Huge Chunk of Chinese Rocket Expected to Crash to Earth Sunday

Pieces of debris from China's Long March 5B rocket, which was launched on July 24, are due to crash-land somewhere on Earth on July 31.

The rocket was launched from Hainan province in order to deliver the solar-powered Wentian experiment module to China's Tiangong Space Station.

Rockets need a huge amount of fuel to escape Earth's gravity, which requires massive tanks to store. Once a rocket uses up all the fuel in its first stage, the empty rocket part is ejected to remove the extra weight, generally burning up as it hits the Earth's atmosphere at high speeds. However, due to the large size—measuring 176 feet tall, and weighing over 23 tons—of the Long March 5B, not all of the rocket will burn upon re-entry, with chunks being due to crash to Earth. Exactly when and where the debris will fall is difficult to predict.

long march 5b rocket
Stock image of a previous Long March 5B rocket launch on China's southern Hainan island on May 5, 2020. Chunks of a recent rocket are predicted to crash-land on Earth on July 31. STR / AFP / Getty Images

"Our current prediction places the re-entry at 07:52 UTC [3:52 a.m. ET] on Sunday, July 31, plus or minus 21 hours, with a predicted re-entry window in the North Atlantic Ocean. We will be updating this information in real time throughout the re-entry event," Marlon Sorge, technical fellow and executive director of the Center for Orbital and Re-entry Debris Studies at the Aerospace Corporation, told Newsweek.

According to Sorge, it's too early to predict how much debris will survive the journey through the atmosphere and crash-land on Earth, but the general rule is to expect 20 to 40 percent of a large object's mass to reach the ground, depending on that object's design.

"With this re-entry, we would expect 5 to 9 metric tonnes to reach the ground," Sorge said. "Generally, for an upper stage, small and medium tanks and large engine components can survive more or less intact. The large tanks and the skin of this core stage are likely to come apart. We should also expect to see lightweight material such as insulation fall out. The melting point of those materials will make a difference."

There are fears that due to the unpredictable nature of the rocket debris re-entry, people may be injured and property may end up being damaged. Previous deorbits of Long March 5B rockets also resulted in seemingly random crash-landing sites: In 2021, a core stage fell into the Indian Ocean, and in 2020, debris including a 40-foot pipe fell onto two villages in the Ivory Coast, damaging several buildings.

Newsweek has contacted the China National Space Administration for comment

According to Sorge, despite the size of the re-entering debris, the risk to any given individual is very low.

"The risk to any individual from re-entry debris in any given year is ~1 per 100 billion," he said. "The risk of getting hit by lightning is 80,000 times greater. That said, this re-entry will occur between 41.5 deg N and 41.5 deg S latitudes, where the vast bulk of the world's population (88 percent) lives. Note that New York, Los Angeles, Beijing, Tokyo, and Rome are at risk, but Boston, Seattle, London, Paris, and Northern Europe are not. Even with such low risk statistics, it is high enough that the world must track this event and prepare."

The Center for Orbital and Re-entry Debris Studies at The Aerospace Corporation's estimate of the re-entry location of the Long March 5B rocket body. Possible re-entry locations lie anywhere along the blue and yellow ground tracks. The yellow icon indicates the location of object at midpoint of the predicted re-entry window Center for Orbital and Re-entry Debris Studies / The Aerospace Corporation/Aerospace

Authors of a 2022 Nature Astronomy paper said that while uncontrolled rocket re-entries present very low risk, they are preventable.

"Launch providers have access to technologies and mission designs today that could eliminate the need for most uncontrolled re-entries," they said in the paper.

"On the issue of uncontrolled rocket body re-entries, the states of the Global South hold the moral high ground: their citizens are bearing most of the risks, and unnecessarily so, since the technologies and mission designs needed to prevent casualties exist already."