Live television broadcast showed the astronauts in blue uniform waved to the camera inside the Tiangong-1 after they entered the cabin.

They are the first tenants in the 15-cubic-meter cabin of Tiangong-1, known as "Heavenly Palace."

The 8.5-tonne space lab module has been traveling around Earth for 263 days since it was launched in September 2011.

"The real test will be the manual docking attempt six days later," said Zhou Jianping, chief engineer of China's manned space program. "A manual docking, if successful, will demonstrate the country's grasp of essential space rendezvous and docking know-how."

"It will mean China is fully capable of transferring human and cargo to an orbiter in space," Zhou said.

A manual docking is considered as a major step forward in China's manned space program to build a space station around 2020, in time for the likely retirement of the International Space Station. (Xinhua)

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BEIJING, June 18 (Xinhua) -- The first manned space docking of China succeeded Monday afternoon with the coupling of the Shenzhou-9 spacecraft and Tiangong-1 lab module, the Beijing Aerospace Control Center said.

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