Boeing space plane returning from year-long secret mission
X-37B Orbital Test Vehicle
Credit: US Air Force
The X-37B Orbital Test Vehicle sits on the runway during post-landing operations Dec. 3, 2010, at Vandenberg Air Force Base, Calif. The X-37B conducted on-orbit experiments for more than 220 days during its maiden voyage. It fired its orbital maneuver engine in low-earth orbit to perform an autonomous reentry before landing. (U.S. Air Force photo/Michael Stonecypher)
