BEIJING -- Fuel has been injected into the Long March II-F T1 carrier rocket in preparation for the launch of the Tiangong-1 space module on Thursday night as planned, a spokeswoman for China's manned space program said on Wednesday.

Tiangong-1, or Heavenly Palace, is scheduled to blast off between 9:16 pm and 9:31 pm from Jiuquan Satellite Launch Center in Gansu province. The launch will mark the start of China's first spacecraft rendezvous and docking mission, Wu Ping said at a news conference.

The unmanned spacecraft will be sent into an orbit some 350 kilometers above Earth for in-orbit testing.

Experts will need some 40 minutes after launch to judge whether Tiangong-1 is functioning properly.

This is because when it enters orbit and deploys its solar panel, some 10 minutes after the launch, it will be on the dark side of Earth. It will be another 30 minutes or so before ground control can gauge if all systems are working, said Sheng Jie, deputy chief engineer of the Jiuquan Satellite Launch Center.

Wu explained the technicalities behind the rendezvous and docking maneuvers, vital procedures for any space station program.

According to the plan, Tiangong-1 will descend to a 343 kilometer orbit days prior to the launch of the unmanned Shenzhou VIII spaceship in early November. Two days after the Shenzhou VIII launch, the two craft will rendezvous and dock for the first time. They will stay docked for 12 days before decoupling. A second rendezvous and docking will be conducted some time later this year.

Shenzhou VIII will then return to Earth somewhere in the Inner Mongolia autonomous region.