China successfully launched Wentian, the second module of the space station Tiangong, which the Asian giant is building in orbit. The launch took place on Sunday afternoon local time. After 13 hours, the module was docked to the station.

The Wentian module contains scientific equipment that will allow Chinese astronauts to conduct various scientific experiments while on the station. It will also provide three additional sleeping places and has another gateway for entering outer space.

The module became the largest object ever launched by China into orbit. It was also delivered by China’s largest Long March 5B rocket.

“This should be a historic moment. China’s largest carrying rocket today successfully launched the heaviest, longest and arguably the most important craft in the country’s space history. The mission was well fulfilled, which is very exciting and exhilarating,” says Li Dong, the rocket’s chief designer.

Now scientists are concerned about where the remains of the rocket that delivered the module into orbit will fall. While most of them safely dump the lower stages into the ocean, this type works differently. It delivers the payload by launching the entire first stage into Earth orbit and provides no way to control its motion as the rocket begins to fall to Ea”rth.

Currently, it is impossible to determine exactly where the 21-ton rocket will fall. Scientists continue to monitor it.

We remind you that in June China sent three astronauts, including one woman, to Tiangong to prepare the station for the arrival of the second and third laboratory modules. The last Wentian module should arrive at the station in October. With it, the station will acquire the final T-shaped shape.