That mysterious robotic spaceship that the U.S. Air Force sent into orbit for seven straight months last year may get a bit of an upgrade. Boeing is toying with the idea of expanding the X-37B into the X-37C, which could carry up to six astronauts into space and back. We could be looking at the next generation of space shuttle.

Nobody's really sure what the X-37B is for. All we know is that the Air Force sent it up into space, twice, and it stayed there for a long time (months), changing orbits and doing mysterious (and highly classified) things. Evidently it did what it was supposed to do, and did it well enough that the Air Force asked Boeing to build it a second one.

For its part, Boeing is looking even farther ahead, and they've drafted designs for an X-37C, which would be just like the X-37B, only about twice the size. This would make it large enough to carry a six person crew capsule in the cargo bay, or in a slightly different configuration, give it a space shuttle-style cockpit and crew area.

While the X-37C might offer many of the same capabilities as the space shuttle (albeit in a much smaller package with a reduced cargo capacity), it would be cheaper, with a faster turnaround, and would launch on top of a rocket system (the Atlas V) that could be used for other cargo, making it much more versatile:

So what are the odds of this actually happening? Well, there's a notable gap in the U.S. space program, seeing as we're having to rent Russian capsules to get our astronauts into orbit, but from the sound of things, NASA would rather invest in private industry than attempt to support another reusable space vehicle. The fact that this is an Air Force project, though, does put it into a bit of a gray area, and it's entirely possible that the military and Boeing could get together and make something happen.

Space.com, via Danger Room