A reader writes:
I love the VFY(Airplane)W feature. Your most recent installment reminds me of a recent article in Scientific American on the science of glories, or circular rainbows, one of which appeared in a photo you posted. The article is beautifully written, tracing the historical significance of glories (they can only be seen against one's shadow and thus may be one reason that holy individuals are seen with halos), all the way to recent breakthroughs in the science behind them. It turns out they are no ordinary rainbows; they depend on a very subtle quantum-mechanical effect known as wave tunneling. The article is behind a paywall at SciAm but well worth a read if you can access it.
(Photo from a Dish reader. More examples on Flickr.)
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