The Shenzhou spaceship has three main modules - the orbital module, the re-entry module and propellant module - plus an extra section.

The orbital module is for the astronaut to live in and to use in carrying out his scientific experiments during the flight while in earth orbit. There-entry module is where he stays during the launching period and when returning to the earth, while the propellant module is to offer power for the craft and to control its position, change its orbit and return it to earth.

Lying at the forefront of the spacecraft, the orbital module is an air proof columniform structure equipped with solar cells on both sides, and solar sensors with all sorts of antennae on its exterior.

The orbitor is fixed with a docking port if docking maneuvers are required. If no docking is planned an extra segment is attached.

The uniqueness of the craft lies in its orbital module, which has multiple functions: It becomes a sitting room for astronauts during their flight, a testing cabin when they do experiments, a targeting aircraft when they seek to dock to other craft, an air brake when astronauts stroll outside, and, a hold when the craft is returning.

Conditions for life in the Shenzhou V are similar to that on earth, a senior expert was quoted yesterday by Xinhua as saying.

While in space, the astronaut works, eats and sleeps in the orbital module, according to Su Shuangning, a chief designer for the astronaut system under China's space flight programme.

"The onboard life support system creates an intra-module environment about the same as on earth,'' the expert said.

Elaborating, he said the astronaut system is fitted with sub-systems for air pressure, ventilation, sterilization, temperature and humidity. These ensure normal temperature, moisture and air pressure, including the pressure of oxygen and carbon dioxide, inside the two modules.

Shenzhou V operates primarily on preset programming, meaning that the astronaut plays a supplementary role in monitoring the flight and in controlling and running the spaceship in the course of the flight.

His task is to observe and record the conditions of the orbiting spaceship for the ground control centre.

The Shenzhou spaceship is distinct from the first manned spaceship of the former Soviet Union and the US in terms of its structure.

The Vostok spacecraft, the craft that contained Yuri Gagarin, the former Soviet Union cosmonaut and the first one in human history, and the Freedom 7 Mercury spacecraft, the one that contained Alan Shepard, the first US astronaut, both had two modules, while the Shenzhou spaceship has three.

In the first space flight, Vostok only circled around the earth for one time and the Mercury craft conducted a suborbital flight.

The Chinese astronaut, in comparison, is due to spend nearly one day along a low earth orbit.

In the aspect of power supply, the Shenzhou spaceship mainly uses solar cells, which is an advancement compared with the power supply systems on the Mercury and Vostok spaceships.

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