Chinese Long March 5B Rocket Stage – Space & Astronomy in an uncontrolled fall

The stage of the Chinese Long March 5B missile that on April 29 brought the first unit of the Tiangong Space Station into orbit in an uncontrolled fall towards the Earth. The news, reported by various international websites, was confirmed by Luciano Anselmo, from the Institute of Information Science and Technology of the National Research Council (Isti-Cnr) in Pisa, to the news.

This is the second time this has happened with this version of the missile. The first – Anselmo notes – was in 2020, when shrapnel hit some villages in West Africa, ” but then the news passed almost unnoticed due to the Covid-19 pandemic emergency.

This version of the Long March missile was first launched in May 2020, when it took the Chinese astronaut’s shuttle into orbit on an unmanned test flight. Until then, the main stage of the missile, which weighed 20 tons, fell to the ground uncontrollably.

The launch on April 29 was flawless, but the truth is, Anselmo notes, “after launch, the rocket stage was abandoned in orbit and no longer showed signs of life.” In other words, it acts like a “negative car” and the only effect it is exposed to is “atmospheric brake, which causes it to retract towards the ground.”

The suspicion is also confirmed by the orbit it describes, similar to the one traveled in 2020 by its predecessor, and also in 2018 by the prototype of an ancient Chinese space station. Currently – he notes – the fall can occur in a range between 41.5 degrees in the north and 41.5 degrees in the south, which also includes central and southern Italy. ”However, it is too early to draw any conclusions because its orbit can be subject to differences.” Yield – as The expert says – it is likely to be in the middle of next week, with uncertainty for a few days.

In the base version of Long March 5, the main stage does not reach orbit and sinks into the ocean immediately after carrying its payload to the required altitude, but the 5B version is used to place very massive loads in a very low orbit, as was the first core of the Chinese space station, ”notes Anselmo Basically, all the propellants of the rocket are exploited to bring an exceptional payload to its destination, after which it is no longer possible to control its re-entry.

“A year ago, the missile stadium fell on West Africa and shrapnel fell on some villages,” he added. If the pandemic emergency had cast a shadow over what had happened, “that story opened the eyes of the space community; the question arose as to why not attempting to move the rocket stage to another orbit. And there was someone safe – says Anselmo – that after that time it would likely try. China controlled return. “