The mysterious US Air Force reusable space plane has landed back on Earth after being in orbit for 780 days.
The top secret mission launched on 7 September 2017, and the exact purpose of the mission was never properly explained.
Upon it’s return, the Air Force said in a statement that the ability to test new systems in space and return to Earth is “unique to the X-37B program and enables the U.S. to more efficiently and effectively develop space capabilities necessary to maintain superiority in the space domain.”
According to Science Alert, previous announcements about the tests have said they are for navigation and control, thermal protection systems, avionics, advanced propulsion systems, reentry and landing.
This is the fifth long-duration mission by these kind of aircraft, who have a total of 2,865 days spent in orbit.
“The safe return of this spacecraft, after breaking its own endurance record, is the result of the innovative partnership between government and industry,” said Air Force Chief of Staff Gen. David L. Goldfein. “The sky is no longer the limit for the Air Force and, if Congress approves, the U.S. Space Force.”
The statement also mentioned that the plane gave a lift to some small satellites. These were not registered with the Register of Objects Launched into Outer Space, which has been in effect since 1962 by the United Nations, and so also brings up questions about the US ignoring this convention.
The Air Force are preparing to launch the sixth X-37B mission from CCAFS in 2020.
Image: US Air Force