A risk ” low “ or “Tiny”, but not zero: a Chinese rocket must make its uncontrolled return to the Earth’s atmosphere this weekend, China and many experts, however, deeming the hypothesis of damage on Earth to be minimal.
The Asian country placed the first module of its space station in orbit on April 29, thanks to a Long-March 5B carrier rocket – the most powerful and imposing Chinese launcher. It is the first stage of this rocket, currently in orbit, which must return to Earth. It is gradually losing altitude and the point of impact of its fall remains difficult to predict for the moment.
According to the latest estimates from the US Department of Defense, re-entry into the atmosphere should occur around 11 p.m. (GMT) on Saturday (1 hour Sunday in Paris). But this forecast has a significant margin of error of nine hours on either side of this schedule. The window should gradually narrow as the rocket gets closer.
After a long embarrassed silence from the Chinese space and diplomatic authorities, Beijing finally reacted on Friday. “The majority of the components [de la fusée] will be burned and destroyed upon re-entry into the atmosphere “, assured Wang Wenbin, a spokesperson for the Chinese foreign ministry. “The probability of causing damage to air activities or (to people, buildings and activities) on the ground is extremely low”, he assured during a press conference.
Chinese media remain discreet
Chinese media provided minimal coverage of the event on Saturday, contenting themselves with repeating the words of the diplomacy spokesperson. If parts of the rocket remain intact after re-entering the atmosphere, there is a good chance that they will be damaged at sea, since the oceans occupy 70% of the earth’s surface. But they could also crash into an inhabited area or into a ship.
“We hope they land in a place where they won’t harm anyone”said Mike Howard, a spokesman for the US Department of Defense, on Friday, recalling that the United States was tracking the path of the rocket. US Defense Minister Lloyd Austin assured this week that his country had no intention of destroying the rocket. He hinted, however, that its launch was not planned with enough care by China.
The risk of debris from the heavy launcher touching an inhabited area exists, but is however low, according to several experts interviewed by Agence France-Presse. “Considering the size of the object, there are necessarily large pieces that will remain”, anticipates Florent Delefie, astronomer at the Paris-PSL Observatory. But the probability of an impact on an inhabited area is “Tiny, less than one in a million, probably”, reassures Nicolas Bobrinsky, head of the engineering and innovation department of the European Space Agency (ESA).
“It is not a good practice”
“No need to worry too much”, also notes Jonathan McDowell, astronomer from the Harvard-Smithsonian Center for Astrophysics, in the United States, and great specialist in space debris. “But the fact that a ton of metal shards hit the Earth at hundreds of kilometers per hour is not a good practice, and China should review the design of the Long March 5B missions to avoid this. . “
In 2020, debris from another Longue-Marche 5B rocket crashed into villages in Côte d’Ivoire, causing damage, but no injuries. In April 2018, China’s Tiangong-1 space station disintegrated when it entered the atmosphere, two years after it ceased to function.
China has been investing billions of euros in its space program for several decades. The Asian country sent its first astronaut into space in 2003. In early 2019, he landed a craft on the far side of the moon – a world first. Last year, he brought back samples of the Moon and finalized Beidou, his satellite navigation system (competitor of the American GPS). China plans to land a robot on Mars in the coming weeks. She also announced that she wanted to build a lunar base with Russia.