Debris from a recently launched large Chinese rocket returned to Earth in an uncontrolled re-entry over the Indian Ocean on Saturday afternoon.
The US Space Command confirmed the re-entry of the debris at approximately 12:45 pm ET, referring all questions about the precise location of the re-entry and the dispersal of the debris to the Chinese government.
In the final hours before the rocket booster fell from orbit, a populated area of Mexico’s Baja California peninsula near Cabo San Lucas had been in the potential path of the debris, according to an assessment by the Aerospace Corporation.
Because the booster stage raced around Earth’s orbit every 90 minutes, the exact point at which it would drop from the sky had been impossible to predict.
The falling space junk is the 23-ton booster stage of China’s most powerful Long March 5B-Y3 rocket, which launched on July 24 to deliver the Wentian Module to the Tiangong Space Station in the china
The latest ground track from the Aerospace Corporation shows the trajectory of the falling booster rocket during the reentry window from 2:15 p.m. to 2:15 p.m. ET on Saturday. The icon shows the midpoint of the window. The red line shows the ground track before the middle of the window, and the yellow line shows the ground track after the center
The falling space junk is the 23-ton booster stage of China’s most powerful Long March 5B-Y3 rocket, which launched on July 24 (above) to deliver the Wentian Module to the station China’s Tiangong space station.
The Aerospace Corporation had said that “there is a non-zero probability” of the debris landing in a populated area, meaning it’s not impossible, so it could happen.
“A re-entry of this size will not burn up in the Earth’s atmosphere,” El Segundo, California-based Aerospace Corporation said.
“The general rule is that 20-40 percent of the mass of a large object will reach the ground, although it depends on the design of the object.”
But according to Aerospace Corporation consultant Ted Muelhaupt, the overall risk to people and property on the ground is quite low, since the vast majority of Earth’s surface in the potential re-entry zone is water, desert or jungle.
Speaking during a live-streamed briefing on Twitter Thursday, Muelhaupt also said there is a “99.5 percent chance nothing will happen.”
“Personally, if that occurred to me, I would run out with a camera to see it, because I think it would be more visual. [opportunity] than a real risk,” he said.
Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics, added: “The worst case of this event will be less severe than a single cruise missile attack that we have been seeing every day in the Ukraine war, so come on put it in some perspective here.
The Rebel booster delivered the Wentian module to China’s Tiangong space station (seen in an earlier rendering)
An engineer sits in front of a monitor showing an animation of space debris at the European Space Agency’s (ESA) new Space Safety Centre, located at the European Satellite Operations Center (ESOC) in Darmstadt, Germany
Muelhaupt said the odds of a particular individual being injured by the debris are minuscule, on the order of six chances in 10 trillion.
By comparison, you’re about 5,500 times more likely to win the Mega Millions jackpot, which has odds of 1 in 303 million.
CHINA’S 5B LONG MARCH ROCKET
On Sunday (July 24), China launched a new module for its space station on a Long March 5B rocket.
Unfortunately, the rocket’s propellant, which weighs 22 metric tons (about 48,500 pounds), has already reached a low orbit and is expected to return to Earth.
Aerospace Corporation says the rocket’s booster will re-enter Earth’s atmosphere at 1:15 p.m. ET Saturday, with an hour or so either way.
The Aerospace Corporation said there is “a non-zero probability” of the debris landing in a populated area, meaning it’s not impossible for it to happen.
However, the odds of anyone on the planet being injured are much lower, roughly one in 1,000 to one in 230, and well above the internationally accepted casualty risk threshold of one in 10,000 , Muelhaupt told reporters.
Part of the 21-ton Long March 5B rocket may not burn up completely when it re-enters Earth’s atmosphere.
It would then fall to the surface in an uncertain location and at high speed: several hundred miles per hour.
That’s what happened in May 2020, when fragments of another Chinese Long March 5B landed in Ivory Coast, damaging several buildings in the West African nation, although no injuries were reported .
Most spacefaring nations take precautions to avoid uncontrolled reentry, a lesson learned after large chunks of NASA’s Skylab space station fell from orbit in 1979 and landed in Australia.
China’s rocket problem is rooted in the risky design of the country’s launch process.
Typically, discarded booster stages re-enter the atmosphere shortly after liftoff, on a planned trajectory to discard them over water, and do not enter orbit.
However, the Long March 5B booster enters orbit and has no mechanism to control its descent as the orbit decays.
The falling shape of China’s Tiangong-1 space station can be seen in this radar image during its uncontrolled re-entry in 2018
Debris from American spacecraft has fallen to Earth before, but usually only in catastrophic disasters. Above, debris from the space shuttle Columbia is seen in 2003 after it broke up on re-entry, killing all seven astronauts on board.
Ultimately, the rocket body will disintegrate as it plunges through the atmosphere, but it is large enough that numerous pieces will likely survive a fiery re-entry in the debris shower on Earth’s surface.
China has previously rejected accusations of irresponsibility, with the Chinese Foreign Ministry saying the likelihood of harm to anyone or anything on the ground is “extremely low”.
Many scientists agree with China that the odds of the debris causing serious damage are minuscule, though others think launch designs like the Long March 5B pose an unnecessary risk.
Last May, one of the country’s Long March 5B rockets broke up on re-entry over the Indian Ocean, north of the Maldives.
Long March 5B had sent Tianhe, the first building block of China’s new space station, into orbit in April.
There were concerns that it might crash into a populated area on land, though it eventually fell into the ocean.
NASA Administrator Bill Nelson criticized Beijing, insisting it was “critical” that China and other countries “act responsibly and transparently in space.”
“Space nations must minimize risks to people and property on Earth from incoming space objects and maximize transparency regarding these operations,” he wrote in a statement.
The Wenchang Space Launch Center, from which the Wentian Module was launched on July 24, is a rocket launch site on Hainan Island, China.
Wentian, a research laboratory dedicated to science and biology experiments, has already docked with the main body of the space station, called Tianhe.
It will be followed by a second research laboratory module, Mengtian, which will be launched in October this year.
When Mengtian joins the rest of Tiangong, construction of the space station will finally be complete, although Beijing also plans to launch Xuntian, a space telescope that would co-orbit with the space station, in 2024.
Tiangong (meaning “heavenly palace”) will rival the aging International Space Station (ISS), which is operated by the space agencies of the US, Canada, Russia, Japan and Europe.
It will consist of three modules, although two other spacecraft, Shenzhou and Tianzhou, carrying crew and cargo respectively, can also dock at the station.
Once completed, the Tiangong space station will weigh about 66 tons, much smaller than the ISS, which launched its first module in 1998 and weighs about 450 tons.
It is expected to have a useful life of at least 10 years.
TIANGONG: CHINA’S NEW SPACE STATION COMPRISING THREE SEPARATE MODULES AND TWO ROBABLE SPACECRAFT
China’s space station is called “Tiangong”, which means “Heavenly Palace”.
Tiangong consists of several different modules that are being released one by one.
In April 2021, the core module, called “Tianhe”, was released. The first crew arrived at Tianhe two months later.
In July 2022, Wentian, a smaller module where research experiments will be conducted, attached to Tianhe.
In October 2022, a second research laboratory module, Mengtian, will also be attached to Tianhe. When it does, Tiangong Space Station will be complete.
Two other spacecraft that can dock at the station, Shenzhou and Tianzhou, carry crew and cargo, respectively, and are not considered part of the station itself.
China also plans to launch Xuntian, a space telescope that would co-orbit with the space station, in 2024.
3D rendering of the Chinese Space Station, or Tiangong Space Station, as it will look when fully built. Tianhe will form the main living quarters for three crew members. Shenzhou is an existing spacecraft that would dock at the station with the crew. Tianzhou is an existing cargo transport spacecraft