The space shuttle Endeavour, carried atop NASA's 747 Shuttle Carrier Aircraft, passes over petrochemical facilities on the Houston Ship Channel during a flyover on Wednesday, Sept. 19, 2012, in Houston. Endeavour stopped in Houston on its way from the Kennedy Space Center to the California Science Center in Los Angeles, where it will be placed on permanent display. (AP Photo/Houston Chronicle, Smiley N. Pool, Pool)

Photo by: Smiley N. Pool

The space shuttle Endeavour, carried atop NASA's 747 Shuttle Carrier Aircraft, passes over petrochemical facilities on the Houston Ship Channel during a flyover on Wednesday, Sept. 19, 2012, in Houston. Endeavour stopped in Houston on its way from the Kennedy Space Center to the California Science Center in Los Angeles, where it will be placed on permanent display. (AP Photo/Houston Chronicle, Smiley N. Pool, Pool)