NASA awarded one of two contracts to deliver cargo to the International Space Station to Space Exploration Technologies, the fledgling company Pay Pal Inc. co-founder Elon Musk started six years ago.

The contracts, worth a combined $3.5 billion US, were awarded Tuesday to Hawthorne, Calif.-based Space Exploration Technologies, or SpaceX, and Dulles, Va.-based Orbital Sciences Corp.

The two private companies will be tasked with delivering supplies to the orbital outpost after the U.S. shuttle fleet is retired in 2010, NASA said Tuesday.

SpaceX's contract is for 12 flights at a price of $1.6 billion US, while Orbital will make up to eight flights for $1.9 billion US. The contracts call for a minimum of 20 tonnes in cargo mass to be delivered to the space station.

SpaceX and Orbital won the contracts over a third bidder, a consortium called PlanetSpace that included three NASA prime contractors — Lockheed Martin, Boeing and Alliant Techsystems.

SpaceX is a new player to the space exploration industry, and only this year completed its first successful launch of a commercial rocket, the Falcon 1, the first in a family of low-cost launch vehicles priced at $7.9 million US each. The company is expected to make the trips to the space station with another rocket, called the Falcon 9.

Orbital is a more established company, and may be familiar to Canadians as the owner, for a brief time, of the Canadarm technology. Orbital was the majority owner of MacDonald, Dettwiler and Associates Ltd. when it purchased Spar Aerospace Ltd.'s space robotics business in 1999. Orbital divested itself of MDA in 2001.