Just shy of a year ago, the U.S. Air Force launched an experimental X-37B space drone on a secret mission to the edge of space. The mission, known as OTV-3, isn't super-duper top secret: after all, there's video of the launch. But it is secret in the sense that no one really knows what the heck the unmanned drone has been doing for the past year as it's circled the planet at low Earth orbit.
The Air Force has at least two of this type of space drone: they're made by Boeing and look a lot like miniature space shuttles. Like the shuttle, the X-37B can land on a runway and be reused. Unlike the shuttle, the space drone can perform this feat by itself. The X-37B in orbit right now is actually on its second trip to space, following on the heels of its earlier trip in 2010. The Air Force's other X-37B went up in 2011 and, after 15 months in space, touched down in California's Vandenberg Air Force Base in June.
So what is the Air Force doing with these fancy space drones? No one really knows. (Well, except those with access to classified material.) But theories abound. Some people think it's a weapon—a bomber or a death ray—but USA Today says that's probably pretty ridiculous. According to Popular Mechanics, the space drone could be acting just like any other drone, except in space.
A group of civilian satellite spotters tracking the second X-37B, which is called OTV-2, have noted that the spaceplane’s orbit takes it over countries including Iran, Afghanistan, and Pakistan. Weeden agrees that whatever secret payload the X-37B is carrying could indeed be used to capture data from those regions.
A March story by NASASpaceflight.com gives a slightly more grounded look at what the Air Force may be up to. Boeing, who makes the drone, was trying to pitch NASA on the idea of using the X-37B as a robotic shuttle to low Earth orbit, NASA Spaceflight says. According to Boeing, the ship could be adapted to work as a shipping container to ferry stuff back and forth to the International Space Station. The company also said that the ship could be modified to fit a team of five to seven people and could even be used some sort of escape pod.
NASA seemingly didn't bite on Boeing's proposal, but it does give us an idea of what the little ship could be capable of.
For now, USA Today reports, the Air Force says that the drone is both a test and a testbed. The idea is to iron out the kinks of a reusable, automated space vehicle and use the ship's storage spaces to test how new sensors and other equipment hold up in the harsh environment of space.
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