Three Chinese astronauts have arrived safely at China’s new space station at the start of a three-month mission, marking another milestone in the country’s ambitious space program.

The Shenzhou-12 craft connected with the Tianhe space station module about six hours after Thursday’s take-off from the Jiuquan launch centre on the edge of the Gobi Desert.

About three hours later, commander Nie Haisheng, 56, followed by Liu Boming, 54, and space rookie Tang Hongbo, 45, opened the hatches and floated into the Tianhe-1 core living module.

“This represents the first time Chinese have entered their own space station,” state broadcaster CCTV said on its nightly news broadcast.

[Official] #Shenzhou12 astronauts: Nie Haisheng (middle), Liu Boming (right), and Tang Hongbo (left). (HD Photo from CNSA CMS). Spacecraft launch time: UTC 01:22, June 17. Launch site: Jiuquan. pic.twitter.com/4G9YojKjgt

— CNSA Watcher (@CNSAWatcher) June 16, 2021

The crew will carry out experiments, test equipment, conduct maintenance and prepare the station for receiving two laboratory modules next year.

The mission brings to 14 the number of astronauts China has launched into space since 2003.

All appears to have gone smoothly so far.

China’s leaders hope the mission will be a complete success as the ruling Communist Party prepares to celebrate the centenary of its founding next month.

The astronauts had earlier been seen off by the commander of China’s manned space program, uniformed military personnel and a crowd of children waving flowers and flags and singing patriotic songs.

They travelled in the Shenzhou-12 spaceship launched by a Long March-2F Y12 rocket that blasted off shortly after the target time of 9.22am (11.22 AEST).

The rocket dropped its boosters about two minutes into the flight followed by the coiling surrounding Shenzhou-12 at the top of the rocket.

After about 10 minutes it separated from the rocket’s upper section, extended its solar panels and shortly afterward entered orbit.

The mission is the third of 11 planned through next year to add the additional sections to the station and send up crews and supplies.

Two astronauts on those past missions were women, and while this first station crew is all male, women are expected to be part of future station crews.

A fresh three-member crew and a cargo ship with supplies will be sent in three months.

China is not a participant in the International Space Station, largely as a result of US objections to the Chinese program’s secrecy and close military ties.

However, China has been stepping up co-operation with Russia and other countries, and its station may continue operating beyond the ISS, which is reaching the end of its functional life.

China landed a probe on Mars last month that carried a rover, and earlier landed a probe and rover on the moon’s far side and brought back the first lunar samples by any country’s space program since the 1970s.

After the Tianhe was launched in April, the rocket that carried it into space made an uncontrolled re-entry to Earth, though China dismissed criticism of the potential safety hazard.

-AAP