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Beijing (AP) - China has denied a danger from falling remains of its rocket used to build the Chinese space station.
It is "very unlikely" that they could cause damage, said Foreign Ministry spokesman Wang Wenbin on Friday in response to journalists' questions in Beijing.
The rocket stage will burn up and destroy when it re-enters the earth's atmosphere.
"This is international practice."
Experts expect an “uncontrolled” re-entry at the weekend.
The rocket was not built to be driven by engines in such a way that it enters the atmosphere over an uninhabited area or the sea.
A warning was given of a possible rain of debris that could be enough to cause damage.
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Germany is probably not in the risk zone that covers every part of the earth's surface between the 41.5.
Degrees north and 41.5.
Degrees south latitude.
In Europe, for example, parts of Spain, Italy, Greece and Portugal are included.
It also includes regions of North and South America and South Asia as well as all of Africa and mainland Australia.
The European Space Agency's space debris office, Esa, expects the debris to re-enter the earth's atmosphere between Saturday evening and early Sunday afternoon.
The new, particularly stable rocket of the “Long March 5B” type launched the “Tianhe” (Heavenly Harmony) core module into space last Thursday.
The young space nation began building its own space station.
At 21 tons, the rocket stage and its predecessor on its maiden flight in May 2020 are the sixth and seventh largest objects that have ever re-entered the earth's atmosphere, reported Marlon Sorge from the Aerospace Corporation's Center for Reentry Studies (CORDS) in California.
He named the space laboratory Skylab, the Russian space stations Mir and Salyut 6 and 7 as well as the Saturn V rocket stage that Skylab brought into space.
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“As a general rule, 20 to 40 percent of the mass of a large object reaches the ground. The exact extent depends on the design. Normally, the rocket stages are not built to go into orbit, said the expert. Rather, their trajectory is planned in such a way that they fall into a safe area such as the ocean after take-off. When a missile is in orbit, a deorbit maneuver must be undertaken, in which thrusters are used to select the re-entry point in a controlled manner.
"The ability to perform a deorbit maneuver depends on the design and mission of the missile," said Sorge. It is not uncommon for a controlled reentry to be planned in advance, as heavy rocket stages pose a greater risk to people on Earth. "This is the preferred approach according to international standards and is quickly becoming a global norm."
The astrophysicist Jonathan McDowell from the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, had criticized the rocket's design as "negligent".
It does not meet today's standards.
“In the worst case”, it would be like the crash of a small plane spread over hundreds of kilometers.
After the first flight of the new type of missile in May 2020, debris fell in the West African Ivory Coast and, according to local reports, had damaged houses.
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© dpa-infocom, dpa: 210507-99-508390 / 2
Aerospace Interview Marlon Sorge
Aerospace trajectory and forecast