Chinese officials cannot accurately say where space rocket debris from the recent launch of a space station module into low orbit would land on earth.
A Long March 5B rocket launched from China late last week. The rocket carried a 22.5-ton Tianhe space station module before it separated from the core stage as planned and is reportedly making an uncontrolled reentry into the planet's atmosphere within this week.
Experts said the rocket will be one of the largest uncontrolled reentries in history. Other notable large debris atmospheric reentries over the past decade include Europe's Gravity field and steady-state Ocean Circulation Explorer and China's Tiangong space station.
Rocket scientists said the debris could potentially land on an un inhabited area, such as the Earth's oceans, which cover more than 70% of the planet. However, there is still a small chance that it could hit a residential area. Scientists said the chances of the debris hitting a person would be 1 in several trillion.
Scientists said accurately plotting the trajectory of the spent rocket is nearly impossible as there are too many factors to consider. These include factors such as wind speeds, temperature, solar activity, the state of the rocket and atmospheric drag.
"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.
SpaceNews said an orbital inclination of 41.5 degrees means that the rocket could end up as far north as New York or as far south as New Zealand. The news outlet said the rocket could make a reentry at any point within this area in the next few days to about a week.
Rocket scientists generally try their best to point falling debris to uninhabited areas but the entire effort is only an estimation. Most of the debris does burn up in the atmosphere but large pieces can still make their way to the ground.
Harvard University astrophysicist Jonathan McDowell, who helped plot the uncontrolled return of NASA's 76-ton Skylab space station in 1979, said even the best estimates could be off by hundreds of kilometers.