The three successful test launches of unmanned spacecraft Shenzhou (Divine Vessel) since 1999 have taken the country closer to the firmament, say scientists.

A dozen pilots are getting ready to make history as China's first astronauts, said Wang Zhuang and Zheng Songhui, the two deputy general designers of Shenzhou III, recovered on April 1 after its successful launch.

The dauntless dozen, picked from among thousands of air force pilots, are undergoing intensive training, the two scientists said at the opening seminar of Beijing National Science and Technology Week that concluded on May 26. If Shenzhou IV's (unmanned) test flight is successful, China could send a manned flight into outer space by 2005, they said.

But the space authorities haven't given a specific date for the Shenzhou IV flight. Nor have they said how many more tests were needed before a manned flight could be launched.

But the chief engineer of China's manned space programme, Wang Yongzhi, said China needed "several (more) unmanned test flights to raise the dependability and safety levels".

"We will begin our manned spaceflights when our rockets and space capsules become dependable ... when safety can be amply ensured and when our pilots can safely take off and return," Wang said. "I don't think this will take a long time," he said on China Central Television (CCTV) a day after the Shenzhou III was recovered.

A research scientist with Shanghai Academy of Space Flight Technology, Liu Zongying, trained the astronauts for sometime in Beijing. The chief designer of Shenzhou's propulsion section said China's first batch of astronauts consisted of 14, and not 12, candidates; two of them were in Russia for training.

The height and weight of the pilots, all around 30 years, would surprise many people, Liu said. For, on an average they are 1.7 metres tall and weigh 50 kg. But contrary to popular belief that astronauts ought to be tall and well-built, shorter men can manoeuvre more flexibly in the limited room of the space capsule. Because in outer space, the 2.8-metre long orbital module, with a diameter of 2.25 metre, will be the main area of the astronauts' operations, he said.

The commander-in-chief and general designer of the country's manned space flight programme, Su Shuangning, said the short height of most Chinese, their speed and agility, and their diligence and endurance were advantages in astronaut training and manned space flights. The pilots' training has been progressing very well and they are undergoing a final series of physical and technical exercises.

As a Shanghai resident, Liu feels proud that his city designed the 36-square-metre solar panels for Shenzhou. These panels are capable of generating more power than the Russian models. A colour video transmission equipment, made in Shanghai too, will allow people on earth to monitor the inside of the spacecraft, he said.

Shanghai has also made a 1,200-square-metre parachute for the safe landing of the module on earth, he said.

But what will astronauts' everyday life be like? Liu said it's important that they maintain personal hygiene. They can even change their underwear - which are deposable - everyday. Their menu will have 20 types of food, compressed in bricks and toothpaste tubes.

Destination Moon

Once its manned space flight technology matures, China will send a manned spacecraft to the moon, said the chief scientist of China's moon exploration program, Ouyang Ziyuan. "China may be able to send a mission to the moon by 2010," the senior member of the Chinese Academy of Sciences said in Beijing last week.

"China's moon exploration program has undergone a painstaking feasibility study, and theoretically speaking, we are capable of conducting such a probe," the scientist said.

If approved by the government, the destination moon program will begin with the launching of a lunar orbiter by 2010, which will 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 3He isotope ("Helium 3") in the Moon's regolith - the layer below its surface level - is particularly valuable. An isotope scarce on earth, 3He could be used to generate energy through nuclear fusion without causing waste.

Just how powerful a source of energy 3He is can be gauged from the fact that 8 tons of the isotope can generate enough electricity that China uses in one whole year, he said. This is where the real significance of the moon program lies.

The maiden unmanned probe should cost no more than 1 billion yuan (US$120 million), Ouyang said, after which China will establish a moon base just as it did in the North and South Poles.

But China's short-term goal is to carry out unmanned probes and it will execute a manned lunar landing only after the advancement of its manned space flight technology becomes ripe, Ouyang said.

He hoped China could complete two lunar missions in the first decade of the century, but did not specify when the manned lunar landing would get the go ahead.

Ambitious Program

After sending its astronauts into space, China will launch space laboratories, to be manned by scientists for a short time, space program planners said. It will then set up a permanently manned space station.

The president of China Aerospace Science and Technology Corp (CASC), Zhang Qingwei, said China was developing a new family of powerful launch vehicles, to be used to propel a 20-ton, permanently manned space station.

China plans to launch its manned station "at an appropriate time this century", Zhang said, declining to give a timeframe for the launch.

The three test spacecraft were sent into orbit atop CASC's Long March 2F rockets. But the new launchers will be built on a modular design based on the three models of the core stages - 2.25 meters, 3.35 meters and 5 meters in diameter - powered by liquid hydrogen, liquid oxygen and refined kerosene, which produces powerful propulsion but leaves no pollutants or toxins, he said.

The country's launch vehicle is equipped with an escape and fault detecting and handling system, guaranteeing the safety of the astronauts, he said.

China launched its manned space program in 1992 - made up of seven systems, including those of astronaut and spacecraft scientific application and a landing field, said a spokesman for the program. The country's manned mission has four goals: breakthrough of basic technology of manned space flight; space observation of the earth, and space scientific and technological experiment; design of space vehicles and; accumulation of experience for large space station.

Participating in the research, building and testing of these systems are thousands of scientists and technicians in more than 3,000 organizations, the spokesman said. Thanks to their concerted efforts, China has mastered some vital space technologies, developed advanced carrier rockets and spacecraft and built a spaceship application system. These are among the country's highest scientific and technological achievements.

(China Daily May 30, 2002)