It will later set up a permanently manned space station.

Zhang Qingwei, the president of the China Aerospace Science and Technology Corp, said China is developing a new family of powerful launch vehicles to propel a 20-ton space station.

China plans to launch its manned station "at an appropriate time this century," Zhang said. But he declined to give a solid time frame for the launch.

China's four unmanned test spacecraft were all sent into orbit atop the corporation's Long March 2F rockets.

But the new launchers will be built according to a modular design based on three models from the core stages -- 2.25 meters, 3.35 meters and 5 meters in diameter. Chinese researchers are also working to produce China's own liquid hydrogen, liquid oxygen and refined kerosene to produce a powerful propulsion fuel that will leave no pollutants or toxins, he said.

China launched its manned space program in 1992 -- made up of seven systems.

The country's manned mission has four goals: to develop basic manned space flight technology; observe the Earth and undertake experiments in space; help design space vehicles; and accumulate experience for a large space station.

Participating in the research, construction and testing of these systems are thousands of scientists and technicians from more than 3,000 organizations.

Thanks to their concerted efforts, China has mastered vital space technology, developed advanced carrier rockets and spacecraft and built a spaceship application system. These are among the country's highest scientific and technological achievements.

Chinese scientists are conducting a series of feasibility studies for a possible moon exploration program, according to Ouyang Ziyuan, the program's chief scientist and a senior member of the Chinese Academy of Sciences.

The scientists hope that they will one day be able to look for valuable resources and examine the environment and geological structure of the moon, Ouyang said.

Apart from abundant and stable solar energy on the moon's surface, the helium-3 isotope in the moon's regolith -- the layer below its surface level -- is particularly valuable. An isotope scarcely found on earth, helium-3 could be used to generate energy through nuclear fusion without causing waste.

But China's short-term goal is to carry out unmanned probes and it will only consider carrying out manned lunar landing after its manned space flight technology improves, Ouyang said.

He said that he and other scientists hope to witness lunar missions before the end of this decade.

(China Daily January 16, 2003)