来自MSN7 小时
U.S. Air Force's X-37B shuttle tests secret space maneuvers
The unmanned X-37B shuttle, owned by the U.S. Air Force, has been in orbit for over a year. Although the tests conducted are ...
来自MSN10 小时
X-37B spaceplane tests fuel-saving maneuvers in orbit
The unmanned X-37B spaceplane, operated by the United States Air Force, has been in orbit for over a year. Although the tests ...