Liftoff of the Falcon 9 rocket, its Dragon capsule filled with food, supplies and science experiments, had been scheduled for 4:55 a.m.

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The flight will be scrubbed for at least three days if the company's 18-story Falcon 9 rocket and teardrop-shaped Dragon capsule aren't ready.

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The company successfully developed its own launch vehicle, the Falcon 9 rocket, and its own spacecraft, called the Dragon.

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The Sunday flight -- dubbed CRS-1 -- will have the Dragon capsule piggybacking on a Falcon 9 rocket to punch through the atmosphere while carrying more than a thousand pounds of cargo.

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