Light rays on 'wrong' horizon

[bejay1957]

Not sure if anyone else in the Thames Valley was out watching the sunset this evening, or more precisely away from the sunset - I was watching from 1940-2010BST; at first I thought it was an optical illusion but I did capture this in some images on the camera.

On the horizon directly opposite where the sun was setting, a wide diffuse 'fan' of rays of light was clearly discernible, over the course of 10-15 mins this broadened as it swung 'up' and Northwards, and then narrowed again as was eventually angled about the same to the North as it had been to the South when I first noticed it; at times shadows were visible within this fan of diffuse light - all in all it looked like crepuscular rays on the wrong horizon.  This light had disappeared after the sunset, so fairly sure it was an optical phenomena in the high fine cloud and/or dust.

(images have been tweaked slightly to try and enhance the fan of light)

 

EDIT: Should have googled first, they are anti-crepuscular rays - first time I've really noticed them

[acey]

Yes, it's a perspective effect, like the way the rails of a train track or overhead wires seem to converge at a distance in either direction. We tend not to appreciate that sunbeams in the sky are actually parallel, like the tracks or wires: this effect helps bring it home. Always worth looking out for if you have a clear horizon opposite the sun. I've mostly seen it over the sea but that might just be an accident of geography.

[AlentejoSkies]

I saw this once too and it was a stunning effect. I often look for it but so far it's only that one time - out there in Thailand that night I almost got married...

The same perspective effect is often visible, but nowhere near as amazing, on aircraft contrails if several aircraft are flying from one horizon to the other.

[Pete Presland]

Fascinating! Thank you for sharing some else to look out for.