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Shadow in rainbow hallow of A330

Posted: Sun Jan 06, 2019 3:33 pm
by TutiFruiti
Hello All.
I want to understand the physics and meterology aspect behind the phenomenon. It shows an A330 landing at IST and when it descend into cloud cover it shows the airplane shadow, which is normal, but the important part is the shadow is surrounded by a rainbow shaped hallow. For first 10 seconds of video it is clear.


https://youtu.be/KxlQhi83PdA

Thankyou

Re: Shadow in rainbow hallow of A330

Posted: Sun Jan 06, 2019 4:10 pm
by alesfr
It's very common, I've seen it many times as pax, sometimes you can observe it for quite long periods of time when the aircraft flies not very high above the clouds

Wikipedia link below

https://en.wikipedia.org/wiki/Brocken_spectre

Re: Shadow in rainbow hallow of A330

Posted: Sun Jan 06, 2019 4:55 pm
by TutiFruiti
Thanks.. perfect answer.. got it

Re: Shadow in rainbow hallow of A330

Posted: Mon Jan 07, 2019 12:06 pm
by SAAFNAV
Also known as the guardian angel to flight crew

Re: Shadow in rainbow hallow of A330

Posted: Mon Jan 07, 2019 3:42 pm
by 747Whale
The halo appearance is simply an effect of refraction; you could think of it as "bending" light. You can see some effects of refraction if you hold your hand against a bright light or bright sky; the fingers sometimes appear thinner than they are, and if you look at the the spaces between your fingers, you may see what look like lines paralleling your fingers; lines which aren't really there. This is refracted, or "bent" light, and can appear to concentrate around the shadow of an object if at the right focal length.

As others noted, it's quite common to see in the cloud and sometimes against the ground. It makes a pretty picture when flying directly into a cloud with the sun behind, sometimes seen in the cockpit and really hard to catch just at the right time to photograph.

Re: Shadow in rainbow hallow of A330

Posted: Tue Jan 08, 2019 11:49 am
by TutiFruiti
747Whale wrote:
The halo appearance is simply an effect of refraction; you could think of it as "bending" light. You can see some effects of refraction if you hold your hand against a bright light or bright sky; the fingers sometimes appear thinner than they are, and if you look at the the spaces between your fingers, you may see what look like lines paralleling your fingers; lines which aren't really there. This is refracted, or "bent" light, and can appear to concentrate around the shadow of an object if at the right focal length.

As others noted, it's quite common to see in the cloud and sometimes against the ground. It makes a pretty picture when flying directly into a cloud with the sun behind, sometimes seen in the cockpit and really hard to catch just at the right time to photograph.


Thats perfect explanation. To me it seems that phenomenon of diffraction as we studied in college back then. Diffration is refraction at edges . Yes. the window to capture this phenomenon will be short as it appears at entrance to clould cover and also depends on orientation with respect to sun..