Scientists have warned that a massive piece of Chinese space junk is unpredictably orbiting Earth. As a result, the debris could fall a little farther on New York or another major city in the coming days.

"It will be one of the largest instances of uncontrolled reentry of a spacecraft and could potentially land on an inhabited area," SpaceNews said.

The 21-ton object is the central stage of one of China's largest rockets. In addition, the country has launched Long March 5B - its first space station module.

China Space Program
(Photo : Lintao Zhang/Getty Images)
(FILE PHOTO) China launches Long March 2F rocket to bring its first space lab, the Tiangong-1, to space.

Experts are expecting the remaining portion of the rocket to follow a predetermined route that would send it crashing into the ocean until the core component separated from the rest of the rocket.

Instead, it orbits unpredictably.

The news outlet said debris that survives re-entry into Earth's atmosphere could crash down in various locations. These could land in New York, Madrid, and Beijing in the Northern Hemisphere, and southern Chile and Wellington, New Zealand, in the Southern Hemisphere.

"The high speed of the rocket body means it orbits the Earth roughly every 90 minutes and so a change of just a few minutes in reentry time results in reentry point thousands of kilometers away," SpaceNews said

However, it is more likely that the core stage would crash into an uninhabited region, such as Earth's oceans, covering 70% of the world. The chances of a specific person being struck by space debris are minimal, once believed to be one in several trillion.

ALSO READ: NASA Roleplays Near-Earth Space Objects Passing By, Here's What Happened in the Asteroid Simulation 

Where is It Exactly Going to Land?

Space News added that an exact landing is challenging to foresee because of its current velocity - circling the Earth every 90 minutes.

However, the most likely scenario is that it would crash into the ocean or populated areas, which make up a significant portion of the predicted range.

Astronomer Jonathan McDowell said the extreme heat would likely obliterate large fragments during reentry to Earth; however, smaller pieces can make it to the ground.

"I think by current standards it's unacceptable to let it re-enter uncontrolled," McDowell told the outlet.

"Since 1990, nothing over 10 tons has been deliberately left in orbit to re-enter uncontrolled," he added.

McDowell also analyzed the Long March 5B's return and other significant debris cases, including NASA's 76-ton Skylab space station's uncontrolled return nearly 42 years ago. The space station was steered slightly over its scheduled reentry point over the Indian Ocean by ground controllers, but the debris track extended far further than anticipated.

The Long March 5B stage, on the other hand, is seven times much larger than the one on SpaceX's Falcon 9 rocket. As a result, Elon Musk's spacecraft reportedly caused debris to fall on a farmer's field in Washington state during reentry.

Chinese space officials launched the Long March 5B carrier rocket at the Wenchang Space Launch Center in the southern island province of Hainan last week.

It was transporting modules for the country's first permanent space station, which is expected to launch in 2022.

At least a dozen Chinese astronauts are preparing to live on the station right now.

The first of 11 missions to construct and equip the station, which is estimated to weigh 66 tons, was launched last week.

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