The Long March 5B rocket’s core stage could fall from space any day now.

A large Chinese rocket is set to make an uncontrolled reentry back into Earth’s atmosphere, but it is not yet clear exactly where or when the debris will hit our planet.

China’s Long March 5B rocket is “unpredictably” falling back to Earth after launching a part of the new T-shaped Chinese space station on Thursday local time in Wenchang, according to SpaceNews. The 22.5-metric-ton Tianhe space station module is in its correct orbit after separating as planned from the core stage of the rocket, which is now expected to re-enter in a few days or about a week.

“It will be one of the largest instances of uncontrolled reentry of a spacecraft and could potentially land on an inhabited area,” SpaceNews said. That said, the more likely possibility is the core stage will fall in an uninhabited place like Earth’s oceans, which cover 70% of the planet. The odds of a particular individual being hit by space debris are exceedingly low, once estimated at 1 in several trillion.

Plotting the trajectory of this falling rocket stage is difficult, if not impossible because there are too many uncertainties involved in calculating the effect of the atmospheric drag on the core module. Earth’s atmosphere can expand or contract with solar activity, making it hard to estimate exactly when and where the rocket will come down.

“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, adding that the object’s orbital inclination of 41.5 degrees means it “passes a little farther north than New York, Madrid and Beijing and as far south as southern Chile and Wellington, New Zealand, and could make its reentry at any point within this area.”

SOURCE SPACE.COM