The Long March 5B rocket's descent will be "one of the largest instances of uncontrolled reentry" and could fall on an inhabited area, according to SpaceNews, although it is more likely to fall in an uninhabited area as most of the earth is uninhabited, with the odds of a person being hit by space debris sitting at about one in several trillion.
The first time the 30-meter long Long March 5B was launched, it nearly landed on US soil.
The location where and time when the rocket debris will land is impossible to predict as there are too many factors involved. The rocket is orbiting Earth about every 90 minutes, meaning even a change of just a few minutes in reentry time could lead to a change of thousands of kilometers in the location it will fall in.
Although parts of the rocket will burn up upon reentering the atmosphere, larger parts may survive the reentry.
The rocket passes a little north of New York, Madrid and Beijing and as far south as southern Chile and New Zealand, meaning that it could reenter at any point within this area, according to SpaceNews.
China launched an unmanned module last month containing what will become living quarters for three crew on a permanent space station that it plans to complete by the end of 2022, state media reported.
The module, named "Tianhe," or "Harmony of the Heavens," was launched on the Long March 5B, China's largest carrier rocket, at 11:23 a.m. (0323 GMT) from the Wenchang Space Launch Centre on the southern island of Hainan.
Tianhe is one of three main components of what would be China's first self-developed space station, rivaling the only other station in service - the International Space Station (ISS).
Tianhe forms the main living quarters for three crew members in the Chinese space station, which will have a life span of at least 10 years.
The Tianhe launch was the first of 11 missions needed to complete the space station, which will orbit Earth at an altitude of 340 to 450 km (211-280 miles).
In the later missions, China will launch the two other core modules, four manned spacecraft and four cargo spacecraft.
Reuters contributed to this report.