It's official: SpaceX has gone where no private company has gone before.

SpaceX's Dragon spacecraft returned to Earth from the International Space Station yesterday, safely splashing down at 12:22 p.m. Pacific time about 250 miles off the coast of southern California. It carried 1,673 pounds of cargo that will be delivered to NASA, including hardware, supplies, and a GLACIER freezer packed with scientific samples.

Founder Elon Musk's commercial space contractor launched an unmanned capsule called Dragon from Cape Canaveral on Oct. 7. Three days later, the craft docked with the International Space Station.

Yesterday, it splashed down in the Pacific Ocean. Dragon's flight marks the first time a private contractor has taken primary responsibility for a mission that in years past would have been managed entirely by NASA.

This mission is the first of at least 12 to the International Space Station that SpaceX will fly under NASA's Commercial Resupply Services contract.

In proving itself a suitable cargo substitute for the now defunct-Space Shuttle, privately held SpaceX is occupying a niche that might have been otherwise filled by the United Launch Alliance jointly operated by Boeing (NYSE:BA) and Lockheed Martin (NYSE:LMT).

Musk founded SpaceX in 2002 . A year later, he teamed with four other entrepreneurs to launch electric carmaker Tesla Motors (NASDAQ:TSLA).