UKC

Hi all,

I saw some interesting light phenomena out up around Braeriach / Moine Mhor today, including some fogbows. However, this one has me stumped. I’ve done some sleuthing around the internet and still can’t work out what I’ve seen here. The halo at ground level was sat on the horizon for about half an hour, directly under the sun. It was visible with the naked eye, though very bright. It was sub zero and a mixture of fog and light snow flurries up there. Anyone got any ideas what this is or what’s going on here?

Possibly a light pillar

Cheers Dan. Aye I wondered about that. The images I’ve seen of those seem to have a more distinct pillar though, whereas this was very much a clear separate ring on the horizon. That image you’ve posted doesn’t look a million miles away though.  

It looks like the tip of a lower tangent arc, with the rest of the arc hidden below the horizon. The sun looks to be about the right elevation for it.

https://atoptics.co.uk/blog/perfect-lower-tangent-arc-opod/

Have a look here and search for "lower tangent arc" for more photos -

https://cloudappreciationsociety.org/

sun dog?

I saw a full circle one in japan just before a typhoon last year.

Looks like a halo (same as generates sundogs etc) being caused by ice crystal blowing about in the low cloud.

That’s spot on I think - hadn’t come across that at all but those images certainly seem to match. Fascinating, thanks.

Your photo is not a sundog but is a circumzenithal arc. 

Nah, storm petrel is right - lower tangent arc.

Circumzenithal arcs only appear near the zenith, i.e. well above the sun in this photo.

Was talking about the other photo. 

Although I agree with you and Storm petrel about the first one. 

My bad, sorry Dan!