SpaceX's powerful falcon heavy rocket lofts secretive US military spaceplane into orbit

SpaceX’s powerful Falcon Heavy rocket lofted a secretive space plane for the US Space Force on Thursday evening from Florida, the first time the rocket was used to send the Boeing Co.-built experimental spacecraft to orbit.

A SpaceX Falcon Heavy rocket carrying the X-37B spaceplane for the U.S. Space Force lifts off from Kennedy Space Center in Florida, Thursday, Dec. 28, 2023. (AP)

SpaceX's powerful Falcon Heavy rocket lofted a secretive space plane for the US Space Force on Thursday evening from Florida, the first time the rocket was used to send the Boeing Co.-built experimental spacecraft to orbit.

The launch, which lifted off at 8:07 p.m. local time, marked the start of the seventh mission for the Space Force's secretive spaceplane, the X-37B. Shaped like a mini-space shuttle, the X-37B is an uncrewed and reusable experimental test platform that the Defense Department deploys in orbit, sometimes for years at a time.

Prior to launch, which took place Thursday after several earlier delays, the X-37B's most recent mission launched in May 2020, spending a record-setting 908 days in orbit. The vehicle's mission came to an end in November 2022, with the X-37B returning from space and gliding to a runway at NASA's Kennedy Space Center Shuttle Landing Facility.

What the X-37B actually does while in orbit is not fully clear. During the vehicle's last mission, a number of experiments were performed on the spacecraft, including research for NASA that examined how seeds react to being in space for long periods of time, and how certain materials fared when exposed to space.

The US Space Force has released limited details about what the X-37B's current mission will entail. It “will expand the USSF's knowledge of the space environment for future space domain awareness technologies,” the Space Force said in a statement.

The latest mission was the second time that the X-37B has flown on a SpaceX vehicle. The spacecraft also launched on top of a Falcon 9 in 2017.