Our space debris expert is back with answers about the giant rocket stage left behind after the Oct. 31 Long March 5B Launch. — On April 29, 2021, China launched the first module, Tianhe, of its Tiangong space station on their heaviest rocket to date, the Long March 5B. The rocket body traveled with the module to orbit, resulting in an uncontrolled reentry of the rocket’s core stage. …