Plunging back to earth: Chinese rocket set for re-entry | Space News

According to data from tracking centers in Europe and the US, the remains of China’s largest missile, which was fired last week, is expected to crash through the atmosphere again in the coming hours.

The main 18-ton segment of the Long March 5B rocket, which launched the first module of the new Chinese space station into orbit on April 29, is now in free fall. Experts have said it is difficult to say exactly where and when it will re-enter the atmosphere.

China’s Foreign Ministry said Friday that most of the debris would burn on re-entry and most likely would not cause any damage.

“The likelihood of causing damage … on the ground is extremely slim,” Chinese Foreign Ministry spokesman Wang Wenbin told reporters.

The U.S. Space Command estimates re-entry will be at 2:11 a.m. GMT plus or minus an hour on Sunday, while the Center for Orbital Reentry and Debris Studies (CORDS) at Aerospace Corporation, a federally funded space-oriented research and Development Center, updated its forecast to two hours on either side of 03:02 GMT when the missile re-entered the Pacific.

The EU Space Surveillance and Tracking (EU SST) announced that its most recent forecast for the time of the re-entry of the Long March 5B missile body was 139 minutes on either side of 02:32 GMT on Sunday.

EU SST said the statistical probability of a ground impact in a populated area was “low” but noted that the uncontrolled nature of the object made predictions uncertain.

Space-Track reported on data collected by the US Space Command and estimated that the debris would come back over the Mediterranean basin.

Visitors walk through a model of China’s Tianhe space station at an exhibition about the development of Chinese space exploration last month [Tingshu Wang/Reuters]At a speed of approximately 13.7 km / s per second, a difference of only one minute in the time of reentry means a difference of hundreds of miles on the ground.

“This is difficult to predict and not an accurate measurement,” wrote Space-Track on Twitter.

The Long March 5B – consisting of a core stage and four boosters – started on April 29 with the unmanned Tianhe module from the Chinese island of Hainan, which contains the future living quarters of a permanent Chinese space station.

The missile will be followed by 10 more missions to complete the station.

Most experts believe the risk to humans is small.

“Given the size of the object, large pieces inevitably remain,” said Florent Delefie, astronomer at the Paris PSL Observatory.

“The likelihood of debris ending up in an inhabited area is slim, probably one in a million.”

In May 2020, parts of the first long March 5B fell in Ivory Coast and damaged several buildings. No injuries were reported.

Debris from Chinese rocket launches is not uncommon in China. In late April, authorities in Shiyan city, Hubei province, issued a notice to people in the surrounding county to prepare for evacuation as parts were expected to land in the area.

“Long March 5B’s re-entry is unusual as the rocket’s first stage reached orbital velocity during launch rather than falling within range as usual,” Aerospace Corporation said in a blog post.

“The empty missile body is now in an elliptical orbit around the earth, where it is being pulled in the direction of an uncontrolled re-entry.”

The empty core stage has been losing altitude since last week, but the rate of its decay in orbit remains uncertain due to unpredictable atmospheric variables.

It is one of the largest pieces of space debris returning to Earth. Experts estimate its dry matter at around 18 to 22 tons.

The core phase of the first Long March 5B, which returned to Earth last year, weighed nearly 20 tons and was only surpassed by wreckage from the Columbia Space Shuttle in 2003, the Soviet Union’s Salyut 7 space station in 1991, and NASA’s Skylab in 1979.