NASA's Space shuttle Discovery, atop a modified 747 carrier aircraft, lift off from Edwards Air Force Base, California, September 20, 2009, en route to the Kennedy Space Center in Florida. Discovery had landed at Edwards Air Force Base on September 11 after the STS-128 mission to the International Space Station. Picture taken September 20, 2009. REUTERS/Tony Landis/NASA/Handout (UNITED STATES SCI TECH ENVIRONMENT) FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS