Just days after aborting a rocket launch at the last second because of an engine problem, SpaceX is once again set to blast off from Cape Canaveral, Fla., in hopes of becoming the first private company to visit the International Space Station.
The company, formally known as Space Exploration Technologies Corp., first set out to launch on Saturday at 4:55 a.m. EDT. The countdown was flawless until the last second, when the rocket engines briefly lit up and then went dark.
SpaceX said a flight computer detected an anomaly in one of its rocket's nine engines and automatically shut down the launch sequence.
"During rigorous inspections of the engine, SpaceX engineers discovered a faulty check valve on the Merlin engine," said SpaceX spokeswoman Kirstin Brost Grantham in a statement. "The failed valve was replaced on Saturday and after thorough analysis the vehicle has been cleared for launch."
The launch is now set for 3:44 a.m. EDT Tuesday and will be webcast on SpaceX's website as well as NASA TV. The blast-off is a much-anticipated test of NASA's plan to outsource space missions to privately funded companies.
SpaceX has had two successful launches of its Falcon 9 rocket. The most recent blast-off was in December 2010 when SpaceX became the first private company to send a spacecraft into orbit and return it intact.
The company, based in Hawthorne with about 1,800 employees, is launching the rocket carrying its Dragon space capsule in a demonstration for NASA. The unmanned docking mission to the space station is intended to prove that SpaceX's rocket and capsule are ready to take on the task of hauling cargo for the space agency now that the space shuttle fleet has been retired.
SpaceX has a $1.6-billion contract to haul cargo in 12 flights to the space station for NASA.
Even though the upcoming mission is a test flight, the Dragon capsule is carrying about half a ton of food and other supplies for the crew aboard the station.
The capsule is supposed to dock with the space station three days after launch. If the mission is successful, it will mark the first time that a privately built craft has docked with the $100-billion orbiting outpost.
Sending a spacecraft to the space station has been accomplished only by four of the world's wealthiest and most technologically advanced nations: the United States, Russia, Japan and the European Union.
SpaceX makes its Dragon capsule and Falcon 9 rocket at a sprawling facility in Hawthorne that once was used to assemble fuselage sections for Boeing 747s. The hardware is put on a big rig and trucked to Cape Canaveral for launches.
If the launch, which has been delayed several times already, does not happen Tuesday morning, SpaceX has an open launch window on Wednesday at 3:22 a.m. EDT.
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