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China is beefing up its space monitoring network, and will locate its central command system powered by sophisticated homegrown technology in north China's Xi'an city, according to an industry source.

"The orbit error of China's spacecraft can be reduced to a little more than ten meters, compared to more than a hundred kilometers when space technology in China was still underdeveloped," Ce.cn, a Chinese economic portal website, quoted a space expert as saying.

He said climactic conditions affect the landing of recoverable satellites, meaning that vehicles may land several kilometers away from the predicted landing site, making it difficult to carry out post-landing satellite searches.

Since the "DFH" (Dongfanghong, or The East is Red) telecommunications and broadcasting satellites were launched in 1970, nearly a hundred spacecrafts of different categories have been sent into space by Chinese scientists.

A world-leading precise orbit calculation system, developed by Chinese space engineer Wang Jiasong, won a European space award in 2002. The system can monitor satellites very accurately, according to the space expert.

Chen Changgui, chief engineer of the Xi'an Satellite Monitoring Command Center, said its satellite experts hook up on a telecommuting system which enables them to monitor and diagnose satellite malfunctions round the clock.

In its nearly 40 years of existence, the center has dealt with more than a hundred satellite malfunctions through monitoring and forecasting, said Chen.

Scientists at the center successfully recovered China's first satellite re-entry module on Nov. 29, 1975 -- three days after its launch -- making China the third country in the world to master the technology, following the former Soviet Union and the United States.

China has launched 22 recoverable satellites and got back 21 of them after 30 years of space technological development.

(Xinhua News Agency December 12, 2006)