The mission marks a new chapter in America's space program with the first official commercial mission to resupply the space station.

In May, SpaceX successfully completed a demo cargo flight to the space station.

This week's effort is the of the company's four-year, $1.6 billion contract to launch a dozen operational missions to the station.

The Dragon spacecraft is scheduled to spend 18 days attached to the station before returning for a splashdown in the Pacific Ocean off the Southern California coast.

Dragon is scheduled to return a total of 1,673 pounds of used supplies and equipment.