HartRAO Home > news > Two Suns in the sky 2000/12/09

What is going on?

The high cirrus clouds contain ice crystals. These refract sunlight and produce coloured luminous spots 22 degrees on either side of the Sun. The real Sun is behind the telescope, as can be seen from the shadows on the ground.

The "Sun" on the right is refracted light from the ice crystals. It is called a "sundog" or "mock Sun" or "parhelion" (meaning "beside the Sun", in Greek.)

The photograph was taken by staff member Louis Barendse during the public visit to HartRAO on Saturday 9 December 2000. Click on the photo for a larger view.