Shenzhou XIV mission blasts off

In the second half of their mission period, the Tianzhou 5 cargo craft and the Shenzhou XV crew are scheduled to arrive at the massive station. The Shenzhou XIV and XV crews will meet inside the Tiangong and work together for a short time before Chen's crew flies back to Earth in December, the official said.

Before them, the Shenzhou XII and XIII crews, both with three members, lived inside Tiangong, which is travelling in a low-Earth orbit about 400 kilometers up. The Shenzhou XIII crew returned in mid-April.

In early May, the Tianzhou 4 cargo spacecraft was launched by a Long March 7 rocket from the Wenchang Space Launch Center in Hainan province, transporting nearly 6 metric tons of propellants and materials to the station.

Tiangong is expected to operate for up to 15 years and will serve as a scientific platform, space officials have said, noting it will also be open to foreign astronauts.

In April 1971, the former Soviet Union became the first in the world to operate a space station with the deployment of its Salyut 1 station in low-Earth orbit. Since then, 10 space stations have been launched, most built by the Soviet Union.

Before Tiangong, the only operational station was the International Space Station, a joint effort by several national space agencies including the United States' NASA and Russia's Roscosmos. China was excluded from the project mainly due to US objections.