NASA’s long term orbital drone, the X-37B Orbital Test Vehicle, made an unannounced (at least to the public) landing at NASA’s Kennedy Space Center Shuttle Landing Facility on Saturday.  The unmanned spacecraft that bears a striking resemblance to the now defunct space shuttle, first made its presence known to the community surrounding Kennedy Space Center on Saturday morning as it broke the sound barrier during re-entry, prompting a number of Tweets directed at NASA attempting to determine where, or what, the boom may have come from.

The ship has been in orbit around the earth for a whopping 718 days during this mission, bringing the total number of days the X-37B orbiter program has spent in space up to 2,085 days.

“Today marks an incredibly exciting day for the 45th Space Wing as we continue to break barriers,” said Brig. Gen. Wayne Monteith, the 45th SW commander in a press release. “Our team has been preparing for this event for several years, and I am extremely proud to see our hard work and dedication culminate in today’s safe and successful landing of the X-37B.”

“The landing of OTV-4 marks another success for the X-37B program and the nation,” said Lt. Col. Ron Fehlen, X-37B program manager. “This mission once again set an on-orbit endurance record and marks the vehicle’s first landing in the state of Florida. We are incredibly pleased with the performance of the space vehicle and are excited about the data gathered to support the scientific and space communities. We are extremely proud of the dedication and hard work by the entire team.”

Of course, despite a number of senior officials being happy to describe how proud they are of the X-37B and its most recent set of accomplishments, they remain rather tight-lipped as to just what, exactly, those accomplishments might be.  Despite publicly acknowledging the program, launch and return dates are never announced in advance, nor are any mission details pertaining to just what the X-37B does during its long duration space flights.

All the Air Force is willing to tell us is that it “performs risk reduction, experimentation and concept of operations development for reusable space vehicle technologies.”  What does that mean, exactly?  Well, for one thing, it’s likely still being used a proof of concept for reusable space-faring gear, but based on the secrecy surrounding it, that’s probably not all.  Evidence suggests the X-37B may be used for espionage, as it often follows an orbit that takes it above American opponents like Russia and China and because of its regular returns to the earth’s surface, it can be fitted with all sorts of different and experimental eavesdropping equipment.

“The hard work of the X-37B OTV team and the 45th Space Wing successfully demonstrated the flexibility and resolve necessary to continue the nation’s advancement in space,” said Randy Walden, the director of the Air Force Rapid Capabilities Office. “The ability to land, refurbish, and launch from the same location further enhances the OTV’s ability to rapidly integrate and qualify new space technologies.”