SpaceX has obtained approval from the American aviation safety regulatory agency for the fifth major test flight of its giant interstellar spaceship rocket. This is a key mission, with the booster portion returning from space and attempting a vertical landing. The Federal Aviation Administration, responsible for issuing rocket launch and re-entry permits, issued an order on Saturday approving this mission. SpaceX now has permission and plans to launch the interstellar spaceship from the company's launch site in southern Texas on Sunday.