/Chinese Rocket Debris Expected to Tumble Into Earth’s Atmosphere This Weekend

Chinese Rocket Debris Expected to Tumble Into Earth’s Atmosphere This Weekend

A Chinese rocket booster is hurtling toward Earth and it is still unclear where its pieces may land. The debris, which is expected to re-enter Earth’s atmosphere Saturday or Sunday, might be some of the largest ever to descend from orbit in an uncontrolled re-entry.

While much of the rocket booster is expected to break up upon re-entry, pieces, weighing up to 200 pounds, could reach the Earth’s surface and possibly land in an inhabited area, according to astronomer Jonathan McDowell at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.

Altitude of China’s rocket as it circles Earth before making re-entry

Estimated re-entry

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Estimated re-entry

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Estimated

re-entry

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Estimated

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Despite its size, experts said it is unlikely that pieces could actually hit someone as most of the Earth’s surface is water.

The Long March 5B, which was launched on April 29, ferried the first piece of China’s new space station into orbit. Typically, the boosters that propel rockets fall back to Earth in a predicted area. The Chinese rocket booster reached the upper limits of the atmosphere and began circling in orbit. Gravity has slowly been dragging it down since and once it re-enters Earth’s atmosphere, it should fall toward the planet’s surface, according to the Aerospace Corporation, a nonprofit federally funded space research center.

Top portion of rocket contains the space station module and additional rocket designed to thrust it into orbit

Core booster propels the rocket into upper atmosphere and typically returns to Earth in a predictable re-entry

Four additional boosters jettisoned after launch

The core booster typically separates once a high altitude is reached and falls back to Earth

About the height of a 10-story building

In a typical two-stage launch, the first stage launcher is discarded after a few minutes and falls in a generally predictable area. The lighter, upper stage continues until it reaches orbit.

Top portion of rocket contains the space station module and additional rocket designed to thrust it into orbit

Core booster propels the rocket into upper atmosphere and typically returns to Earth in a predictable re-entry

Four additional boosters jettisoned after launch

The core booster typically separates once a high altitude is reached and falls back to Earth

About the height of a 10-story building

In a typical two-stage launch, the first stage launcher is discarded after a few minutes and falls in a generally predictable area. The lighter, upper stage continues until it reaches orbit.

Top portion of rocket contains the space station module and additional rocket designed to thrust it into orbit

Core booster propels the rocket into upper atmosphere and typically returns to Earth in a predictable re-entry

Four additional boosters jettisoned after launch

The core booster typically separates once a high altitude is reached and falls back to Earth

About the height of a 10-story building

In a typical two-stage launch, the first stage launcher is discarded after a few minutes and falls in a generally predictable area. The lighter, upper stage continues until it reaches orbit.

Top portion of rocket contains the space station module and additional rocket designed to thrust it into orbit

Core booster propels the rocket into upper atmosphere and typically returns to Earth in a predictable re-entry

Four additional boosters jettisoned after launch

About the height of a 10-story building

The core booster typically separates once a high altitude is reached and falls back to Earth

In a typical two-stage launch, the first stage launcher is discarded after a few minutes and falls in a generally predictable area. The lighter, upper stage continues until it reaches orbit.

The core booster stage is currently circling Earth at about 17,000 miles an hour, or about one revolution around the planet every 90 minutes. The part falling back to Earth is estimated to be about 16 feet in diameter, 100 feet tall, and weigh 20 tons, according to orbit.ing-now, a website tracking the re-entry. Debris re-entry could happen as far north as Chicago, New York City, Rome or Beijing, or as far south as New Zealand or Chile, according to the Aerospace Corporation.

Its exact entry point into the Earth’s atmosphere can’t be determined until within hours of its re-entry, which is expected around May 8, the U.S. Space Command’s website said Tuesday. Spokesperson Maj. AnnMarie Annicelli said at this time “we can’t assess the likelihood of the object breaking up upon re-entry. There are too many factors to take into account this early, such as the atmospheric conditions and the exact angle of the object as it enters the atmosphere.”

The Long March 5B’s re-entry will be the first spacecraft weighing over 11 tons to make a deliberate uncontrolled re-entry since 1990, according to Dr. McDowell.

In May 2020, the re-entry of a similar Long March 5B rocket booster dropped piping from the fuel system in Ivory Coast. The booster flew directly over Los Angeles and New York City just minutes before ultimately crashing in the Atlantic. Locals in Ivory Coast found 30-foot long metal rods, causing minor damage to houses, but no reported casualties, according to Dr. McDowell.

In March this year, a SpaceX Falcon 9 rocket lit up the skies over Oregon and Washington as it re-entered, but that wasn’t a deliberate re-entry. Debris was found in Washington state.

Debris from a SpaceX rocket lit up the sky over Vancouver, Wash., in March.



Photo:

Roman Puzhlyakov/Associated Press

A spokesman for China’s Foreign Ministry said Friday in Beijing that authorities are watching the development and played down the risks. “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,” spokesman

Wang Wenbin

told a regularly scheduled briefing.

Jen Psaki,

the White House press secretary, on Wednesday said the U.S. “is committed to addressing the risks of growing congestion due to space debris and growing activity in space. And we want to work with the international community to promote leadership and responsible space behaviors.”

The module just sent into orbit will serve as the control hub of the space station and will be able to dock up to three spacecraft at a time, according to a Chinese government website. China has more launches planned to complete the station by the end of 2022.

China’s Tianhe space station core module at an air show in Zhuhai, China, in 2018.



Photo:

Long Wei/Zuma Press

Write to Alberto Cervantes at Alberto.Cervantes@wsj.com

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