A massive Chinese rocket ferrying space station modules into orbit came home to planet Earth, but its precise whereabouts were something of a mystery. On Monday, China launched a Long March-5B rocket loaded with the final section of Beijing’s Tiangong space station, which is now complete. The rocket’s booster then spent the past week drifting back to Earth, but its 20,500 mph velocity made it difficult to forecast where it would reenter the atmosphere. U.S. Space Command tweeted Friday morning to say the rocket had reentered at 4:01 a.m. MT over the Pacific Ocean. “For details on the uncontrolled reentry’s impact location, we once again refer you to [China].” A previous prediction made by the non-profit Aerospace Corporation put the possible landing area as being so big that 88 percent of the world’s population live in it. More