Discovery, the world's most traveled spaceship, thundered into orbit for the final time Thursday, heading toward the International Space Station on a journey that marks the beginning of the end of the shuttle era.
The six astronauts on board, all experienced space fliers, were thrilled to be on their way after a delay of nearly four months for fuel tank repairs. But it puts Discovery on the cusp of retirement when it returns in 11 days and eventually heads to a museum.
Discovery is the oldest of NASA's three surviving space shuttles and the first to be decommissioned this year. Two missions remain, first by Atlantis and then Endeavour, to end the 30-year program.
Launch director Mike Leinbach anticipated it would be "tough" to see Discovery take off for the 39th and final time, and even harder when it returns March 7.
"It's a very, very personal thing that we love to do," Leinbach explained. "It's a lot more than just our livelihood. It gets in our soul."