A huge rocket body is moving around Earth uncontrollably, and it could fall back to Earth in the coming days. The rocket is said to be a 21-ton object and was a part of the core stage of China’s Long March 5b rocket.

Recently, the Chinese space agency launched the first module of its space station into orbit. Instead of falling into a pre-designated spot in the ocean, the Long March 5b’s core stage is orbiting Earth uncontrollably.

Rocket orbiting uncontrollably

The object can fall back on Earth sometime in the coming days, reports SpaceNews. “I think by current standards it’s unacceptable to let it reenter uncontrolled,” astronomer Jonathan McDowell told the news agency. “Since 1990 nothing over 10 tons has been deliberately left in orbit to reenter uncontrolled.”

The rocket stage is said to be 100 feet long and 16 feet wide, as per the report. While falling back, the Earth’s atmosphere might turn it to ashes, but large chunks of debris might survive and fall on the surface. Well, the debris is expected to land in the oceans, but it could still threaten inhabited areas.

“It is always difficult to assess the amount of surviving mass and number of fragments without knowing the design of the object, but a reasonable ‘rule-of-thumb’ is about 20-40% of the original dry mass,” Holger Krag of the ESA, told SpaceNews.

Construction still incomplete

The space station’s core module is called Tianhe that was placed in orbit aboard a Long March-5B Y2 carrier rocket. Tianhe is the first module of the space station and is the biggest spacecraft China has ever built. The launch will be followed by 10 more cargo and crew missions to complete the construction by the end of 2022.

The launches will include four crewed missions, two module launches, and four cargo missions. The space lab will take a T-shape with Tianhe at the center. China’s space station is built to last for at least 10 years, although it is believed to last for 15 years with maintenance and repairs.