China successfully launched its Shenzhou 8 spacecraft early Tuesday morning, marking a key step toward fulfilling the country's dreams of establishing its own space station.

The spacecraft is due to dock with the Tiangong-1 space lab module early Thursday morning. The Tiangong-1 was sent into space in late September.

The rendezvous and docking between Shenzhou-8 and Tiangong-1 are pivotal, as the procedures are a must for the construction of a permanent manned space station, which China hopes to build around 2020.

China has succeeded in launching seven spacecraft and sending six astronauts into space since 1999, building up experience for the launch of the Shenzhou-8, as well as the planned launches of the Shenzhou-9 and -10 in 2012.

The country's first spacecraft, the Shenzhou-1, was launched in November 1999, heralding the beginning of China's foray into manned space exploration.

The main goal of the Shenzhou-1 launch was to examine the performance and reliability of the launch vehicle, a Long March-2F carrier rocket, and evaluate key space exploration technology.

"Within only seven or eight years, China's space experts have completed what their foreign counterparts took three to four decades to achieve," said Wang Yongzhi, the chief designer of the Shenzhou-5 and -6 spacecraft.

The Shenzhou-2 was China's first "formal" unmanned spacecraft. It was launched in January 2001, conducting experiments in the areas of materials science, astronomy and physics in a microgravity environment.

The Shenzhou-3, launched in March 2002, carried human physical monitoring sensors and "dummy astronauts." It was also equipped with escape and emergency rescue functions.

Successful tests aboard the Shenzhou-3 laid a firm foundation for the realization of manned flight, Wang said.

Nine months later, the Shenzhou-4 was launched, featuring radiation-proof facilities and manual emergency rescue systems, despite the fact that the vessel was unmanned.

The launch of the Shenzhou-5 in October 2003 was another milestone for China's manned space program, as the mission successfully sent astronaut Yang Liwei into space, making China the third country to send a man into space after the Soviet Union and the United States.

The Shenzhou-5 orbited Earth 14 times before bringing Yang back to Earth in good condition after 21 hours and 23 minutes in space.

Two years later, China conducted another manned spaceflight, this time sending astronauts Fei Junlong and Nie Haisheng into space aboard the Shenzhou-6. The astronauts carried out scientific and medical experiments onboard the craft.

China achieved its first spacewalk, conducted by astronaut Zhai Zhigang, with the launch of the Shenzhou-7 in September 2008. Zhai carried out the spacewalk for 19 minutes and 35 seconds while astronauts Liu Boming and Jing Haipeng remained inside the Shenzhou-7.

China thus became the third country in the world to conduct extravehicular activity in space, following the Soviet Union and the United States.

The first seven Shenzhou spacecraft were launched from the Jiuquan Satellite Launch Center in northwest China's Gobi Desert, using Long March-2F carrier rockets to launch all of the vessels. The Shenzhou-8 and Tiangong-1 were launched from the same center with upgraded launch vehicles.

China's efforts to achieve human spaceflight have been "slow-paced but steady," according to John Logsdon, a professor emeritus of political science and international affairs at George Washington University.

China will send the Shenzhou-9 and -10 for another two docking missions in 2012. At least one of the two spacecraft will carry astronauts.

Once China has mastered rendezvous and docking procedures, it will be armed with the capacity required for building a permanent space station, said Zhou Jianping, the current chief designer of China's manned space program.

"It will make it possible for China to carry out space exploration on a larger scale," Zhou said.