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On a ‘calm, quiet cloud-watching Sunday’ in Alameda, California, US, Lenore Lustig (Member 45,458) saw a 22-degree halo around the Sun as it shone through Cirrostratus clouds. This optical effect is caused by ice crystals in a thin layer of cloud like this bending, or refracting, the sunlight to form a broad ring with a reddish inner edge and the Sun positioned right at its middle.You may notice the top and bottom of Lenore’s halo appear slightly brighter. This effect is known as a circumscribed halo. It is a more oval ring that appears overlaid on the circular 22-degree halo, and it is the result of sunlight shining in a different way through the cloud’s prism-like crystals. A halo display like this begs to be spotted, but resist the temptation to stare at it, because the Sun shines far too brightly through thin cloud like Lenore’s Cirrostratus to be safe for our eyes. Obscure the Sun with something, or photograph the effect and study that so you can admire the radiance without frying your retinas.