The Air Force’s secretive space plane returns after more than two years

• 

  The Air Force's X-37B Orbital Test Vehicle Mission 5 successfully landed Sunday morning at NASA's Kennedy Space Center Shuttle Landing Facility [credit: U.S. Air Force ]

Early on Sunday, the US Air Force announced that its X-37B space plane had returned to Earth, touching down at Kennedy Space Center's Shuttle Landing Facility in Florida. The uncrewed space plane had spent 779 days, 17 hours in space, breaking its own long-duration record.

During four previous missions dating back to 2010, the X-37B had previously flown for as long as 717 days, 20 hours-during a period from May, 2015 through May, 2017. The latest mission launched on September 7, 2017 aboard a Falcon 9 rocket.

As ever, the biggest question surrounding the Air Force's space plane concerned what it was up to during its long flight in low-Earth orbit. "The spaceplane conducted on-orbit experiments," an Air Force news release stated, blandly. "The distinctive ability to test new systems in space and return them to Earth is unique to the X-37B program and enables the US to more efficiently and effectively develop space capabilities necessary to maintain superiority in the space domain."

Read 4 remaining paragraphs | Comments