X-37B Spaceplane's Historic Mission Aboard Falcon Heavy.

The US Space Force's secretive X-37B spaceplane is set for its seventh mission, known as OTV-7.

OTV-7 marks a historic launch as it will be transported into orbit by SpaceX's Falcon Heavy rocket for the first time.

The launch is scheduled for December 7 from Cape Canaveral, Florida.

The X-37B, having completed six missions on a ULA Atlas V rocket, will now bear USSF livery, reflecting program management transfer to the US Space Force.

The mission aims to experiment with new space technologies, including testing the reusable vehicle in new orbital regimes and studying radiation effects on plant seeds.

General B. Chance Saltzman describes the upcoming experiments as "ground-breaking" and essential for enhancing safe operations in space.

The Falcon Heavy, with 27 Merlin engines, will carry the X-37B into orbit, marking a significant milestone in space exploration. The USSF did not disclose the planned duration of OTV-7.