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Is a triple rainbow possible?

Is a triple rainbow possible?

Science

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Originally posted by cheshirecatstevens
Try wearing polarized lenses.
Yes, that might help. It depends on the degree of polarization of the rainbow light and the background polarization, it may increase contrast.

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Originally posted by sonhouse
I assume the droplets have to be a certain sized, small window of opportunity, for a rainbow to be visible, so you wouldn't just be near a normal cloud with your hot air balloon. You would have to find the right conditions first. Maybe seeing a rainbow, then launching? Anyone have info on how long a rainbow remains visible from a single spot?
I think a minimum size is required, but beyond that it doesn't matter. You generally don't see a rainbow in clouds, only in rain (or other sprays of water droplets).
In general, if you want to see a rainbow in actual rainfall, you need the sun behind you and the rain in front of you and an unobstructed path from the sun to the rain and back. This is why we normally see rainbows after the rain has passed us and the sky is clearing up - hence the Biblical myth that a rainbow is a promise that the rain is over.

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I have failed to find any references to triple rainbows. It is my understanding that the first and second result from internal reflection, is it possible that triple internal reflection cannot occur? If it did, what angle would the rainbow be at?

I don't think a triple reflection would go towards the observer.

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Originally posted by twhitehead
I have failed to find any references to triple rainbows. It is my understanding that the first and second result from internal reflection, is it possible that triple internal reflection cannot occur? If it did, what angle would the rainbow be at?

I don't think a triple reflection would go towards the observer.
I googled "triple rainbow" and got a lot of results, including pictures.

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According to http://www.jal.cc.il.us/~mikolajsawicki/ex_optics.html, the third and fourth rainbows appear behind you, which means you need to be looking towards the sun, which makes it harder to see. They're also fainter. He reckons that six or more have been observed in lab conditions.

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Originally posted by FabianFnas
I googled "triple rainbow" and got a lot of results, including pictures.
Would you care to reference one with a good picture?

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Originally posted by twhitehead
Would you care to reference one with a good picture?
Take a pick: http://www.google.se/[WORD TOO LONG]

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Originally posted by FabianFnas
[b]Take a pick: http://www.google.se/[WORD TOO LONG]/b]
The first one, is a reflection off the water.
The second, is what is know as a 'supernumerary rainbow'
I cant tell what is causing the third one, but it definitely isn't a third arc.
In the fourth, I can't see a third bow at all.
The fifth shows more 'supernumerary rainbows'

Must I go on?

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Originally posted by twhitehead
The first one, is a reflection off the water.
The second, is what is know as a 'supernumerary rainbow'
I cant tell what is causing the third one, but it definitely isn't a third arc.
In the fourth, I can't see a third bow at all.
The fifth shows more 'supernumerary rainbows'

Must I go on?
"Must I go on?"

If you like. You don't have to.

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Originally posted by FabianFnas
"Must I go on?"

If you like. You don't have to.
So do you agree that triple rainbows are not normally seen in practice and all those photos are of other phenomena? I mean I could photograph a double rainbow and its reflection in two mirrors, but could I claim to have seen a sextuple rainbow?

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Originally posted by twhitehead
So do you agree that triple rainbows are not normally seen in practice and all those photos are of other phenomena? I mean I could photograph a double rainbow and its reflection in two mirrors, but could I claim to have seen a sextuple rainbow?
If you say so. I don't mind.