this post was submitted on 25 Nov 2023
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The Moon just now in the UK. No idea what is creating the halo

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[–] [email protected] 38 points 11 months ago (2 children)

That would be a 22° halo, a fairly uncommon atmospheric phenomenon where light refracts through hexagonal ice crystals in the atmosphere resulting in an average deviation from the angle it comes in at by around (funnily enough) 22°.

There are lots of other interesting atmospheric phenomena including sundogs, moonbows, and the much rarer 46° halo!

[–] [email protected] 4 points 11 months ago* (last edited 11 months ago) (2 children)

Oh nice, I've seen this before in Florida but was unable to capture it in my phone's camera. Didn't realise it had a name!

sundogs

You're just making things up now XD

[–] [email protected] 9 points 11 months ago (1 children)

Though it sounds silly, sundogs are the name of an actual optic phenomena. They appear as bright spots on either side of the sun, aligned with where the halo may appear. Hence, they are "dogging" the sun.

[–] [email protected] 4 points 11 months ago

Yarp, I looked it up. The etymology section is fun, I like to think there's no real meaning behind it, someone just called it that and the name stuck.

[–] [email protected] 3 points 11 months ago

No, that’s updog.

[–] [email protected] 3 points 11 months ago (1 children)

the much rarer 46° halo

If that's the really huge halo that seems to take up most of the sky, I've only seen that perhaps 3x in my life.

Are they not collectively called coronas, in your part of the world? They are here.

[–] [email protected] 3 points 11 months ago* (last edited 11 months ago) (2 children)

Yeah that's the one! Only seen it once (coinciding with a supermoon which was frankly surreal).

Coronas are a bit different I believe, though another one of the same group. I've always just called them their individual names, with coronas being tighter and more spectrally-distorting than halos. Maybe the only other collective name I've heard would be the minimally descriptive "atmospheric phenomenon" but that's no fun at all.

Edit: Just took a brief look and indeed coronas are related but formed by refraction through water droplets rather than ice crystals! Cool to know!

[–] [email protected] 3 points 11 months ago (1 children)

Not refraction, but diffraction and interference. The droplets (or ice particles or in some cases even pollen) get so small that light stops behaving like rays at those scales.

[–] [email protected] 1 points 11 months ago

Ahh yes, that's the one! Thank you

[–] [email protected] 1 points 11 months ago

Thanks, that's interesting! Colloquially they're just called coronas here I think, but it sounds like a misnomer.

[–] [email protected] 21 points 11 months ago (1 children)

We saw the same tonight as well from northern Italy about 2 hours ago. The moonlight interacts with ice crystals in the air and creates this rainbow / halo 🤯

[–] [email protected] 6 points 11 months ago

Yeah, if there’s an atoptics (I think that’s the word) community, they’d be all over that!

[–] [email protected] 19 points 11 months ago (3 children)

Ice crystals. The old-fashioned name for it is a corona, and according to folk wisdom, a corona of that size is usually a harbinger of cold weather coming.

[–] [email protected] 7 points 11 months ago* (last edited 11 months ago)

This is the 22° halo. A Corona is an entirely different phenomenon caused by diffraction and interference of light around tiny water or ice particles, or other such particles of similar size. Halos on the other hand are formed by refraction. Here's another great resource about coronae (and pretty much every other atmospheric optical phenomenon out there).

You're correct about halo phenomena being caused by ice crystals. As such, they are most often observed when there's Cirrostratus in the sky, and that in turn is often the result of an incoming warm front. The Cirrostratus may start to thicken into Altostratus and Nimbostratus, so overcast and rainy would be the safest bet.

[–] [email protected] 6 points 11 months ago (1 children)

colder and wetter weather on the way, is what i was told

[–] [email protected] 2 points 11 months ago

I wonder if it varies regionally?

Where I live, cold almost always comes with some degree of wet, whereas wet doesn't always come with cold because we get the tail end of tropical cyclones.

[–] [email protected] 0 points 11 months ago* (last edited 11 months ago)

Thanks for sharing this. Here's one that I saw a while back

[–] [email protected] 12 points 11 months ago (1 children)

Jupiter just hangin on the right

[–] [email protected] 3 points 11 months ago (1 children)

I could see it this week even in the middle of London

[–] [email protected] 2 points 11 months ago

Yeah same can see it from Hornsey

[–] [email protected] 9 points 11 months ago (1 children)

I just took a picture of the moon, came out pretty good.

[–] [email protected] 1 points 11 months ago

Wow that really is good

[–] [email protected] 6 points 11 months ago (1 children)

That's just an even bigger moon behind it

[–] [email protected] 3 points 11 months ago

It's moons all the way down.

[–] [email protected] 3 points 11 months ago (1 children)

Don't read any of the other explanations, they just spout off the same thing they want you to think!

I did my own research, it turns out this is due to ice crystals. The inside of the dome set on top of the flat earth is covered by LCD displays. These displays get cold in wintertime and ice crystals form within the displays. This causes all sorts of visual glitches, like these halos around the moon. When it warms back up the ice crystals go away and the moon looks normal again.

Don't let people fool you with bullshit stories about ice crystals in the so called atmosphere. It's a totally made up story, with just enough truth in it to make it believable.

[–] [email protected] 3 points 11 months ago
[–] [email protected] 3 points 11 months ago (1 children)

back before internet days, me and the boys got the fear while out smoking, seeing this in the night sky.

[–] [email protected] 1 points 11 months ago

that's when you start howling and chase the evil spirits away man.. oh right you said smoking not drinking..

[–] [email protected] 2 points 11 months ago
[–] [email protected] 2 points 11 months ago

"A ring around the sun or moon, means that rain will come real soon." Old sailors adage.

[–] [email protected] 1 points 11 months ago (2 children)
[–] [email protected] 2 points 11 months ago

Here is an alternative Piped link(s):

We Like The Moon

Piped is a privacy-respecting open-source alternative frontend to YouTube.

I'm open-source; check me out at GitHub.

[–] [email protected] 2 points 11 months ago

Well, I mean, it is close to us.

[–] [email protected] 1 points 11 months ago

Have Spartans recently landed nearby perhaps?

[–] [email protected] 1 points 11 months ago

I took the same picture walking the dogs earlier!

[–] [email protected] 1 points 11 months ago

Also that's Jupiter on the right, we got Uranus on Friday

[–] [email protected] -1 points 11 months ago* (last edited 11 months ago) (1 children)

No idea what is creating the halo

If not the cloud cover or other atmospheric conditions, the lens of the camera the image was taken with. Was the halo visible to the naked eye or only in the photo?

[–] [email protected] 3 points 11 months ago (1 children)

I'm not op and I'm not near them but I saw the same halo with the naked eye last night with zero clouds.

[–] [email protected] 2 points 11 months ago

If you're far enough north, ice crystals in the atmosphere create a halo like that.

[–] [email protected] -2 points 11 months ago

It's just moonlight shining through the buildup of the day's chemtrails.