In a rare disclosure, the Pentagon provides an update on the X-37B spaceplane

The US military's X-37B spaceplane will use aerobraking to lower its orbit after 9 months in a high, elliptical orbit. This first-time maneuver for the X-37B will use Earth's atmosphere to reduce speed and altitude while saving fuel, allowing safe disposal of its service module. The technique demonstrates new capabilities for maneuvering in space without propellant. The current mission has been testing radiation effects and space domain awareness technologies.