China will broadcast live the nation's maiden spacewalk slated for 4:30 PM on Saturday, according to Wang Zhaoyao, spokesperson with the manned space program.

The spacewalk, or extra-vehicular activity (EVA), will last about 30 minutes, he said at a press conference here Friday.

Excluding the opening and the closing of the module gate, the real spacewalk may take about 20 minutes, he said.

One of the three taikonauts aboard the Shenzhou 7 spacecraft, Zhai Zhigang, Liu Boming and Jing Haipeng, will conduct the spacewalk.

Wang said the duration might be adjusted according to the physical conditions of the taikonauts.

According to the schedule, the taikonauts would finish testing the space suits at 1:00 AM on Saturday when the Shenzhou 7 spacecraft has made 19 orbits around the earth, he said.

Then they would begin a 100-minute training in the orbital module before the EVA, he said.

As of 16:00 AM, the spaceship which blasted off at 9:10 PM on Thursday at Jiuquan Satellite Launch Center in the northwestern Gansu Province, has made 12 orbits around the earth as scheduled, wang said.

Physical conditions of the three astronauts who are in duty shift, all stay normal. They began their first sleep at 00:20 AM on Friday, Wang said.

During the mission, taikonauts would need to assemble and test the EVA suits, depressurize and repressurize the cabin, exit and re-enter the orbital module. The EVA includes two tasks of spacewalking and fetching a piece of experimental material fixed on the exterior surface of the orbital module.

Two taikonauts began to unpack and assemble the indigenous Feitian spacesuit at 10:20 AM on Friday in the orbital module while the other Jing Haipeng stayed in the re-entry module to keep a eyeon the vessel operation.

The taikonauts will wear two space suits, including Chinese Fetian and Russian Orlan.

Feitian, which literally means flying the sky, has 10 layers and weighs about 120 kilograms. The domestically-made suit costs 30 million yuan (about US$4.4 million), and takes up to 15 hours for astronaut to assemble and put on.

China spent less than four years in developing Feitian suit and its design and assembling were done by Chinese scientists independently.

A Russia company provides three Orlan suits, two low-pressure training suits, four suits for underwater training, and four sets of docking systems in the craft, according to a contract signed in April, 2004. The Chinese side is responsible for providing power and communications equipment for some of the EVA suits.

"EVA is a big leap for the manned space program," he said. China had made a series of technical breakthroughs, including the research and development of an EVA suit and an airlock module.

The process of extravehicular activities cannot be simulated completely on the ground and some of the newly developed products are to be tested in flight for the first time. Thus, The capability and skills of the taikonauts and the quality of their operations directly determine the result of the mission, he said.

If Shenzhou-7 mission is successful, China will become the third country after the United States and Russia to accomplish a spacewalk, a crucial capacity if China is to have its own permanent space station.

(Xinhua News Agency September 26, 2008)