Dogs of the sun: Uncovering the mystery of parhelion

Sun dogs, also known as parhelia, are an optical atmospheric phenomenon where bright spots of light appear on either side of the Sun, often forming a halo.

What causes sun dogs?

• Caused by the refraction of sunlight through hexagonal ice crystals in cirrus or cirrostratus clouds high in the atmosphere.
• Usually appear when the Sun is low on the horizon.
• They often form at 22 degrees to the left and right of the Sun.

Where & when seen?

• Most visible in cold regions or during winter, but can occur anywhere if conditions are right.
• Common in polar and mid-latitude regions.

Relevance for UPSC (Prelims + Mains)

Sample UPSC Prelims MCQ

1. The phenomenon of “Sun Dogs” is associated with:
2. Volcanic eruptions
3. Ice crystal refraction in the atmosphere
4. Magnetic storms in the ionosphere
5. Solar flares from the Sun

Answer: B) Ice crystal refraction in the atmosphere