The Air Force says that the almost one-of-a-kind spacecraft "conducted on-orbit experiments" in the the longest-ever mission for the X-37B program.
But what it's doing up there or for how long -- well, you might glean more from talking to the wall than asking the Air Force about its hush-hush mission.
An Atlas V rocket carrying the unmanned craft, which looks like a miniature space shuttle, has the green light for a planned liftoff Tuesday. Just don't ask what it's up to.
The unmanned spacecraft has been in orbit for more than a year. The Air Force won't say much about its mission, but surely it's more than just a test drive.
Resembling a shrunk-down space shuttle, the Air Force's X-37B returns to Earth from its debut test flight, pointing the way toward cheaper, adaptable--and perhaps military--missions.
The unmanned X-37B Orbital Test Vehicle heads into space on its first mission, as the Air Force scopes out how it might eventually serve "warfighters' needs."
The X-37B -- undertaking its fourth mission -- shared its rocket ride back to space with an experimental LightSail spacecraft provided by the Bill Nye-backed Planetary Society.
The experimental LightSail spacecraft has lost communication with Earth due to a software glitch. So far, attempts to initiate a reboot have been unsuccessful.
Spaceships are great, but to explore the weird world that is Titan, a space sub might make more sense. Fortunately, NASA is already working on a design.
The year gone by brought us more robots, worries about artificial intelligence, and difficult lessons on space travel. The big question: where's it all taking us?