In his comment to Quick Quiz XXV dragonlife replied with another quiz, an excellent question: what does a rainbow look like when seen from above, for example from an airplane.
I admit that I didn’t know, so I did some research and found this photo taken from an airplane above the clouds.
Maybe you can just see a circular rainbow on the clouds. This is a very unusual sight. I hope this is the right answer dragonlife!
thiNK TWice 
I don’t know too much about color theory but I have researched some holography in my personal time. I actually stumbled upon this blog while looking up prisms in google search.
Very enjoyable blog, very diverse with lots of beautiful scenes.
A friend sent me this today I thought I would share.
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Thanks again Dan.
Really enjoyed the James Burke video. Only he would wear a jacket in the desert!
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It’s a circle in the photo but in real life it would be a dome. Just as you see an aura around streetlights in the fog, it looks like a circle every which-way but in reality is an orb.
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Excellent information Dan, thanks.
I guess it is because of the relative wavelengths of the different colors??
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Thanks for the intriguing question dragonlife, and while I was researching the answer I came across another kind of rainbow which I will soon post.
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Righto!
It is a circle!
See you at the next quiz!
Lol
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