China is about to launch its fourth manned space mission and is sending a crew of three, including the nation’s first female astronaut, to the orbiting Tiangong space lab.
Chinese Shenzhou-9 capsule is set to lift off from the Jiuquan spaceport on the edge of the Gobi desert at 18:37 local time (10:37 GMT).
A Long March 2F rocket will put the astronauts on a path to dock with Tiangong in a couple of days’ time.
They will then spend over a week living and working in orbit before returning to Earth.
The mission is commanded by Jing Haipeng, who is making his second spaceflight after participating in the Shenzhou-7 outing in 2008 – the mission that included China’s first spacewalk.
Jing Haipeng’s flight engineers are both first-timers.
Liu Wang, a People’s Liberation Army fighter pilot, has got his chance after spending 14 years in the China National Space Administration’s astronaut corps.
Liu Yang, on the other hand, has emerged as China’s first woman spacefarer after just two years of training.
Her role in the mission will be to run the medical experiments in orbit.
Shenzhou-9 follows on from the unmanned Shenzhou-8 venture last year that tested the technologies required to join a capsule to the Tiangong lab.
Those manoeuvres went very well and gave Chinese officials the confidence to send up humans.
When it arrives at Tiangong, the Shenzhou-9 craft is expected to make a fully automated docking, but there is a plan to try a manual docking later in the mission.
This would see the crew uncouple their vehicle from the lab, retreat to a defined distance and then command their ship to re-attach itself.
Liu Wang will take the lead in this activity.
“We’ve done many simulations,” he said during the pre-launch press conference.
“We’ve mastered the techniques and skills. China has first class technologies and astronauts, and therefore I’m confident we will fulfill the manual rendezvous.”
Tiangong is the next step in a strategy that Beijing authorities hope will lead ultimately to the construction and operation of a large, permanently manned space station.
It is merely the prototype for the modules China expects to build and join in orbit. Mastering the rendezvous and docking procedures is central to this strategy.
At about 60 tons in mass, this proposed station would be considerably smaller than the 400-tonne international platform operated by the US, Russia, Europe, Canada and Japan, but its mere presence in the sky would nonetheless represent a remarkable achievement.
Concept drawings describe a core module weighing some 20-22 tons, flanked by two slightly smaller laboratory vessels.
Officials say it would be supplied by freighters in exactly the same way that robotic cargo ships keep the International Space Station (ISS) today stocked with fuel, food, water, air, and spare parts.
China is investing billions of dollars in its space programme. It has a strong space science effort under way, with two orbiting satellites having already been launched to the Moon. A third mission is expected to put a rover on the lunar surface.
The Asian country is also deploying its own satellite-navigation system known as BeiDou, or Compass.
Before leaving Earth, Liu Yang said the Shenzhou-9 mission would generate further pride in Chinese people.
“When I was a pilot I flew in the sky; now as an astronaut, I’m going into space. It’s higher and it’s farther,” she said.
“I have a lot of tasks to fulfill, but besides these tasks I want to feel the unique environment in space and admire the views. I want to explore a beautiful Earth, a beautiful home.
“I want to record all my feelings and my work, to share with my friends, and my comrades and my future colleagues.”