A private company is on the verge of making history by launching a spacecraft to the International Space Station.
An unmanned Falcon 9 rocket belonging to the company known as SpaceX was set to blast off at 4:55 a.m. EDT Saturday. Forecasters put the odds of good weather at 70 percent. A thunderstorm was reported to the south but was expected to move offshore.
The Falcon holds a capsule called Dragon that is loaded with 1,000 pounds of space station provisions.
"Next time Dragon sees the sun, it should be doing 17,000 mph over the Atlantic," SpaceX chief executive officer Elon Musk said via Twitter as the countdown entered the final hours.
A Saturday launch would put the Dragon in the vicinity of the space station on Monday for a series of practice maneuvers, with the actual docking taking place Tuesday. Only governments have accomplished that to date.
NASA is looking to the private sector to take over flights to orbit in the post-shuttle era. The goal is to get American astronauts launching again from U.S. soil. SpaceX officials said that could happen in as little as three years, possibly four. Several other companies are in the running.
SpaceX - or Space Exploration Technologies Corp. - is based in Southern California. That's where the company's Mission Control is located for this flight and where Musk positioned himself for Saturday's launch attempt.
Musk, a co-creator of PayPal, founded SpaceX a decade ago.
About 1,000 SpaceX and NASA guests poured into the launching area in the wee hours of Saturday, hoping to see firsthand the start of this new commercial era. The company had a single second to get its rocket flying.
Everyone, it seemed, was rooting for a successful flight.
"Go SpaceX," read the sign outside Cape Canaveral City Hall. Until NASA's space shuttles retired last summer, the sign had urged on the launches of Discovery, Endeavour and, finally, Atlantis. Those ships are now relegated to museums.
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More information: SpaceX: http://www.spacex.com