Despite budget uncertainties, NASA on Thursday announced plans to send the space shuttle Atlantis on the final mission of the US program June 28, after which the famed fleet will be retired.
"It is NASA's intent to fly the mission with orbiter Atlantis carrying the Raffaello multipurpose logistics module to deliver supplies, logistics and spare parts to the International Space Station," a statement said.
President Barack Obama has signed a bill authorizing NASA to conduct the third and final mission, but the US space agency's budget for 2011 remains to be approved so the shuttle flight depends on congressional authorization of extra funds.
The Atlantis flight would be the shuttle program's 135th and final mission to space.
The shuttle Discovery is scheduled to launch on February 24 and the shuttle Endeavour is set for takeoff on April 19.
The US program got its start when the shuttle Columbia roared into space on April 12, 1981.
The shuttle Enterprise, a prototype which was never flown into space, is already a museum piece in a hangar outside Washington.
The other two shuttles of the original fleet were destroyed in explosions; Columbia upon re-entry from orbit in 2003 and Challenger shortly after liftoff in 1986.
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