Sundog Millionaire
Posted by Graeme Lyons , Sunday, 29 August 2010 13:13
On the way to Pulborough Brooks RSPB reserve to do some moth trapping on the behalf of Sussex Moth Group last night, we saw this amazingly bright sundog. These are formed by hexagonal ice crystals in the atmosphere that refract light at 22 degrees, giving the effect of a bright point of light horizontally to the side/s of the Sun. Often two sundogs appear left and right of the Sun and/or a complete ring all the way around the Sun, but always at a distance of 22 degrees (this must be defined by the shape of the crystals). A complete ring is formed if the crystal are orientated randomly but horizontal refraction occurs when the crystals are vertically orientated, which happens as they start to drift down (this is seen more often than the ring which I have only seen once in Scotland). They look like a patch of rainbow coloured light. Although only one was visible, it was the brightest one I have ever seen and Jo got this great shot from the speeding car on the A27.
Moth trapping was fairly quiet (it must have been for a frequent atmospheric phenomena to usurp a moth tick from the title of a post), good views of the Moon and Jupiter proved quite exciting to visitors whilst the local Sharp-angled Carpet was a tick for me.
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