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Multiple Simultaneous Rainbows / Supernumerary Rainbows

Ermintruder

The greatest risk is to risk nothing at all...
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Jul 13, 2013
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This took place back in April 2015. I noticed it being Facebooked, but never saw an explanation, until now....the bit about the reversed colours is as remarkable as the reflection effect

http://patch.com/new-york/glencove/quadruple-rainbow-spotted-glen-cove

The photo was convincing to Paul Neiman, who works as a research meteorologist at NOAA’s Earth System Research Observatory. He posted this very helpful explanation on his Facebook page, which he allowed me to republish:

This is an outstanding example of a primary and secondary rainbow (relatively common) occurring together with their reflected-light counterparts (quite rare). Allow me to elaborate.

A typical primary rainbow is caused by refraction and one internal reflection of sunlight within raindrops, resulting in a rainbow that is positioned 41 arc degrees from the anti-solar point (i.e., the point directly opposite the sun – for example, if the sun is 10 degrees above the horizon at your back, the anti-solar point is 10 degrees below the horizon directly in front of you). The refraction causes the separation of white sunlight into its component colors, with red on the outside of the rainbow and violet on the inside.

The secondary rainbow, which is centered 51 arc degrees from the anti-solar point (i.e., the larger of the two bows during a typical display), involves two internal reflections of sunlight within the raindrops rather than one, resulting in a reversal of the color sequence (red on the inside and violet on the outside). We can usually only see the portion of these rainbows above the horizon, because there isn’t a sufficient density of raindrops between the observer and the ground to see the rainbow below the horizon (exceptions include full-circle rainbows viewed from locales such as airplanes and mountain tops).

So far, so good. For the much rarer reflected-light rainbows shown in this spectacular photo, a large glassy-smooth water surface is required behind the observer. This smooth water surface reflects the sun, such that a second solar light source is generated. This reflected sun, which is located the same the number of arc degrees below the horizon as the real sun is above the horizon, creates a second primary and secondary rainbow on the opposite side of the sky from the sun, but with the center of these reflected-light rainbows above the horizon. The geometry dictates that the regular and reflected-light rainbows will join at the horizon, as this photo shows.

Neiman’s explanation requires a body of water to be behind the observer. And, indeed, Oyster Bay – located about 2 miles east-northeast of the train station “likely provided the reflective surface to create the reflected-light rainbows”, he said.
 
I've witnessed this in Falmouth. With the harbour in front and the sea behind, there's often a reflecting surface available whatever the time of day or year.

I've posted about it on this MB somewhere - I'm off for a search to see if it's still here.
 
Here's a recent sighting of a quintuple rainbow in New Jersey (along with explanation and commentary).

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Rare Quintuple Rainbow Captured by Photographer in New Jersey
While shooting a sunset in New Jersey recently, photographer John Entwistle got another gorgeous sight: a sky painted with what looked like a set of five rainbows.

"I could be wrong but that sure looks like a quintuple rainbow at sunset tonight over the Jersey Shore, NJ," Entwistle wrote on Instagram on Sept. 18.

Supernumerary rainbows like this one consist of a primary rainbow — the brightest and most vivid of the bunch — as well as at least two other, less brilliant, rainbows. In the case of the rainbow captured by Entwistle, five supernumerary rainbows were visible. ...

"In general, supernumeraries are quite common. There are many pictures of 2 or 3 supernumeraries," Gunther Können, a retired climate scientist with the Royal Netherlands Meteorological Institute, told Live Science in an email. "But the appearance in nature of 5 supernumeraries is exceptional."

Raymond Lee, a research professor at the U.S. Naval Academy in Annapolis, Maryland, agreed: "Supernumerary rainbows are actually fairly common and, despite their superfluous-sounding name, are an intrinsic part of any rainbow." Even so, seeing these rainbows is challenging because they are not as bright as their primary parent bow and they tend to get obscured by the primary rainbow's vivid colors, he added.

The two types of rainbows form in just about the same way, except for one difference: The main rainbow forms when sunlight enters a water droplet — which is denser than the surrounding air — that light bends or refracts. Once inside the water droplet, the light also reflects off the back of the drop; and then as it exits, it is refracted again. Since different wavelengths of light get bent by different amounts, with this process happening in lots of tiny droplets, you get a rainbow.

The supernumerary bows happen due to interference between light waves that follow slightly different paths inside a raindrop, according to Lee. And these supernumeraries are much more likely to be visible when the raindrops are relatively uniform in size; that's because pairs of light rays that pass through the droplet are more likely to be in phase and create colored light. With different-size droplets, the light waves are more likely to cancel each other out, meaning no light and no supernumeraries.

"Supernumeraries that appear under these conditions are conical, in the sense that their mutual spacing is smaller near the horizon than near the top of the rainbow. This is clearly the case in this picture," Können said.

If you haven't seen one in real life, check out the photo so you know what you're looking for. "Like owning a new car, however, once you're aware of supernumeraries' existence, you start to see them routinely in many different rainbows," Lee noted.

SOURCE: https://www.livescience.com/63724-how-rare-quintuple-rainbow-formed.html
 

Double reflected rainbow photographed in Orkney


A double reflected rainbow has been photographed in Orkney.
The image was captured by Martin Gray at Gyran on Tuesday morning, who described the sight as "amazing".
He said: "I'm used to seeing double rainbows, but this was a really weird-looking thing."
"It was Donna, my partner, who saw the rainbow," he said. "She called me through, but I was on my phone looking at Twitter. When she called me again with real urgency in her voice, I rushed through and there it was - so bright and dominant in the sky.
"I quickly snapped a few photos. It was extremely bright, and odd looking - all odd angles.
"But I didn't even notice the faint fourth arc until I carefully looked at my photographs."
BBC weatherman Simon King said it was an "impressive" photograph.
"It's a really impressive double reflected rainbow," he said.
He said the photographer had a loch behind him at the time.
As a result, sunlight had bounced off the loch before reaching the water droplets from a rain shower in front of him. The sunlight was then bent and reflected inside the droplet back to the photographer.
(C)BBC. '19
 
Bottled Rainbow's
So, there I was stood at my kitchen sink washing up a few dishes, when something right in front of me caught my attention.
A fanfare of spectral colours inside a bubble - inside my washing-up bottle!


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The visual spectral colour are contained within the bubble; somehow each layer is repeated many times over. The colours are lateral and multi-layered right down to the bottom of the bubble. The bubble is slightly distorted as the single 'drip' of liquid slightly alters it's shape (looking from the side).
I found this image intriguing. Why is the light refraction held/shown in multi-layered lateral form? Taking the image to be representative of how a rainbow may be formed, could this mean that rainbow's are contained within an invisible bubble - as rotating the image vertically (i.e. light shining from above) would be an equal image of a rainbow and how it appears to us in the sky - also noting that this is how multiple 'bows' can appear in certain circumstances. Fascinating glimpse into something that may have gone unnoticed though, eh?
 
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This is a phenomenon caused by interference or diffraction rather than by refraction. The different colours inside the bubble interfere with each other and cancel each other out, or amplify each other. To a certain extent this phenomenon occurs on the level of quantum physics, since a single photon is capable of creating interference patterns all by itself.
You are right in that this phenomenon (diffraction/interference) can cause supernumary rainbows in the sky, inside the main bow.

More details here
https://www.sciencefocus.com/science/why-are-soap-bubbles-rainbow-coloured/
Isaac Newton noticed the same thing one day when taking a bath and turned the observation to good use by setting up an experiment where all of the water eventually drained from the top of the bubble. It left a black spot (now called a ‘Newton black film’) consisting of just the two layers of detergent molecules. By following the change in the colours, Newton was able to calculate the size of the detergent molecules – a truly remarkable achievement.
 
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Watch a Newton's Black Film form in this video
Really interesting - thank's for that 'eburacum.' Seems that the effects of gravity on the mass on the thin film of liquid increases the number of visible patterns... to infinity maybe?
 
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Way before the time that I possessed a mobile phone with a camera, but heading home early from my night shift, (it was one of those red sky in the morning, sailor take warning, kind of dawns) and I saw an amazing pink rainbow up against an overwhelmingly orange sky. I’ve never seen the like since then and I’m going back around 30 years or so. I wish i’d woken my wife to get her to witness it too but being a newly wed horny bloke I had different priorities after a rather dull night.
 
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