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The Colors In The Rainbow Are Backward???

Today Tony Fairchild sent us this picture on facebook. What you will see is an incredible shot of a double rainbow, but something seems odd...




This picture shows an odd characteristic of the secondary bow above the first rainbow... the colors are backward! Here is a good explanation I have from a blog I wrote last year...


Why are the colors reversed in a secondary bow???


Last year, we had some great photos taken of double rainbows in our area. I have attached a few images from a co-worker Steve Nally. I will tell you there is something very different between the primary rainbow closer to the ground and the secondary bow which is higher up. Can anyone figure out the difference???


Double bow 1 


Double bow 2 


More pictures from Kathy Robinson...


Rainbow 003 











Answer Below


The pictures above show what we refer to as a double bow. That is two rainbows that share the sky and shape, but the secondary bow is always further away from the ground. To understand how a double bow works, you have to first understand how the primary bow is formed. We get rainbows when sunlight shines directly into a rain drop, then bounces off the back of the raindrop, and is reflected to your eyes. The water acts like a prism and spreads the light into the full spectrum of colors. When a secondary bow is formed, the light has to bounce twice off the back of the rain drop before it is reflected to your eyes. That means more light is muted by the rain drop (the cause of it being less bright) and like a mirror the colors are flipped backward to the primary rainbow since the light bounces off one more surface of the raindrop. So everytime the light bounces off the back of the drop, the reflection, much like a mirror, is flipped and reversed. This is same thing as when you look in a mirror everything looks backward. Here is a good illustration I drew up. Sorry if it is a bit crude. :)


Double Bow 




If you ever have any questions, please remember I can be reached on facebook easily! Just follow the link below to my facebook page and click "LIKE"!




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awesome explanation, thanks!!!

Nothing is wrong with the photo then?
You said on FB that there was something wrong -_-

Actually, a rainbow is a full circle - like a shiny dinner plate with a very shiny rim. The center of the circle is where the shadow of your head is.

The bands aren't made the same way a prism separaes light. The red circle about 42 degrees wide, and violet is only about about 40, so the shiny rims are at seen at different places. Inside the colored bands, all the colors re-combine to make white. This is visible in most of your photos as a bright region of the sky.

In the secondary, the second reflection does NOT reverse the colors. The circles are centered on the sun itself, not your shadow, and are so large (127 degrees for violet and 130 for red) that they wrap around the top of the sky. Red is still on the "outside," but "outside" is now "down."

Beautiful images,thank you for sharing the article.

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