Astronomy Picture of the Day - Lunar Halo over Snowy Trees

APOD.NASA.gov ^ | 1 Feb, 2021 | Image Credit & Copyright: Göran Strand

[MtnClimber]

Explanation: Have you ever seen a halo around the Moon? This fairly common sight occurs when high thin clouds containing millions of tiny ice crystals cover much of the sky. Each ice crystal acts like a miniature lens. Because most of the crystals have a similar elongated hexagonal shape, light entering one crystal face and exiting through the opposing face refracts 22 degrees, which corresponds to the radius of the Moon Halo. A similar Sun Halo may be visible during the day. Exactly how ice-crystals form in clouds remains a topic of research. In the featured image taken last week from Östersund, Sweden, a complete lunar halo was captured over snowy trees and rabbit tracks.

[MtnClimber]

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[MtnClimber]

[MtnClimber]

Pinging the APOD list.

🪐 🌟 🌌

[mylife]

I saw this with the wolf moon the other night.

[Aliska]

I took a photo of one. several years ago now. I looked up and there it was so I ran to get my camera. It’s on my desktop at another location or I would post it.

[Fledermaus]

I explained this to some idiot FReeper that called me an moron.

[Bearshouse]

Stunning.

[BipolarBob]

https://www.youtube.com/watch?v=7rYN3lmpSyk

[Salamander]

I can’t even imagine the context for that.

o_O

[Vaquero]

Moon dog

[mylife]

Sun dogs are a real trip.

[Larry Lucido]

Does it work with a red moon?

[fieldmarshaldj]

You haven’t made your bones on FR until someone calls you a moron. ;-D

[Fledermaus]

I have lots of bones.

[huldah1776]

we called it a “snow ring”. the bigger the ring, the better the chance for snow. This shot is being added to my collection. THank you so much since I am now in the south and do so miss walking in the snow like my family did today in the philly area.

[marktwain]

we called it a “snow ring”. the bigger the ring, the better the chance for snow. This shot is being added to my collection. THank you so much since I am now in the south and do so miss walking in the snow like my family did today in the philly area.

It is an optical phenomena based on a layer of ice crystal cloud in the upper atmosphere.

The angle of the ring(s) are always the same. The brightest and most common, as I recall, is a 22 degree halo, the next is the 46 degree halo. There are only the two.

They apply to both the sun and the moon.

Depending on the angles, all partial rings can be seen. They are often known as "sun dogs", seen as bright spots on both sides of the sun.

[dsc]

I’m going to go out on a limb and call that “art.”

[Vaquero]

Yup. Seen both ‘dogs’

[mylife]

Me too.

[ETL]

Any ideas on what the story is with the footprints in the snow? Looks like it was two small animals walking together then separating, each going to a different tree. Either that or two little guys were walking through the wilderness drinking beer and needed to ‘use’ the first set of trees they came upon.

Warning: never eat yellow snow