Out-of-control Chinese rocket will crash back to Earth on Saturday night

Tianhe1 Launch: The Long March 5B rocket that took the core module of the China Space Station to orbit.

The Long March 5B launched the China Space Station core module in April. The rocket is now spiraling back to Earth.

China News Service/Getty

The discarded body of a Chinese Long March 5B rocket is expected to slam into the Earth’s atmosphere on Saturday evening. The latest estimates suggest the rocket body, which is tumbling end over end as it hurtles around the planet, will land in the Pacific Ocean.

The US Pentagon has been tracking the rocket body since last week. Because of the unusual tumbling of the rocket body it’s been difficult to predict where — exactly — the huge piece of space junk will fall back to the ground. 

Aerospace.org has also been tracking the rocket, and as of Saturday afternoon was predicting that it would fall into the Pacific Ocean sometime between 6 p.m. and 10 p.m. PT, though predictions are changing quickly.

Want to see it? Gianluca Masi of Ceccano, Italy, managed to capture an image, which he shared on his Virtual Telescope Project 2.0 website.

At the time the image was taken, “the rocket stage was at about 700 kilometers (434.9 miles) from our telescope, while the sun was just a few degrees below the horizon, so the sky was incredibly bright,” Masi wrote. “This is huge debris (22 tons, 30 meters/98 feet long and 5 meters/16 feet wide), but it is unlikely it could create serious damage.”

In fact, Jonathan McDowell, an astrophysicist at the Astrophysics Center at Harvard University who tracks and catalogs satellite orbits, told CNN “the risk that it will hit you is incredibly tiny. And so I would not lose one second of sleep over this.” 

Because the Pacific Ocean covers so much of Earth, the debris will likely splash down in Pacific waters somewhere, he predicted.

The rocket helped launch Tianhe, the core module in China’s new, next-generation space station, on April 28. The space base is scheduled to be completed late in 2022 to serve as a scientific research outpost for China over the next decade, and it’ll be the only other operational space habitat aside from the International Space Station. 

How did this happen?

Typically, what goes up, must come down.

Back in 2018, similar events took place, when China’s out-of-control Tiangong-1 space station reentered the atmosphere over the ocean near Tahiti. No one was injured, and the debris either burned up or found a new home on the floor of the south Pacific.

When space agencies launch large rockets, they typically don’t reach orbit — they’re designed to fall back into the ocean. Other times, rockets and satellites have built in mechanisms to deliberately deorbit them and guide them back to Earth safely. Many have been deliberately tossed into the so-called “spacecraft cemetery,” a huge, uninhabited area of the Pacific Ocean. It’s one of the furthest locations on the planet from any land. 

The rocket that carried Tianhe made it into orbit and once its engines shut down, was captured by Earth’s gravity. Drag on the rocket sees its orbit slowly decay. Each rotation around the Earth brings it closer to a point where it ultimately slams into the atmosphere at speed — “reentry” — and burns up.  

However, it’s not just about what comes down. Space junk, discarded rocket boosters, scraps of metal and defunct satellites, can remain in orbit for years — even decades. Almost 3,000 satellites are in orbit and remain in operation, but almost three times that amount are defunct. 

“As we’ve launched more and more satellites into space, the problem has gotten progressively worse,” James Blake, an astrophysicist Ph.D. student at the University of Warwick studying orbital debris, told CNET last November.

As of April 5, McDowell suggests we still don’t know where the booster will come down but it’s return is likely to occur on May 8 or 9.

On April 6, U.S. defense secretary Lloyd Austin said the US doesn’t “have a plan to shoot the rocket down” and is hopeful it will “land in a place where it won’t harm anyone.”

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source: cnet.com