After a mysterious 15 month, 469 day mission the X-37B space plane has returned. Touching down at Vandenberg Air Force Base, California, on a cold Saturday night the X-37B Orbital Test Vehicle 2 (OTV-2) returned to Terra-firma.

When the X-37B was initially launched from Cape Canaveral atop an Atlas rocket the mission was intended to last only 9 months. Not that any information was available on the original mission objectives. When the mission was extended for an unknown period, 6 months as it turns out, the rumour mill started churning at an even faster rate.

There are currently two X-37B’s in testing, OTV-1 and OTV-2, usually one is in the workshop while the other is in orbit.

The X-37B was originally designed as a portable toolbox for the space shuttle, with the dimensions designed to allow it to fit snugly in the shuttles pay load bay. When the shuttle was retired the X-37B stepped up to the mark.

“With the retirement of the Space Shuttle fleet, the X-37B OTV program brings a singular capability to space technology development,” said Lt Col Tom McIntyre, the X-37B’s programme manager.

He continues “The return capability allows the Air Force to test new technologies without the same risk commitment faced by other programs. We’re proud of the entire team’s successful efforts to bring this mission to an outstanding conclusion.”

The mystery of the X-37B is only heightened by the fact that the missions undertaken by the little space plane are completely secret. All missions are described as space based testing of equipment.

As with all mysteries the space between known facts is quickly filled in with speculation. There are many rumours relating to the X-37B’s activities while in space. Obviously the standard line from NASA is a partial truth, they are testing new hardware in space, the X-37B itself falls into this category. What hardware it is carrying into space for testing is the million dollar question. What secret hardware does the pickup sized payload bay carry?

Mission speculation includes spying on the Chinese as they make the move into space, trips to the moon have also been rumoured as has testing new Earth facing camera equipment for reconnaissance. Weapons testing is one of the most controversial potential missions, space is the next frontier and the X-37B is partially funded and operated by NASA and the US Air Force.

There is no rest for the X-37B’s a new mission has been announced, this time OTV-1 will be sent into orbit at the end of 2012. Once again the mission is classified.

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