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Strange Glow in the Daytime Sky

-- | May 21, 2013

Question: Today, while I was walking down my street, I noticed a strange thing in the sky. One part of the sky was illuminated in a good shade of Blue. Unlike the blue sky, it was more radiating and glowing. Like that caused by ions. I was wondering what could be the reason for this phenomena? I stood there observing for a while and saw clouds passing through that patch. That patch changed shapes too, not very apparent but with time one could notice it wasn’t the same as before. I also tried to capture it using a very poor quality phone camera, as I didn’t have a good one then. I can send the pictures across to you. Hope you can help. I’m just very curious. Is there a possibility it could be due to the solar storm that occurred two days ago? Please help. — Aarthi

Answer: It is always difficult to identify various atmospheric phenomena as there is quite a variety. Your description might match that of a “sun dog”. The Wikipedia page on sun dogs has a nice description. Their scientific name is “parhelion”, as they are bright patches which can appear 22 degrees distant on either side of the Sun. These patches of light are caused by refraction off of ice crystals in the Earth’s atmosphere. I think that this is probably the best explanation for what you saw in the sky.

Jeff Mangum

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