The private spaceflight company SpaceX has officially set Friday as the target date for the launch debut of its new Falcon 9 rocket.
The new commercial rocket, designed to haul cargo to the International Space Station, may one day also carry astronauts to Earth orbit.
Space Exploration Technologies (SpaceX) of Hawthorne, Calif., planned to roll out Falcon 9 today to its dedicated seaside launch pad at Cape Canaveral Air Force Station in Florida.
The rocket has a four-hour window in which to launch, starting at 11 a.m. EDT (1500 GMT). If weather or some other obstacle prevents the test from taking place Friday, SpaceX can try again on Saturday.
Both days have about a 60 percent chance of favorable weather, forecasters predict. Cumulus clouds and anvil clouds from thunderstorms could prevent the launch.
The one major hurdle left before the fledgling rocket can attempt to launch is final approval of its flight termination system (FTS), an explosive charge that would destroy the rocket if it flew off course. Both SpaceX and the U.S. air force, which monitors the launch area, must be confident that the system works before Falcon 9 can lift off.
"We are now looking good for final approval of the FTS by this Friday, June 4th, just in time for our first launch attempt," SpaceX officials said in a Tuesday statement.
This test version of Falcon 9 will carry a mockup of SpaceX's Dragon capsule, which is designed to carry cargo, and eventually humans, to the International Space Station. This SPACE.com graphic shows how SpaceX's Falcon 9 and Dragon stack up to other rockets.
NASA has already awarded SpaceX a $1.6 billion contract to use Falcon 9 and Dragon to haul cargo to the station starting in 2011. If all goes well on the first test launch, real cargo will fly atop the second Falcon 9 flight, the company has said.
This test launch has been held up by the approval process and by a crowded range. The successful launch May 27 of a GPS satellite cleared up a window for SpaceX to proceed.
The company said its expectations are not set too high for this first effort to run through a complete countdown and launch of the 178-foot (54-meter) tall rocket.
"Since this is a test launch, our primary goal is to collect as much data as possible, with success being measured as a percentage of how many flight milestones we are able to complete in this first attempt," SpaceX said in the statement. "It would be a great day if we reach orbital velocity, but still a good day if the first stage functions correctly, even if the second stage malfunctions. It would be a bad day if something happens on the launch pad itself and we're not able to gain any flight data."
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