facebooktwittertelegramwhatsapp
copy short urlprintemail
+ A
A -
webmaster
dpa
Beijing
Chinese state media has dismissed concerns about falling debris from a rocket launched as part of the country’s efforts to build its own space station.
The debris is “very likely to fall in international waters and people needn’t worry,” said an expert cited by Global Times, a newspaper often used as an English-language state mouthpiece.
Space experts had warned of possible debris from an uncontrolled re-entry of the 20-tonne main section of the launch vehicle into Earth’s atmosphere, which they estimate will come at the weekend or on Monday.
The European Space Agency (ESA) said on Thursday it expects the launch vehicle section to re-enter the Earth’s atmosphere on Sunday at 0731 GMT - but plus or minus about 18 hours. The ESA stressed that all forecasts have considerable uncertainties.
The agency added that the area in question includes any part of the Earth’s surface between the latitudes of 41.5 degrees north and 41.5 degrees south.
In Europe, this includes parts of Spain, Italy, Portugal, Malta and Greece. In general, large parts of North and South America, South Asia, Africa and Australia belong to the risk area.
The Long March 5B craft took the Tianhe (Heavenly Harmony) core module to space last Thursday, marking the start of construction of China’s space station.
It is “common in the aerospace field” for debris to fall back to Earth, the Global Times wrote. The paper characterised the warnings as “nothing but Western hype of the ‘China threat’ in space technology advancement.”
Citing expert Wang Ya’nan, the editor in chief of Aerospace Knowledge magazine, the outlet reported that China’s space authorities carefully considered the development of falling debris during the design of the rocket and the choice of a launch site.
“Most of the debris will burn up during re-entry into the Earth’s atmosphere, leaving only a very small portion that may fall to the ground, which will potentially land on areas away from human activities or in the ocean,” Wang Ya’nan said.
Experts also explained that the launch vehicle was made mainly from lightweight materials, most of which will easily burn up during re-entry, according to Global Times.
The ESA’s Office of Space Residues had said it was currently virtually impossible to predict which parts would survive re-entry.
Materials with high melting temperatures, such as engine structures, posed a particular risk. In general, however, most objects would burn up completely during re-entry, the experts said.
Since much of the Earth is covered with water and large parts are uninhabited, the risk to individuals is much lower than for everyday risks such as driving a car, they said.
Astrophysicist Jonathan McDowell of the Harvard & Smithsonian Center for Astrophysics in Cambridge in the United States told dpa earlier in the week it would be “at worst like a small plane crash but stretched out in a line over hundreds of kilometres,” he told dpa. It was uncertain how many fragments would remain after re-entry, he said, “But enough to cause damage.”
“The more likely possibility is the core stage will fall in an uninhabited place like Earth’s oceans, which cover 70 percent of the planet,” expert Andrew Jones also wrote on spacenews.com.
“The odds of a particular individual being hit by space debris are exceedingly low, once estimated at 1 in several trillion.”
Debris had fallen in the West African nation of Ivory Coast just six days after the first flight of the Long March 5B in May 2020, damaging several homes in villages.
McDowell criticised China’s new rocket for not meeting today’s standards. Other countries have made sure that the bulk of their missiles did not stay in orbit, but were put on a trajectory to crash specifically into the sea.
“With the Long March 5B ... China did not take either of these approaches, it designed the core stage to just stay in orbit and re-enter at some random place a week later thanks to atmospheric drag,” he said.
“This design approach is negligent by comparison with the current standards of other countries.”
copy short url   Copy
07/05/2021
350