Looks like another myth bites the dust

[Sticks]

Looks like there is no crock of gold at the end of the rainbow :(

Link (http://www.dailymail.co.uk/news/article-1143482/Found-The-end-rainbow--theres-pot-gold.html)

[NEOWatcher]

Looks like there is no crock of gold at the end of the rainbow :(
I see a crock in the story though.

It's good they explain what a rainbow is, but it's a crock that they re-inforce the idea that the end is in a particular place when it is merely an illusion. I wonder if his estimate of it's speed could be correlated with the reading on his speedometer? :doh:

Good image of a faint double rainbow in the second one.

[HenrikOlsen]

I see a crock in the story though.

It's good they explain what a rainbow is, but it's a crock that they re-inforce the idea that the end is in a particular place when it is merely an illusion.
I wouldn't call it just an illusion, I'd rather call it just a direction.

[Nicolas]

I was just going to say, if two persons watch the "same" rainbow from a significantly different position, wouldn't they see the end of the rainbow in a different location as well?

Never mind looking at it from a plane, then there's no end at all. Booooo no gold!

[Sticks]

tricky things those leprechauns :)

[ABR.]

I thought this is what was at the end of the rainbow.

[NEOWatcher]

I wouldn't call it just an illusion, I'd rather call it just a direction.
Yep; word pulled out of my...er...hat. Anything to convey that it isn't really where it appears to be.

[KaiYeves]

What's the "dusr"?

[Sticks]

What's the "dusr"?

:doh:

I have corrected the typo - and well done for spotting it

[BigDon]

Well good thing there is the ol' standby, "hit a dwarf on the head with a stick and he'll turn into a pile of gold."

[PetersCreek]

I saw the "end" of a rainbow once, in a picturesque field not far from my flat in Germany. Alas, no gold was in evidence there, either.

[LotusExcelle]

I have a vivid, almost uber-real memory of a double-rainbow. I've never seen one in real life since. A really impressive sight.

[Nicolas]

I've seen them quite a few times. The fact that it tends to rain here might help. :)

[RalofTyr]

It's quite obvious the gold's underground.

In New Jersey, if you dig at the end of a rainbow, you won't find gold, just something you'd have to call CSI to investigate.

[PetersCreek]

Double rainbows are quite common in my area, as well.

[DyerWolf]

I saw the end of the rainbow once while driving through Camp Pendleton. Since Marines never get lucky with money, we decide the pot o'gold was at the other end...


Of course, I've always liked this pot at the end of the rainbow (http://www.geocities.com/perry_peterson_1999/pot3.jpg)

[Krel]

I saw the end of the rainbow once while driving through Camp Pendleton. Since Marines never get lucky with money, we decide the pot o'gold was at the other end...


Of course, I've always liked this pot at the end of the rainbow (http://www.geocities.com/perry_peterson_1999/pot3.jpg)

You hit the nail, square on the head. It is obvious that they are all looking at the beginning, and not the end of the rainbow. If you just follow it to the other end, the end of the rainbow, not the beginning, then that is where you will find the gold! :dance:

David.

[crosscountry]

well, it's not even physically possible that photo. Rainbow physics isn't that complicated, and I think that photo is doctored.

[Robinson]

He even managed to estimate how fast the rainbow was travelling as it moved northwards.

Speaking from his U.S. home, he said: 'Rainbows seemed very dynamic in movement when you are near their base.

'The speed of movement across the ground was about 20 to 30mph as the base of the rainbow moved with the storm. It lasted for about five minutes.'

http://www.dailymail.co.uk/news/article-1143482/Found-The-end-rainbow--theres-pot-gold.html

This sort of "reporting" might seem like some harmless fun, but the bad science, or rather, the absence of science is appalling.

No really, it is awful. The rainbow in the picture, just like the one you see when you see one, is inside your head, or inside the camera. It is a creation of the observer, it doesn't exist "out there" on the road, in the sky, anywhere except in the mind, or the photographic sensor.

Like all rainbows of this sort, it is actually a complete circle, with the sensor/observer in the exact middle. And, it moves exactly with the observer, a fact anyone can demonstrate for themselves, by moving your head while looking at "a rainbow". There is actually a separate rainbow for each eye, so closing and opening one eye at a time will also demonstrate this fact.

At noon, you can use a hose outside in the sunlight, and observe that you are in the middle, the rainbow will be a circle around you, which will "move" exactly as you do, always appearing in the exact same place, around your eye. Each person sees their own rainbow, around them, and it moves with them.

The driver of the car in the story, and it appears the author as well, don't seem to know this. The reporting of a rainbow moving due to the storm is untrue.

As is the idea there is an end to a rainbow. It is a circle, the only end is where the water stops refracting and reflecting light.

[SeanF]

http://www.dailymail.co.uk/news/article-1143482/Found-The-end-rainbow--theres-pot-gold.html

This sort of "reporting" might seem like some harmless fun, but the bad science, or rather, the absence of science is appalling.

No really, it is awful. The rainbow in the picture, just like the one you see when you see one, is inside your head, or inside the camera. It is a creation of the observer, it doesn't exist "out there" on the road, in the sky, anywhere except in the mind, or the photographic sensor.
You're stretching it a bit here, aren't you? The rainbow is a result of light refracting in a water droplet. Both the water and the light are "out there" when this occurs, so why is the rainbow not "out there" as well?

Plus, a rainbow can be reflected off a lake or a mirror, so mustn't the rainbow exist in the light before it reaches my eye?

It seems to me that there a more correct explanation would be that there are an infinite number of rainbows that exist "out there," but my eye only sees one at a time. :)

Crosscountry, can you elaborate a bit on why exactly that specific photo is "impossible"?

[Robinson]

If anyone actually does a scientific experiment, with a "rainbow source", like a waterfall, a hose, or other close source of water droplets, the sun, and your head, you can simply see how the "rainbow" moves exactly with your head, or more accurately, your eyes.

Yes, there is probably an infinite amount of light, but the finite act of sensing the circular rainbow occurs in exactly the point of reception, be it camera or eye.

To take this further, if somebody is exactly behind you, they see a rainbow as well, around them, but the location differs. As does your own rainbow, moving away or towards the water source changes the apparent size, yet measuring the circle, it never changes, it is always the same size. The angle is always the same.

This can be experienced as well with a scientific observation. So the little rainbow in the fountain, and the giant one spanning the horizon, are both the same size. Because they only exist to the observer.

Driving along with rain off to the side, and the sun behind you, (it always will be behind you, with a regular rainbow), the "rainbow" will move exactly as fast as you drive.

[Robinson]

But don't take my word for it, get out there and do the experiment! 4 teh science!

[HenrikOlsen]

Crosscountry, can you elaborate a bit on why exactly that specific photo is "impossible"?
I'll take a stab at that.
Basically the problem is that it doesn't look like there's rain between the camera and the portapotty, which there'd have to be for a rainbow to show.

[HenrikOlsen]

You're stretching it a bit here, aren't you? The rainbow is a result of light refracting in a water droplet. Both the water and the light are "out there" when this occurs, so why is the rainbow not "out there" as well?
Its apparent solidness/existence as a single "object" is an illusion cause by reflections in many drops, it's a construct of lots of many-colored flashes of light which happen in a nice pattern.

[SeanF]

I'll take a stab at that.
Basically the problem is that it doesn't look like there's rain between the camera and the portapotty, which there'd have to be for a rainbow to show.
Oh, I thought CC was referring to the photo in the OP.

Its apparent solidness/existence as a single "object" is an illusion cause by reflections in many drops, it's a construct of lots of many-colored flashes of light which happen in a nice pattern.
That's why I said he was "stretching it." Nobody thinks the rainbow is a solid object - it's a pattern of light, but patterns of light still have an objective, physical reality.

Refracting light through a prism to view the spectrum is essentially the same thing, isn't it? Would we say that only exists in your eyes/brain?

[Robinson]

Not the same. You can project the spectrum onto something, in fact, you have to, to be able see it. (if you look at the prism you can only see one color at a time, I've done it)

A rainbow can't be projected, in the sense there isn't anything there to project, the circle is created by the observer.

A spectrum doesn't move when you do, nor does everyone see it differently.

Oh sure, you can argue that everything is subjective, but that is just avoiding the point.

[Robinson]

This really is one of those cool science things you can observe for yourself. You just need sunshine and a hose.

[mugaliens]

You know what this means?

Those sneaky leprechauns are tunneling!

[Sticks]

Is that Quantum tunnelling?

[Sam5]

But don't take my word for it, get out there and do the experiment! 4 teh science!

Surely someone has written a paper about this by now.

Where I live, I sometimes drive on a road high up on a cliff. Sometimes it rains, and when I see a rainbow while the road cuts through a hill (with banks on each side of the road), I see the two ends of the rainbow stopping on both hill banks (one on the left and one on the right), so the rainbow (I figure) comes from raindrops that are within a hundred or so yards of my car.

Ok, now I drive on and suddenly the bank on the right is gone, and down below on the right is the cliff and a valley about a half-mile away, and the right end of the rainbow seems to go down into the valley. So I'm still trying to figure out how far away from me the drops of water are that produce the rainbow. When I see the bow "end" in the valley a half mile away, am I still seeing the bow that is produced by drops that are less than 100 yards from my eyes? I think so, but I'm not sure.

[Robinson]

You see the rainbow from any and all drops that are closest to the eyes. The rain might be 20 feet in front of you, but the rainbow will be seen as over anything in the field of vision.

This isn't obvious until you experience it. Half the rainbow can be from a spray of water right in front of you, and the other half rain miles away, the rainbow will still be a perfect circle, around your eye(s). (Remember, there is actually one around each eye).

The advantage of using a hose or waterfall or a source close by, is that when you move, it is very obvious the rainbow moves with you. When the rain is far away, it isn't easy to see the movement, relative to the source of the light.

But experimenting will show it is all the same rainbow, and it is yours. Rainbows are one of those special "things", that the farther away the seem, the larger they get.

Checking Wikipedia, this doesn't appear to be a great mystery.

A rainbow does not actually exist at a particular location in the sky. Its apparent position depends on the observer's location and the position of the sun.

Lots of sources on WP. Plenty of papers on the rainbow.

[SeanF]

This really is one of those cool science things you can observe for yourself. You just need sunshine and a hose.

I'm not getting my point across. :)

I'm not disagreeing with you on the, shall we say, visual effects of a rainbow, Robinson. I'm just quibbling with your description of the cause of them.

[Robinson]

The cause?

[SeanF]

The cause?
For lack of a better word, yes. :)

The whole "it's all in your head" bit just rubbed me the wrong way. I see you're point, I just think you took it too far. ::shrug::

[Robinson]

Well, the water and light aren't inside your head.


No wait, the light actually is when you see it.

[Krel]

Wait, so y'all are telling me that the Skittles commercial is lying to me? :cry:

David.

[crosscountry]

You're stretching it a bit here, aren't you? The rainbow is a result of light refracting in a water droplet. Both the water and the light are "out there" when this occurs, so why is the rainbow not "out there" as well?

Plus, a rainbow can be reflected off a lake or a mirror, so mustn't the rainbow exist in the light before it reaches my eye?

It seems to me that there a more correct explanation would be that there are an infinite number of rainbows that exist "out there," but my eye only sees one at a time. :)

Crosscountry, can you elaborate a bit on why exactly that specific photo is "impossible"?



physics says that the rainbow end will never be directly in front of you.
http://www.batesville.k12.in.us/Physics/PhyNet/Optics/Refraction/Rainbows_2.html
http://eo.ucar.edu/rainbows/

lots of things contribute to this conclusion. First, the rainbow will always be opposite the sun. Reflections from the car put the sun behind and slightly to the left. That would make the center of a circle just out of the picture on the right. But this thing is most certainly centered far to the right.

But most importantly, the angle of the rainbow is entirely wrong. If you had the sun behind your head the rainbow would be 42 degrees from your front or 138 from directly behind you. The end of the rainbow will never be in front of you with the sun behind.

Now, find where you think the sun is in this scene and extract where the center of the rainbow would be (directly opposite the sun). Does that fit? Working from that you can see that the end wouldn't be where it is.


To continue, look at the car in front. See where the shadow is on the left side? It is between the wheels but the shadow on the right side slants. Do they match?

Also, he says the rainbow lasted about 5 minutes and traveled between 20 and 30 miles per hour. That puts him traveling 20-30 miles an hour or he would have outrun it. Of course you cannot outrun a rainbow.

And lastly, in the second picture the sun angle isn't right again. Look at the reflection of the sun on the metal barrier. That puts the sun behind and slightly to the left, and again the center of the rainbow isn't opposite that like it must be to follow the laws of physics.


Or maybe I'm seeing things entirely wrong.:sick:

[Sticks]

I could muddy the waters and ask if the way a rainbow happens is similar to chromatic aberration, i.e do all the little raindrops constitute one large lens?

:think:

[Robinson]

I could muddy the waters and ask if the way a rainbow happens is similar to chromatic aberration, i.e do all the little raindrops constitute one large lens?

No, but that could bring an interesting turn to the discussion. But first, I must address the post above yours, in which the photo is discussed.

[Robinson]

Reflections from the car put the sun behind and slightly to the left. That would make the center of a circle just out of the picture on the right.


Not correct. The shadows are the real key, but even with no shadow as reference, you can draw lines from the circle (rainbow) to show the center point, which in this case, and all cases, would be where the shadow of the observer, or camera, is located.

In other words, if the rainbow is a circle, and you can see your own shadow while looking at it, your head will be exactly in the middle of the rainbow.

In this photo, the camera is only showing part of the circle, not unusual, as a wide lens is required to show anything more. If you looked at the wiki article you will know why. The "center", or more correctly, the shadow of the camera, actually is off to the right, looking at the shadow in the photo, you can figure out exactly where it would be. Rough estimate, about 10 feet to the right, far outside the cars interior.

What we are seeing is unusual, in that the spray from the cars on the wet road causes the source of water to end, right in front of the photographer. Notice his windshield is dry. So is the SUV to the left, you can see the sun shining on it, and it's shadow,

I mentioned it doesn't matter if part of the rainbows source of water is far away, and part is close. In the first photo the source of the higher rainbow is the rain up ahead, the lower portion is from spray from the roadway.

You can't tell any difference, especially in the photo. This is why it "ends", there is little or no spray on the road between the SUV and the car in front, kicking up water from the road. No doctoring required. It is a real photo.

I could draw diagrams and explain at length, but what would be the fun in that?



Or maybe I'm seeing things entirely wrong.:sick:

I have observed and photographed rainbows for many years, and it isn't easy figuring these things out. Direct observation, as I keep suggesting, will show far more than I can explain here.

For example, with a garden hose, and waiting for the right time, you could recreate the lighting in that photo, and see exactly where the center of the rainbow would be, how the physics of it all works. OK it would help if somebody else sprayed the hose, and you worked the camera.

But an afternoon, (late afternoon is best) with a water source and the sun, will learn you all kinds of cool stuff about light and water droplets, and your own eyes.

[SeanF]

Well, the water and light aren't inside your head.

No wait, the light actually is when you see it.
Well, yes, but the light from anything you see is inside your head when you see it. Doesn't mean it only exists inside your head.

When you look at a rainbow, the specific image you see with your right eye is only visible from the point where your right eye is. So, yes, if you move your right eye, you will no longer see that specific image. But to say that if you move your right eye, that specific image no longer exists is, as I said, stretching it. :)

And I agree with you about the photo. CC, as for the front car's shadow, it looks to me like it's angled because the road surface drops down there on the shoulder. At any rate, I've read enough discussions on the "moon hoax" to know you can't accurately determine the sun's location from shadows on the ground. :)

As for the glare on the SUV, sure it's slightly to the left-of-center of the SUV, but the SUV is not aligned with the camera's line-of-sight. That back surface is sitting at an angle. It's similar with the glare on the road guard to the right. That's a curved surface there, and the glare is pretty much always going to appear pretty close to the center of the curve.

[Robinson]

Well, yes, but the light from anything you see is inside your head when you see it. Doesn't mean it only exists inside your head.


I know, that is why I mentioned you could say everything is inside your head (vision wise), but that avoids the point.

[mugaliens]

I'm getting a headache - not ... enough ... room ... left ... for ... all ... this ... water ... and ... light.... aarrgghhh!

[crosscountry]

I've been watching rainbows for a long time and took the time to learn about them.