The U.S. military’s secretive X-37B spaceplane is scheduled for launch on Dece. 28, was announced by SpaceX.

This launch marks the seventh mission of the X-37B, a robotic spaceplane, which will be carried atop a SpaceX Falcon Heavy rocket from NASA’s Kennedy Space Center in Florida. The X-37B is set to enter a higher orbit than in previous missions, showcasing advancements in its capabilities and the launch vehicle’s power.

SpaceX has been preparing for this launch amidst previous delays and false starts, emphasizing the mission’s complexity and importance. The X-37B, known for its elusive nature and advanced technology, plays a crucial role in the U.S. Space Force’s operations.