SpaceX plans to lay off 10 percent of its more than 6,000 employees, a source familiar with the decision said on Friday. “To continue delivering for our customers and to succeed in developing interplanetary spacecraft and a global space-based Internet, SpaceX must become a leaner company,” the California-based company, headed by Elon Musk, said in a statement to AFP. The announcement came as SpaceX on Friday launched a Falcon 9 rocket from Vandenberg Air Force Base in California carrying 10 communications satellites.