A privately owned rocket was poised to blast off Sunday night on the first of a dozen space station supply missions under a mega-contract with NASA.
It will be the second time that the California-based SpaceX company tries to launch a Dragon capsule to the International Space Station.
Last May, a test flight went well. Now the real work is about to begin under a $1.6 billion contract between NASA and SpaceX. This will be the first of 12 resupply missions under that contract.
"Are you ready to hear the (hash)Dragon roar!" SpaceX said in a Twitter update.
SpaceX raised the Falcon rocket, vertically, at its launch pad Sunday afternoon in advance of the 8:25 p.m. (0025 GMT) liftoff. Forecasters said there's a 40 percent chance that storm clouds or rain could interfere. The good news was that a piece of space junk was no longer threatening the orbiting lab, and NASA could focus entirely on the delivery mission.
NASA is counting on private business to restock the space station, now that the shuttles have retired to museums.
This newest Dragon will carry up about 1,000 pounds (453 kilograms) of food, clothes, experiments and equipment. The three space station residents will get a frozen treat when the capsule arrives later in the week: chocolate vanilla swirl ice cream.
Even more cargo will come back when the Dragon parachutes into the Pacific at the end of October.
None of the Russian, European or Japanese cargo ships can bring anything back; they're destroyed during re-entry.
Space Exploration Technologies Corp., or SpaceX—owned by PayPal co-founder Elon Musk—is working to convert its unmanned Dragon capsules into vessels that could carry astronauts to the space station in three years. Other U.S. companies also are vying to carry crews. Americans must ride Russian rockets to orbit in the meantime, for a steep price.
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