughly 500 meters in diameter, Bennu will be the smallest object that NASA has orbited," said an official.