Halo over Chek Lap Kok
The picture shows a special optical phenomenon called halo, seen over Chek Lap Kok on 17 April 2003. Halos result from the refraction or reflection of light by ice crystals suspended in the atmosphere.
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Halo in the form of ring over Chek Lap Kok on 17 April 2003 (Photo: Courtesy of Mr. C.S. Yuen)