The engines of the SpaceX Falcon 9 light but fail to launch from the Cape Canaveral Air Force Station on May 19, 2012 in Titusville, Florida. (Roberto Gonzalez/GETTY IMAGES)

Updated 2:32 p.m. 5/21 - The Associated Press reports that a new launch date has been set for Tuesday at 3:44 a.m.

Updated 8:30 a.m.:

The SpaceX lanch was delayed yet again, this time at the last minute. The launch was aborted at the end of the countdown early Saturday morning, according to the Associated Press, even catching NASA’s seasoned commenter George Diller by surprise:

“Three, two, one, zero and liftoff,” announced commentator George Diller, his voice trailing as the rocket failed to budge. “We’ve had a cutoff. Liftoff did not occur.”

Diller completed the countdown, but SpaceX’s Falcon 9 rocket remained on the launch pad.

SpaceX President Gwynne Shotwell said during a press conference Saturday that “this is not a failure” and that they “aborted on purpose.” Shotwell says May 22 or May 23 are being explored as potential launch dates.

Original Post: The Space Exploration Technologies, or SpaceX, Falcon 9 rocket is scheduled to take off at 4:55 a.m. on Saturday, May 19, on a mision to dock at the International Space Station. The launch has been rescheduled multiple times as scientists at SpaceX and NASA have worked on modifications since the April 30 test launch.

A Kennedy Space Center spokesperson confirmed that the launch is still on schedule and SpaceX chief designer Elon Musk Tweeted a photo of the rocket on the launch pad Friday:

Rocket and spacecraft went vertical on launch pad last night. Liftoff in ~18

— Elon Musk (@elonmusk) May 18, 2012

Get some sleep, and some coffee. Tomorrow’s early morning launch webcast starts at 4:15 AM EST at #DragonLaunch

— SpaceX (@SpaceX) May 18, 2012

The launch will be an historic milestone for NASA and for SpaceX, marking the first attempt to send a privately designed, unmanned spacecraft to the space station.

View Photo Gallery: NASA and a company called SpaceX are getting ready to send a rocket to the international space station, a launch that heralds a new strategy of relying on the private sector to deliver cargo — and eventually crews — into orbit.

View Photo Gallery: As the federal government attempts to cut costs, including at NASA, corporations and private investors are venturing further into the realm of exploration innovation.

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