CHINA has revealed it is closely following an uncontrollable rocket that will blast back through the atmosphere next weekend.
Remains of the huge rocket will return to Earth in an uncontrolled reentry but pose little risk to anyone on the ground, the Beijing government said on Wednesday.
The Long March 5B rocket launched on Sunday to deliver a lab module to the new Chinese space station being built in orbit.
It was the third flight of China’s most powerful rocket since its first launch in 2020.
As happened during the first two flights, the entire main core stage of the rocket – which is 30 meters long and weighs 22 tons – has already entered low Earth orbit.
According to US experts, it is expected to tumble back to Earth once atmospheric friction drags it down.
Eventually, the rocket body will disintegrate as it plunges through the atmosphere.
However, it is large enough that numerous chunks are likely to survive a fiery return to rain debris over an area about 2,000 km (1,240 miles) long and about 70 km (44 miles) wide, independent US-based analysts said Wednesday.
The probable location of the debris field cannot be determined in advance.
Experts will be able to narrow the potential impact zone closer to reentry in the coming days.
According to the Aerospace Corp., a government-funded non-profit research center near Los Angeles, the return of the latest available tracking data projects will take place on Sunday around 1:24 a.m. UK time, plus or minus 4 p.m.
The overall risk to people and property on the ground is quite low, aerospace analyst Ted Muelhaupt told reporters in a news conference.
That’s because 75 percent of the Earth’s surface in the potential path of debris is water, desert or jungle.
However, there is a possibility that pieces of the rocket will come down over a populated area.
That famously happened in May 2020 when fragments of another Chinese Long March 5B landed on Ivory Coast, damaging several buildings. No injuries were reported, Muelhaupt said.
By contrast, he said, the United States and most other space-faring nations generally go to the extra cost of designing their rockets to avoid large, uncontrolled reentry.
That need has been largely perceived since large portions of NASA’s Skylab space station fell out of orbit in 1979 and landed in Australia.
In general, the odds of someone being injured or killed by falling rocket debris this weekend range from one in 1,000 to one in 230.
That’s well above the internationally accepted risk threshold of one in 10,000, he told reporters.
But the risk to a single individual is much lower, on the order of six chances per 10 trillion. By comparison, he said, the odds of being struck by lightning are about 80,000 times greater.
China’s Foreign Ministry spokesman Zhao Lijian said the debris is very unlikely to harm aviation or people and property on the ground. He said most of the missile’s components would be destroyed upon return.
Last year, NASA and others accused China of being opaque after the Beijing government kept silent about the estimated trajectory of debris or the return window of its final Long March rocket flight in May 2021.
Debris from that flight landed harmlessly in the Indian Ocean.
A few hours after Zhao spoke on Wednesday, the China Manned Space Agency (CMSA) released the estimated position of its latest rocket in a rare public statement.
At 4 p.m. (0800 GMT), the agency said the rocket orbited Earth in an elliptical orbit that was 263.2 km high at its farthest point and 176.6 km high at its nearest point.
The CMSA did not provide estimated re-entry details on Wednesday.
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