The U.S. Space Force’s X-37B just completed its eighth mission after spending over 900 days in orbit with a shuttered payload bay doing classified work nobody outside the Pentagon fully understands. China operates an eerily similar spacecraft called the Shenlong — and both vehicles may be capable of something far more consequential than experiments. The X-37B Looks Like a Mini Space Shuttle. Its Missions Are Fully Classified. 19FortyFive staff h…