The mysterious unmanned mini-space shuttle on a classified mission has finally returned to earth. It landed early Saturday morning at Vandenberg Air Force Base in California at 5:48 a.m. PDT after weather conditions kept pushing back landing attempts the last few days. The shuttle spent 469 days in orbit.

The Air Force's X-37B, is an unmanned reusable spacecraft built by Boeing that has spent more than a year on a classified mission in space.

Measuring 29 feet in length and having a 15-foot wingspan, the unmanned reusable X-37B Orbital Test Vehicle looks like a miniature version of NASA's now retired space shuttles.

The craft went into orbit on March 5, 2011, but as was the case during its first launch in 2010, very little has been known about its mission or what payloads it might be carrying because its missions are classified.

That has led to speculation that the spacecraft is involved in intelligence gathering operations or the testing of new technologies.