There are concerns China's latest rocket launch could see out-of-control debris come hurtling back towards inhabited parts of Earth.
China launched an unmanned module on Thursday (local time) containing what will become living quarters for three crew on a permanent space station it plans to complete by the end of 2022, state media reported.
The module, named "Tianhe", or "Harmony of the Heavens", was launched on the Long March 5B, China's largest carrier rocket.
The core of the Long March 5B then entered a temporary orbit before what experts say will be one of the largest ever uncontrolled re-entires, with some fearing rocket parts could crash down on inhabited parts of the globe.
"It’s potentially not good," Jonathan McDowell, an astrophysicist at the Astrophysics Centre at Harvard University, told The Guardian.
"Last time they launched a Long March 5B rocket they ended up with big, long rods of metal flying through the sky and damaging several buildings in the Ivory Coast," he said.
In that incident in May last year, local reports claimed a piece of 12-metre-long debris fell from the sky, crashing in the village of Mahounou.
Fortunately, no one was reported to be injured.
A similar incident happened in southern China in 2018 with locals posting videos of the falling rocket parts.
Mr McDowell said pieces from the latest launch that survive re-entry could prove to be the "equivalent of a small plane crash" scattered over about 160 kilometres.
According to Space News, US military radars have tracked the rocket travelling at about seven kilometres per second in orbit, but when it will fall to Earth is hard to know.
China strives to become space power
Tianhe is one of three main components of what would be China's first self-developed space station, rivalling the only other station in service — the International Space Station (ISS).
In the later missions, China will launch the two other core modules, four manned spacecraft and four cargo spacecraft.
But China has repeatedly come under fire for its ostensibly lax approach to space debris.
Work on the Chinese space station program began a decade ago with the launch of a space lab Tiangong-1 in 2011, and later, Tiangong-2 in 2016.
Both helped China test the program's space rendezvous and docking capabilities.
China aims to become a major space power by 2030. It has ramped up its space program with visits to the moon, the launch of an unmanned probe to Mars and the construction of its own space station.
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