Huge Chinese Rocket Stage Falls to Earth in Uncontrolled Reentry
China celebrated success last week when its prototype crewed spacecraft returned to Earth after several days in orbit. It got there with the aid of a new, more powerful rocket called the Long March 5B. The core stage remained in space until yesterday when it splashed down in the Atlantic Ocean. This was no piddly little chunk of space debris, though. The Chinese rocket stage was the largest uncontrolled reentry in decades.
The Long March 5B is China’s next-generation launch platform with a payload capacity slightly higher than the SpaceX Falcon 9. China hopes to use the new rocket to assemble a modular space station in orbit of Earth, so it weighed down the test capsule with extra fuel to simulate 20-ton station segments. The spacecraft returned to Earth safely last week, but the core stage rocket remained in space until yesterday when it plummeted uncontrolled to Earth.
Most space launches include the release of rocket stages over open ocean, or in the case of SpaceX, landed on a drone ship. Uncontrolled reentry of space debris is not uncommon, but the pieces are rarely as large as the 17.8-ton Long March stage. This was the largest uncontrolled reentry since the 39-ton Soviet Salyut 7 space station crashed to Earth in 1991.
At 11:21 Eastern time the CZ-5B rocket is predicted to pass 170 km directly above Central Park, New York. I’ve never seen a major reentry pass directly over so many major conurbations!
— Jonathan McDowell (@planet4589) May 11, 2020
The odds of an unneeded satellite or rocket segment hitting anything important are small, but space agencies still try to drop them in the ocean via controlled reentry. China did plan for the booster to fall to Earth, but it didn’t know where. Its resting place turned out to be just off the coast of Africa, about 100 miles from Mauritania.
Astronomer Jonathan McDowell from the Harvard-Smithsonian Center for Astrophysics says he’s never seen a major reentry pass over as many populated areas as the Long March 5B did. It even flew just 105 miles (170 kilometers) over New York City during its descent. Being an uncontrolled reentry, the Chinese government didn’t have any say over the course the stage took, but you could argue it was irresponsible to allow it to reenter the atmosphere without any plan.
China is moving aggressively to send astronauts beyond low-Earth orbit, and the recovery of its experimental capsule from a high orbit is a significant step in accomplishing that goal. We can expect more rocket segments to drop out of the sky as China continues its testing. Hopefully, they’re a bit more careful where the equipment drops, though.