The debris from a Chinese rocket is expected to crash land back on Earth this weekend with experts trying to work out exactly when and where the remnants will touch down.

The Long March 5B was launched on April 29 at the Wenchang Space Launch Center in China. It’s mission was to carry into orbit a module containing living quarters for a future Chinese space station.

But after completing that task, the body of the rocket is now circling Earth and will soon re-enter the lower atmosphere. The uncontrolled nature of its reentry has left experts concerned about the potential impact it could have when it lands. The large piece of space junk measures 98 feet long and 16.5 feet wide and it weighs 21 metric tons.

The federally-funded research firm The Aerospace Corporation posted a tweet late Friday saying its prediction for landing was eight hours either side of 4:19 GMT time on Sunday morning. It pinpointed an area near the north island of New Zealand as a possible reentry point, but said it could happen anywhere across large parts of the planet.

Chinese Foreign Ministry Spokesperson Wang Wenbin said at a press conference Friday that it was “common practice” across the world for the upper stages of rockets to burn up while reentering the atmosphere.

“China is following closely the upper stage’s reentry into the atmosphere. To my knowledge, the upper stage of this rocket has been deactivated, which means that most of its parts will burn up upon reentry, making the likelihood of damage to aviation or ground facilities and activities extremely low,” he said, according to a translation on the ministry’s website.

On Thursday, Secretary of Defense Lloyd Austin told reporters that the United States had no plans to shoot it down and was hopeful that it will land in a place where it won’t harm anyone.

“I think this speaks to the fact that for those of us who operate in the space domain, that there is a requirement — there should be a requirement to — to operate in a safe and — and thoughtful mode, and make sure that we take those kinds of things into — into consideration as we plan and conduct operations,” he said.

Indeed, it is common for rockets and pieces of space junk to fall back to Earth. Last year, an 18-ton Chinese rocket passed over Los Angeles and New York City’s Central Park before falling into the Atlantic Ocean.