The remnants of China’s largest rocket have plummeted back to Earth, plunging into the Indian ocean near the Maldives, according to Chinese state media, ending days of speculation over where the debris would hit.
Most of the debris burned up in the atmosphere, it reported, citing the Chinese Manned Space Engineering office.
Parts of the 30-metre core of the Long March 5B rocket re-entered the atmosphere at 10.24am Beijing time (2.24am GMT) and landed at a location with the coordinates of longitude 72.47 degrees east and latitude 2.65 degrees north, state media cited the office as saying.
Nasa was critical of China’s lack of transparency over the rocket’s re-entry, saying spacefaring nations had a duty to minimise the risks to people and property on Earth.
“It is clear that China is failing to meet responsible standards regarding their space debris,” said Nasa administrator Bill Nelson, a former senator and astronaut who was picked for the role in March.
“It is critical that China and all spacefaring nations and commercial entities act responsibly and transparently in space to ensure the safety, stability, security, and long-term sustainability of outer space activities.”
The US Space command confirmed the re-entry into the atmosphere of the rocket over the Arabian peninsula, but said it was unknown if the debris had hit land or water. “The exact location of the impact and the span of debris, both of which are unknown at this time, will not be released by US Space Command,” it said in a statement.
Space watchers around the world have been anticipating the arrival of the Long March 5B space rocket since it started to lose altitude last week amid concerns it was out of control. It is one of the largest pieces of space debris to return to Earth and prompted the White House to call for “responsible space behaviours”. China’s failure to issue strong safety reassurances in the run-up to the re-entry fuelled anxiety.
During the rocket’s flight, Harvard-based astrophysicist Jonathan McDowell told Reuters that the potential debris zone could have been as far north as New York, Madrid or Beijing, and as far south as southern Chile and Wellington, New Zealand.
“It makes the Chinese rocket designers look lazy that they didn’t address this,” said McDowell, a member of the Harvard-Smithsonian Center for Astrophysics.
The Global Times, a Chinese tabloid published by the official People’s Daily, dismissed as “western hype” concerns that the rocket was “out of control” and could cause damage.
“It is common practice across the world for upper stages of rockets to burn up while reentering the atmosphere,” said Wang Wenbin, a spokesman at the Chinese foreign ministry, at a regular media briefing on Friday.
“To my knowledge, the upper stage of this rocket has been deactivated, which means that most of its parts will burn up upon re-entry, making the likelihood of damage to aviation or ground facilities and activities extremely low,” Wang said at the time.
The Long March 5B – comprising one core stage and four boosters – lifted off from China’s Hainan island on 29 April with the unmanned Tianhe module, which contains what will become living quarters on a permanent Chinese space station. The rocket is set to be followed by 10 more missions to complete the station.
The empty core stage has been losing altitude since last week, and experts estimated its dry mass to be around 18 to 22 tonnes.
Long March 5 rockets have been integral to China’s near-term space ambitions – from the delivery of modules and crew of its planned space station to launches of exploratory probes to the moon and even Mars. The Long March launched last week was the second deployment of the 5B variant since its maiden flight in May last year.
In May 2020, pieces from the first Long March 5B fell on Ivory Coast, damaging several buildings. No injuries were reported.
Debris from Chinese rocket launches is not uncommon within China. In late April, authorities in the city of Shiyan, Hubei Province, issued a notice to people in the surrounding county to prepare for evacuation as parts were expected to land in the area.
“The Long March 5B re-entry is unusual because during launch, the first stage of the rocket reached orbital velocity instead of falling down range as is common practice,” the Aerospace Corporation said in a blog post.
The core stage of the first Long March 5B that returned to Earth last year weighed nearly 20 tonnes, surpassed by debris from the Columbia space shuttle in 2003, the Soviet Union’s Salyut 7 space station in 1991, and Nasa’s Skylab in 1979.
https://www.theguardian.com/science/2021/may/09/chinese-rocket-debris-earth-indian-ocean
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