The Shenzhou-14 spaceship has docked with Tianhe, the core module of China's space station, and the three Chinese astronauts aboard entered the core module. 

The spaceship successfully conducted a fast automated rendezvous and docked with the radial port of the space station's core module Tianhe, the port facing the Earth, after autonomously changing its orbit six times, at 5:42 p.m. Beijing Time, said the China Manned Space Engineering Office (CMSEO).

The whole process of docking took approximately seven hours.

After docking, the trio conducted environmental tests and entered the Tianzhou-4 cargo craft at 12:19 p.m. Beijing Time. The cargo ship, launched on May 10, carries six months of living supplies for taikonauts, spare parts for space station maintenance and space research equipment.

"This time, it docked from the radial, or the most challenging position. But we've performed well. We consider the technology stable and established," Gao Xu, deputy chief designer of the Shenzhou manned spaceship system of China Academy of Space Technology, told CGTN.

Gao said the combination is in great condition to assemble the space station.

The three taikonauts opened four capsule hatches before they entered the core module of the space station.

Later they entered the space station's core module successfully, embarking on their upcoming six months trip in space.

The priority of the Shenzhou-14 crew is to activate the essential systems for human living such as oxygen recycling, drinking water and the sleeping environment, said Wang Saijin, deputy chief designer of Beijing Aerospace Control Center (BACC) in a previous interview.

"In the following week, the taikonauts will open the hatches of two cargo spacecraft, Tianzhou-3 and Tianzhou-4, to organize and move around the supply packages for future use," said Wang, "but first they deserve some rest."

Challenging and eventful mission

The Shenzhou-14 crewed spaceship atop the Long March-2F Y14 carrier rocket took off at 10:44 a.m. Beijing Time on Sunday from Jiuquan Satellite Launch Center in northwestern China.

Read more about the launch of Shenzhou-14 mission

The CMSEO later declared the launch a complete success after the spaceship separated from the rocket and entered its designated orbit.

This is the 23rd flight mission since the approval and launch of the country's manned space program, and the third crewed mission for China's space station project.

The Shenzhou-14 spaceship carries the mission's commander Chen Dong, other two taikonauts Liu Yang and Cai Xuzhe. They will cooperate with the ground team to complete the assembly and construction of the Tiangong space station. 

The tasks for the three-member crew will be the most complicated and challenging so far, according to Huang Weifen, chief astronaut system designer of the Astronaut Center of China.

The space station will be developed from a single-module structure into a basic three-module structure, consisting of the core module Tianhe currently orbiting the Earth and the upcoming two lab modules Wentian and Mengtian.

Wang said two great achievements will make this mission so special.

"One is we will witness the completion of three-module space station combination," he said, "and the other is when the crew of Shenzhou-14 and the upcoming Shenzhou-15 meet up in the space station."

The Shenzhou-14 crew will stay in space for six months. The separate lab modules are scheduled to arrive in July and October separately, followed by the Tianzhou-5 cargo craft and the Shenzhou-15 crewed spaceship later this year.

CGTN's Cao Qinging, Sun Ye, Li Qian, Zhao Chenchen, Geng Xiuhui and Gong Zhe also contributed to the story.