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A girl adjusts a telescope at the Hangzhou Senior High School in Hangzhou, east China's Zhejiang province, July 15, 2009. Three students from the high school travelled 1,400 kilometers over the last two years along the line of total eclipse on July 22 within China to produce a guide that international astronomers used to select the best sites for viewing. The guidebook was adopted by the IAU and other astronomical organizations. Next week's event will be the longest total solar eclipse of the 21st century and is expected to about 6 minutes and 30 seconds. The eclipse will pass over 42 cities in China's populous Yangtze river valley. [Xinhua]