An annular eclipse of the sun is expected to cross China Friday afternoon, Cheng Zhuo, a researcher with the Purple Mountain Observatory under the Chinese Academy of Sciences, said Wednesday.

The astronomical phenomenon, predicted to be the longest annularity of the next 1,000 years, will be visible in some areas of Yunnan, Sichuan, Guizhou, Shaanxi, Hunan, Hubei, Henan, Anhui, Jiangsu and Shandong provinces as well as Chongqing municipality.

A partial eclipse would be seen in most of the rest of China, except for the northeast tip of Heilongjiang Province, said Cheng.

According to the National Aeronautics and Space Administration (NASA) of the United States, the annular eclipse of the sun will begin in Africa and pass through the Indian Ocean, where the maximum duration of annularity will reach 11 minutes and 8 seconds.

It will continue into Asia through Bangladesh, India, Myanmar and China. Chen said the annular eclipse will end at Jiaodong peninsula in China.

The longest duration of the annularity on China's territory would be 8 minutes and 17 seconds in Ruili, Yunan Province, Cheng said.

A sunset with the annular eclipse would be seen in some areas of Shandong, Guangdong and Taiwan, said Cheng.

An annular eclipse occurs when the moon does not cover the entire disc of the sun so that a ring of light encircles the shadow of the moon.

Wang Sichao, also of the Purple Mountain Observatory, said that though an annular eclipse was not considered as spectacular as a total solar eclipse and was of little value in scientific research, it was interesting for the general public to watch the astronomical phenomenon.

(Xinhua News Agency January 13, 2010)