Mountain shadow is sandwiched between the mountain and the Sun

[Metabunker]

In this photo taken by family member mountain shadow seems to be sandwiched between the mountain and the Sun. The Sun was located behind the clouds on the south side of the mountain at around 4 P.M. (38 degree latitude, Atlantic Ocean). See the rays shining up behind the clouds? There's also a small "diamond" at the tip of the mountain, which could be the Sun as well or Sun's reflection. Now if the Sun was located on the right side of the photo (West) the mountain would be lit up, right? Some mimnutes later the shade has disappeared after the clouds dissipated. What could this be and how is it formed?

 

[Ann K]

Taken from inside with the sun below the peak, and the shadow is really on the window itself? Or perhaps the shadow is just on the haze in between the mountain and the viewer? The background is a mixture of clear sky and cloud, and presents no flat surface upon which to cast a shadow, so it isn't behind the mountain.

 

[Metabunker]

Photo was taken from the cobblestone street we stood on. Not from inside of anything. The shadow was cleary behind the mountain. When you look at things live it's much better to see things than in a photo.

 

[JMartJr]

Looks like the clouds are low and the shadow is being cast on the clouds between you and the mountain. If it were further away, wouldn't perspective make it look smaller than the mountain? Instead, it looks larger, suggesting it is in fact closer.

Great pic, by the way. Beautiful.

 

[deirdre]

I was surprised by your text that you think the shadow is behind the mountain, as it looked in front of the mountain to me. but maybe my eye just assumes that since i can clearly see the mountain face is in shade.

these pics look more like the 'behind the mountain' illusion.

 

[Trailspotter]

This is a "volumetric" shadow. A huge bulk of air in the from of the mountain lays in its shadow and scatters less light, than the sunlit air around it. Haze and clouds amplify the effect. Volumetric shadows have been discussed here before, for example, in this thread.

 

[Mendel]

Looks like the clouds are low and the shadow is being cast on the clouds between you and the mountain.

there's an actual cloud (?) in front of the mountain:

Looks like there's a ridge and a valley.

Also, it does look hazy.

 

[Metabunker]

Looks like the clouds are low and the shadow is being cast on the clouds between you and the mountain. If it were further away, wouldn't perspective make it look smaller than the mountain? Instead, it looks larger, suggesting it is in fact closer.

Great pic, by the way. Beautiful.

You can't see that in the photo, but when we were there, live, the shadow was clearly on the other side of the mountain, where the Sun was. There were no clouds on "our" side of the mountain, even that there were clouds on our side in the valley of the mountain. But I guess that's just an illusion, perhaps there were water particles or some kind of metallic particles on our side of the mountain that reflected the shadow onto the south side.

 

[deirdre]

There were no clouds on "our" side of the mountain, even that there were clouds on our side in the valley of the mountain

what?

its like Photoshop "layers". your eye just thinks the shadow is on the back layer because your eye doesnt realize there is a layer between you and the mountain.

 

[Ann K]

This is a "volumetric" shadow. A huge bulk of air in the from of the mountain lays in its shadow and scatters less light, than the sunlit air around it. Haze and clouds amplify the effect. Volumetric shadows have been discussed here before, for example, in this thread.

Isn't this essentially the same kind of atmospheric conditions that make crepuscular rays visible? Without some light scattering off the atmosphere, you'd not see the "rays".

 

[Trailspotter]

Isn't this essentially the same kind of atmospheric conditions that make crepuscular rays visible? Without some light scattering off the atmosphere, you'd not see the "rays".
View attachment 57306

Yes, this is correct. Light "beams" are sunlit volumes, darker ones are volumetric shadows of clouds.

 

[Mendel]

when we were there, live, the shadow was clearly on the other side of the mountain, where the Sun was.

how did you determine that?

 

[Metabunker]

The mountain shadow looked as if it was lying on the clouds across on the other side of the mountain. Is shadow in the sky and a rainbow transparent? Can they both be seen from both sides? Has anyone made such experiment filming the same mountain shadow and/or a rainbow from both sides with two different cameras. Perhaps at the same time an airplane flying through it. Well, when we were taking these photos an airplane was flying through the top of the mountain on the orther side of the mountain and then the airplane suddenly appeared all lit up by the Sun. Unfortunately we did not take a photo with the airplane.

 

[Ann K]

The mountain shadow looked as if it was lying on the clouds across on the other side of the mountain. Is shadow in the sky and a rainbow transparent? Can they both be seen from both sides? Has anyone made such experiment filming the same mountain shadow and/or a rainbow from both sides with two different cameras. Perhaps at the same time an airplane flying through it. Well, when we were taking these photos an airplane was flying through the top of the mountain on the orther side of the mountain and then the airplane suddenly appeared all lit up by the Sun. Unfortunately we did not take a photo with the airplane.

There is no "other side" to a rainbow. The light is refracted through water droplets, and the position in which you see it is determined by the position of the sun so it's visible only to a person whose back is to the sun.

 

[deirdre]

The mountain shadow looked as if it was lying on the clouds across on the other side of the mountain.

but there are only a few white fluffy clouds behind the shadow, most of the shadow is projected onto haze (regardless if you think it is in back of the mountain or in front)

Has anyone made such experiment filming the same mountain shadow and/or a rainbow from both sides with two different cameras.

next time it is foggy out at night have your friend stand in front of car headlights, then run several hundred feet in front of him and several hundred feet behind him and see if you can see the fog shadow from both sides.

*i'm not sure what a hundred feet looks like so you maybe only have to go like 30 feet

 

[Metabunker]

There is no "other side" to a rainbow. The light is refracted through water droplets, and the position in which you see it is determined by the position of the sun so it's visible only to a person whose back is to the sun.View attachment 57313

Thank you, it's a very nice illustration, although I don't understand how a rainbow works, what a refraction is and what does the blue circle stand for? And why is the rainbow bending or breaking at the edges of the blue circle?

 

[Metabunker]

So the mountain (Pico volcano, Azores) would have cast the shadow onto the town below it, but the (invisible to us) atmospheric particles "stopped" or captured the shadow and displayed it as a screen in the sky on the north side of the mountain?

 

[deirdre]

what a refraction is

it's light bending. pretty sure the blue circle is a water droplet, but dont quote me.

what separates white light into a rainbow (like prisms -or certain water droplets-do):

Article:

A prism is a triangular piece of glass or plastic. To get it to produce a mini-rainbow, you allow a narrow strip of white light to fall on one face of the triangle, like this:

(See this page for a neat java applet that demonstrates the dispersion of a prism.)

The dispersion of colors in a prism occurs because of something called the refractive index of the glass. Every material has a different refractive index. When light enters a material (for example, when light traveling through the air enters the glass of a prism), the difference in the refractive index of air and glass causes the light to bend. The angle of bending is different for different [colors] wavelengths of light. As the white light moves through the two faces of the prism, the different colors bend different amounts and in doing so spread out into a rainbow.

Source: https://science.howstuffworks.com/nature/climate-weather/atmospheric/question41.htm

 

[Ann K]

Thank you, it's a very nice illustration, although I don't understand how a rainbow works, what a refraction is and what does the blue circle stand for? And why is the rainbow bending or breaking at the edges of the blue circle?

Yes, it's a water droplet. Sorry I didn't explain more fully. That's why you see rainbows after a rain, when the clouds have moved on far enough that the sunlight can shine in, but there are still droplets in the atmosphere.

See the illustration from @deirdre's post of the straw looking like it bends when it enters the water. But sunlight is made up of all the colors of the visible spectrum, and different colors (which have different wavelengths) each bend a different amount. So a prism or a raindrop splits that sunlight to spread the different colors apart from each other so you can see each color separately.

 

[Mendel]

Thank you, it's a very nice illustration, although I don't understand how a rainbow works, what a refraction is and what does the blue circle stand for? And why is the rainbow bending or breaking at the edges of the blue circle?

In very simple terms, a rainbow is a big circle (really 2 circles, but the second one is faint) around the shadow of your head, where sunlight strikes water drops/droplets in the air. On a sunny day, you can see them on a fountain or make one with a garden hose. You usually only see the full circle from an airplane, because normally the lower part of the circle would be underground, that's why we see a bow and not a full circle.

The shadow can be seen from anywhere, and photographed from anywhere, because it actually exists in 3-dimensional space. Its visibility obviously depends on the background. With an accurate date and time, we could find the aircraft track and confirm that it traversed the shadow volume.

The fact that the cloud behind the shadows looks darker than the cloud with bright haze in front does not mean there's shadow on the cloud; with a real shadow, the cloud should look rain cloud dark. It's an optical illusion.

 

[binarysoftware]

The phenomenon you're observing in the photo is called a "mountain shadow." It occurs when the Sun is located behind a mountain, casting a shadow of the mountain onto the atmosphere. In this case, with the Sun behind the clouds on the south side of the mountain, you see the shadow of the mountain appearing to be sandwiched between the mountain itself and the Sun. The rays shining up behind the clouds are likely crepuscular rays, which are sunlight streaming through gaps in the clouds.

The small "diamond" at the tip of the mountain could indeed be the Sun itself or its reflection, as you suggested.

If the Sun were on the right side of the photo (West), the mountain would indeed be lit up, and the shadow would be cast in the opposite direction. The change in lighting you observed after the clouds dissipated is due to the movement of the clouds allowing the direct sunlight to reach the mountain.

In summary, the photo captures a mountain shadow formed when the Sun is obstructed by the mountain, with crepuscular rays and the possibility of the Sun or its reflection appearing as a "diamond" at the mountain's tip. The shadow disappears as the clouds clear and direct sunlight reaches the mountain.

 

[Mendel]

Some mimnutes later the shade has disappeared after the clouds dissipated. What could this be and how is it formed?

Actually, the brightness had disappeared, when the clouds/haze/water vapor that caused the atmosphere to be bright had dissipated.

The shade was always the same color as the cloudless sky. It simply wasn't bright because the sunshine didn't reach there—the mountain was in the way.