China will see the longest total solar eclipse in 500 years on July 22, a scientist said Saturday.

The prime time of the total eclipse was expected to begin from 9 a.m. to 9:38 a.m. (Beijing Time), said Wang Sichao, a research fellow with the Nanjing-based Purple Mountain Observatory under the Chinese Academy of Sciences.

"The total eclipse will last up to six minutes, or the longest one that can be seen in China in almost 500 years from 1814 to 2309," Wang said.

He said viewers in parts of 11 provinces in China's southwestern, central-southern and eastern areas, such as Tibet, Hunan and Jiangsu, will be able to witness the total solar eclipse, while in most parts of Shanghai, viewers can see the spectacular phenomenon.

For viewers in other provinces, including Beijing, they can observe a partial eclipse, he said.

A solar eclipse occurs when the moon is caught between the sun and the earth while each of them moves along their fixed orbits.

In a total solar eclipse, the sun, the moon and the earth are directly aligned as the sun swings into the cone of shadow cast by the moon.

Wang said the next total solar eclipse that can be seen in China will fall on March 20, 2034.

"But it can only be seen remote provinces, such as Tibet and Qinghai. It cannot not be compared with the upcoming one -- in terms of duration and number of cities that can see the eclipse," he added.

The last total solar eclipse visible in China took place on Aug. 1 last year. It was observed in northwest China and lasted two minutes in Yiwu County of northwestern Xinjiang Uygur Autonomous Region, the best place to see the phenomenon.

(Xinhua News Agency June 14, 2009)