Measuring a sun dog in Silloth

 I saw this sun dog in Silloth last week. It is the small streak of coloured light above the red dot (I think the red dot will be lens flare) and just by the roof of the house. It appears in real life as a slight rainbow. I wasn't sure this time - it seemed so far from the Sun. Perhaps it was because the Sun was so low. The Moon always seems bigger lower down but it just an optical illusion. So I decided to measure it. It took one hand splayed thumb to little finger and 3 fingers of my other hand held at arm's length. I came home and measured.

Imagine a right angled triangle going out from my eye to my little finger, across to my left hand finger and back to my eye. My fingers were 70cm in front of my eye. Let's call that the hypotenuse. Sin theta = 24cm/70cm. So the angle = 20 degrees. It is 22 degrees for a sun dog due to the optical geometry of light in water crystals high in the atmosphere. So it was a sun dog!