Getting Close To Rainbows

_Danforth_

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#1
I do a lot of driving for work - recently, a lot of this driving has been in Scotland. The weather up here has been an exciting mix of low-angled sunshine and driving rain; as you might expect, this means lots and lots of rainbows, hovering over the very pretty landscape.

My wife once told me she has a very clear memory of driving *right through* the coloured beams of a rainbow, with the inside of the car going yellowy-green because that's the colour the car passed through. We talked about it, and how optics says it's impossible, but it's a clear adult memory for her, and she concluded it must have been a different optical illusion from normal.

While that didn't happen to me, I did come a lot closer to a rainbow than I thought was possible under science.

Driving around the Trossachs about a month ago, through some rocky terrain, quite high up. Rainbow ahead of me, coming down on my right. Came round a bend in the road at about 35mph and - there was the end of the rainbow. It stopped on my side of the road, at what looked like no more than three or four car lengths ahead. As near as I could tell, the "end" didn't move as I approached it, but the colour intensity rapidly lessened - vanishing from my sight a split-second before I reached it.

It made me wonder about the legend of fairy gold at the end of a rainbow - a myth that makes more sense, if you can get that close! In my sheltered townie upbringing they'd only ever been in the distance.

How close can you get to a "classical optics" rainbow?

Or did I see something else entirely, a different effect, maybe through the rain spray hovering over the road? You get prism patterns watering the garden sometimes.

Is this also what happened to my wife?

Or can we all reach the end of rainbows and it's been hushed up by Big Weather? :-D
 

EnolaGaia

I knew the job was dangerous when I took it ...
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#3
All classic rainbows are prismatic phenomena, but it's not the case that all prismatic phenomena are classic rainbows.

Classic rainbows are halo segments or half-halos seen at some distance relative to the observer. You have to be at some distance to see the halo (or segment thereof), and this is why a true rainbow's end is impossible to reach.

Given substantial water vapor in the air and strong light sources it's possible to see indistinct rainbow-style prismatic effects all around you. A good example would be rainbow-colored blobs or patches visible in the spray kicked up by cars on an expressway. I've seen 'rainbow' colors all around me in light morning fog or mist.
 

_Danforth_

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#4

Lord Lucan

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#5
I wasn't quite as close as other pics in threads here when I snapped this image in Singapore earlier this year ( I was also 32 floors up) but you can just make out the rainbow ending as it hit the water of Marina Bay.
An enormous thunderstorm had just passed by and 10 minutes earlier you couldn't even see the water through the rain and cloud.
rainbowsingapore.jpg
 

damando5

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#6
My sister told a story once about coming back from a vacation that her bf and herself saw the end of the rainbow and pulled off of the hwy and ran into a field just to experience what would happen. [Not sure if they thought a leprechaun was going to give them something] However I would had love to know what the other motorists thought was going on.
 
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