Black hole sun

The eclipse is expected to blanket Shanghai in darkness for more than five minutes starting from 9:39 am on July 22 (a Wednesday), although the partial eclipse will last a total of three hours as of 8:23 am.

It is a grand gift for 2009 - coincidentally the International Year of Astronomy - and one that will not present itself for another three centuries. The last time the city saw an eclipse was in 1575.

Zhoushan, a city slightly southeast of Shanghai in Zhejiang province, is expected to be the best place to see the eclipse in the country but anywhere along China's eastern coastline will afford premium viewing due to the trajectory of the sun and moon.

Shanghai is one of 42 Chinese cities that will witness the total eclipse from start to finish, according to the Purple Mountain Observatory of the Chinese Academy of Sciences.

"The entire process will be visible throughout Shanghai except in the northeastern suburbs," said Lin Qing, head of the Shanghai Astronomical Observatory She Shan.

"What makes this one so extraordinary is that it will create the longest stretch of daytime darkness seen in Shanghai (for 800 years, including the past and present)," said Lin. "The total eclipse could last for up to six minutes."

The temperature is expected to drop by 15 to 20 degrees Celsius during those few minutes as the city is plunged into darkness. Local city district governments have been preparing for weeks to prevent accidents and public panic by ensuring street lights are turned on among other measures.

Local companies may need to adopt a more forgiving attitude, however, as some employees plan on taking the day off to marvel at nature's wonders.

"There's no doubt about it," said 24-year-old Chen Ying, a young IT executive. "I'm skipping work on that day." Chen said he plans to head to On Lake (yue hu) on the outskirts of the city to get a pristine natural view unimpeded by skyscrapers or by the fumes emanating from heavy traffic.

"Cameras. Check. Equipment. Check. I'm ready for action and I'm totally hyped about this," he added.

The event is expected to make history as the longest solar eclipse viewed by the largest population ever. Eclipses happen when the moon slides between the Earth and the sun at a specific angle.

Traversing half of the Earth's sphere, the total eclipse will be visible within a narrow corridor. It will begin in India then move over to Nepal, Bangladesh, Bhutan, Myanmar and China.

On the Chinese mainland, it will pass over Chengdu, Chongqing, Wuhan, Hangzhou and Suzhou before hitting Shanghai. The best view is expected to be in the east of the city at Yangshan Deepwater Port one minute after it arrives (8:24 am). People in Beijing, Guangzhou and Hong Kong will only be able to see a partial eclipse.

The eclipse will depart China from Zhoushan before it hits Japan's Ryukyu Islands. From there it will curve southeast through the Pacific Ocean, where the total eclipse will hit its peak at six minutes 39 seconds.

"At the point when the eclipse transforms day into night, four planets will become visible with the aid of the right telescopic equipment, including Mercury, which is normally hard to see." said Yao Jinsheng, a researcher at the Purple Mountain Observatory. The other three planets are Venus, Mars and Saturn.

Few people are as excited about the eclipse as Lin and his team, who have spent their entire careers researching the subject. Having analyzed local weather records over the last two decades, they claim it is "highly probable" the sky will be cloud free on the day.

The eclipse will be broadcast live locally and nationally on Shanghai TV, CCTV and via the Internet.

The curving red lines show the area in which day will be fully transformed into night.

(China Daily 06/06/2009 page13)