The US Air Force's secret space plane has just landed back on Earth after a record-breaking mission.
After spending two years in orbit, the mystery X-37B landed at Nasa's Kennedy Space Centre in Florida early Sunday.
The Air Force has been keeping quiet about what the plane did in space after launching aboard a SpaceX rocket in 2017.
Its 780-day mission sets a new endurance record for the reusable test vehicle.
The aircraft looks like a space shuttle but is one-fourth the size at 29 feet.
Officials said this latest mission successfully completed its objectives.
Experiments from the Air Force Research Laboratory were aboard.
This was the fifth spaceflight by a vehicle of this kind.
The sixth is planned next year with another launch from Cape Canaveral.
According to Air Force Secretary Barbara Barrett, "Each successive mission advances our nation's space capabilities."
