Very rare for some - A circumhorizon arc over Hampshire, Southern England July 17th imaged by Gary Bates.   ©Gary Bates, shown with permission.
"I was watching a hawk flying display at Weyhill Hawk Conservancy when my daughter excitedly came running up to me and told me there was a sun dog in the sky! (although she's only 9 she knows that colours in the sky are not always rainbows and I've told her about sun dogs before!) - Further investigation on the internet revealed it to be a circumhorizon arc, which Richard at confirmed. Richard suggested I send you a copy also as apparently they are quite rare at our latitude.

The image was recorded in RAW format on a 21.1 Megapixel, Canon 5D Mk II. Because the dynamic range was quite compressed and the picture was somewhat more washed out, I have applied "Auto Contrast" to the image to expand the dynamic range. No other processing has occurred on the picture.

Rare indeed at the latitudes of Northern Europe.  The sun must be higher than 58° to form this colourful halo from hexagonal plate crystals drifting in high and cold cirrus. That only happens for a few weeks around the summer solstice in the UK and during that time the southern horizon is often masked by too many cumulus clouds.

Here the sun was just 59° high!


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