The U.S. military's unmanned X-37B robotic space shuttle returned from orbit at 5:48 a.m. in California (1248 GMT) from a secretive 15-month test flight on Saturday (June 16).<br/> <br />The miniature space plane, also known as Orbital Test Vehicle-2, or OTV-2, touched down at California's Vandenberg Air Force Base, 130 miles (209 kilometers) northwest of Los Angeles.<br/> <br />It was only the second U.S. vehicle to make an autonomous runway landing from space.<br/> <br />The military, which took over the program from NASA, says it is using them to learn how to quickly and inexpensively refurbish reusable spaceships for flight.<br/> <br />It is not known if it carried anything in its cargo bay, which is about the size of a pickup truck bed.<br/> <br />The vehicles look like miniature versions of NASA's now-retired space shuttle orbiters, with a similar shape and a payload bay for cargo and experiments.<br/> <br />The X-37B due to fly this fall is the vehicle that inaugurated the program in 2010.
