Students, faculty and onlookers watch as the space shuttle Endeavour flies over the University of Arizona campus in honor of former Congresswoman Gabrielle Giffords and her astronaut husband Mark Kelly, both of whom watched the event from a private viewing area, before continuing its trek west to retirement in a Los Angeles museum, at the University of Arizona Thursday, Sept. 20, 2012, in Tucson, Ariz.(AP Photo/Ross D. Franklin)