The world's first commercial spacecraft has arrived at the International Space Station (ISS), the climax of its landmark mission.
"It looks like we got us a Dragon by the tail," said US astronaut Don Pettit, who was operating the robotic arm from the ISS as it reached out and hooked on to the SpaceX Dragon capsule.
The two spacecraft were travelling about 402 kilometres (250 miles) above northwest Australia at the time of the grab, Nasa said.
With no humans on board, the capsule is delivering about a half ton of supplies and science experiments for the space station, and aims to return a slightly larger load of gear to Earth on May 31.
The US space shuttle program ended last year, leaving only the space agencies of Russia, Japan and Europe capable of cargo missions to service the \$100bn (£63bn) space station.
Nasa is handing over routine orbital flights to private business so it can concentrate on grander destinations like asteroids and Mars.
The California-based SpaceX company is leading the charge under billionaire Elon Musk, who helped create PayPal.
The Dragon's flight has been near flawless since its blast off from Cape Canaveral in Florida on Tuesday, Nasa said.
"Once again SpaceX has done it. They have just become the first private company to successfully launch their own spacecraft and get captured by the International Space Station robotic arm," said a Nasa commentator.
SpaceX lead mission director John Couluris said: "After this mission we are on contract for at least 12 more missions to the International Space Station.
"So we are looking to provide regular services... at a faster rate than some of the other vehicles."
The dragon's historic landing marks the beginning of what Nasa and the White House hope will be a "new era" of spaceflight.
Commercial space ventures are crucial to US President Barack Obama's strategy for Nasa as they enable the agency to concentrate on their grander ventures.
SpaceX hopes the Dragon capsule will be able to carry astronauts in around three years - currently, only Russia can ferry humans to the space station.
Earlier this week, Mr Musk - who is thought to have invested \$100m (£64m) of his fortune in SpaceX - admitted on Twitter that he had almost missed a phone call from Mr Obama.
"The President just called to say congrats. Caller ID was blocked, so at first I thought it was a telemarketer :)," he wrote.