The latest launch marked the fifth launch and landing of these Falcon Heavy two-side boosters, the company added.
"On Thursday, December 28 at 8:07 p.m. ET [01:07 GMT on Friday], Falcon Heavy launched the USSF-52 mission to orbit from Launch Complex 39A (LC-39A) at Kennedy Space Center in Florida," SpaceX said in a statement on the website.
The United States Space Force (USSF) said in late November that the US Department of the Air Force Rapid Capabilities Office, in partnership with USSF and SpaceX, was making final preparations to launch the seventh mission of the unmanned X-37B Orbital Test Vehicle, one of the most secretive projects of the US military, with "a wide range of test and experimentation objectives," including "operating in new orbital regimes, experimenting with space domain awareness technologies and investigating the radiation effects to NASA materials."
US broadcaster reported on Thursday, following the launch, that it was unclear where exactly the "mysterious spacecraft" that would carry out cutting-edge research was going or how long it would stay in space.
Russia, China Against Arms Race in Space
Earlier Sputnik reported that Pentagon is planning to deploy a new constellation of spy satellites, with purpose to observe Russian and Chinese space projects.
Moscow repeatedly slammed the very idea of militarization of space. In 2008, Russia and China introduced Proposed Prevention of an Arms Race in Outer Space (PAROS) Treaty, yet Washington ignored this initiative. In 2017, Pentagon specialists referred to space as to another “war-fighting domain”. In 2019, Washington established Space Force as separate entity in US army.