This undated file image provided by the U.S. Air Force shows the X-37B spacecraft. The unmanned Air Force space plane steered itself to a landing early Saturday, June 16, 2012, at a California ... more 
This undated file image provided by the U.S. Air Force shows the X-37B spacecraft. The unmanned Air Force space plane steered itself to a landing early Saturday, June 16, 2012, at a California military base, capping a 15-month clandestine mission. (AP Photo/U.S. Air Force, File) less 
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Associated Press | Photo By U.S. Air Force, File
Sat, Jun 16, 2012 11:39 AM EDT