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Analemma 2014, from Hong Kong

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December 28, 2014

View larger. | Analemma and solar terms, 2014, copyright Matthew Chin in Hong Kong. Used with permission. — View larger. | Analemma and solar terms, 2014, from Hong Kong. Copyright Matthew Chin. Used with permission.

The figure-8 shaped curve is called an analemma. It’s a photo of the sun, taken every day at the same time, in this case 7:30 a.m. local time in Hong Kong. Matthew Chin created this analemma in 2014. He also add the Chinese solar terms, which comprise a calendar of 24 periods and climate, set up to govern agriculture in ancient China and referred to in China even now. Matthew wrote:

Due to cloudy or rainy days, the image may be taken before / after the solar term day and are marked +/- nd(ays).

That year’s two equinoxes on March 21 (0° longitude) and September 23 (180° longitude) correspond to the mid-points but not the cross-over point, on the curve.

While summer solstice on June 21 (90° longitude) and winter solstice on December 22 (270° longitude) are located at the top-left and bottom-right on the curve respectively.

The solar term days are listed as below (based on Hong Kong Time) for year 2014 by Hong Kong Observatory.

Click here for solar terms in English from Hong Kong Observatory

Click here for solar terms in Chinese from Hong Kong Observatory

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