The Air Force X-37B orbital test vehicle set a new milestone on Monday.
The spacecraft, modeled after NASA's X-37 program, has 717 days, 20 hours and spent 42 minutes in space On the morning of the 26th of August – the last record set by the previous mission of the X-37B.
The unmanned spacecraft is wrapped in secrecy and its missions are classified so little is known about its work. According to the Air Force, the spacecraft "experiments and tests in space technology of long duration to perform."
Technologies tested in the program include navigation and control, thermal protection systems, avionics, lightweight electromechanical flight systems, advanced materials and, among other things, autonomous orbital flight.
Despite limited information, Former Air Force Secretary Heather Wilson said at the Aspen Security Forum in July that the orbit of the vehicle makes it difficult for opponents to see where the spacecraft will appear next. Wilson suggested that the unmanned spacecraft could change its orbit ̵
"We know they're going crazy," Wilson said. "And I'm really happy about that."
Wilson's comments came shortly after the launch of NASA's X-37 program on Twitter, which released the Dutch astronomer Ralf Vandenbergh on July 3. The program was transferred to the Defense Advanced Research Project Agency five years later, and the Air Force has since successfully completed four X-37B missions totaling 2,085 days in orbit.
The last OTV mission designated as OTV-5, launched on September 7, 2017 from the Cape Canaveral Air Force Station in Florida.