Elon Musk's SpaceX successfully launched a rocket from Cape Canaveral, Fla., on Friday at 4:43 p.m. EDT. The mission, officially known as CRS-8, is the company's eighth cargo resupply mission to the International Space Station. The launch itself was largely routine for SpaceX: the real excitement began when the Falcon 9 completed its burn and landed upright on the drone ship for the first time.
This was the fifth attempt to recover the rocket's first stage on a drone ship—cheekily named Of Course I Still Love You—in the Atlantic Ocean. The company webcasts each of its launches, and young engineers provide running commentary. This time, however, the screams of joy in Hawthorne, California overrode the commentary.
SpaceX made history in December by successfully landing the first stage on land but had yet to complete the same goal on a ship bobbing in the ocean. Reusable rockets that land themselves—unlike the traditional model in which the rocket is left to burn up on reentry—are a critical aspect of reducing the cost to reach orbit. Musk has said that a fully and rapidly reusable rocket is the only way to enable humans to travel to and from Mars.
SpaceX's Falcon 9 rocket and Dragon cargo capsule will carry 7,000 pounds of supplies, science experiments, and technology demonstrations to the orbiting lab, according to NASA. The launch marks SpaceX's first mission to the ISS since last June, when Falcon 9 blew apart 139 seconds after launch. An initial investigation into that mishap pointed to a two-foot-long, inch-thick strut in a liquid oxygen tank that snapped.
SpaceX has said it expects to complete 18 launches in 2016, an ambitious target for a company that flew just six times last year.