The terms parhelion, sun dog, and mock sun all refer to the same optical phenomenon: the spot of colour you can see to the left or right of the Sun when its light refracts through hexagonal ice crystals in the atmosphere. Larry Smith (Member 57,002) was admiring the hook-shaped cloud forms known as Cirrus uncinus when he noticed this dazzle of colour among the wisps. The Cirrus uncinus and its resplendent parhelion were accompanied that day by thicker patches of Cirrus, known as Cirrus spissatus, and tiny flattened speckles of Altocumulus clouds.