Cloudy sky, cloudless circle?

[fromdownunder]

I'm not sure if this belongs here, or in the scepticism forum. I am recounting what I saw one night about a year ago. I am not wooing about it, or anything else. It was interesting and fascinating to see. I just wish to establish whether or not this is a relatively common phenomena, and has a scientific explanation, or if not, what I may have seen.

I went outside fairly late one night for reasons I cannot even recall. It was a cloudy night, and the cloud seemed to extend everywhere. (I need to add that I went out a couple of times later during the same evening and saw the same thing - it was interesting enough to think and wish to see - is it still there?)

There was a full moon, and (from my point of view, obviously) there appeared to be a cloud free perfect circle about 1 - 2 foot (from my viewpoint) around the moon in the sky.

So what I saw was moon (normal size), 1 - 2' "perfect" circle (no cloud) surrounding it , with the moon appearing pretty much dead centre to this, and then cloud everywhere else.

Is this some sort of known event with which I am unfamiliar?

Norm

[steve s]

The moon would only look dead-center from your position. Moving a mile or two in any direction would change the moon's position relative to the circle. The fact that other people would not have seen the same thing you saw means that this isn't some sort of "phenomenon." You just happened to catch it at the right time and the right place.

Steve S.

[Gravy]

Is it possible that the circle wasn't cloud-free? Optical halos around the moon are common, and are usually caused by refraction of light in ice at high altitude clouds. Some examples. (http://images.google.com/images?hl=en&q=moon+halo&btnG=Search+Images&gbv=2)

steve s' explanation also makes sense.

[rwguinn]

It was likely mstly an illusion--only appearing circular due to the "round" moon being bright enough to wash out raggediness (:))
Or, it is possible the Mother Ship was hovering just over you with the invisibility and repellor shields "On".
Happens in Roswell, NM a lot. Whole state coveredin clouds, except for the hole over SE New Mexico...

[casebro]

Nah. The clouds you saw just weren't that thick. The full moon was reflecting enough light to shine through them. The dark 'hole' was an optical illusion- less light there than from either the moon or the clouds, so it appeared to be a window.

[fromdownunder]

OK, that all makes sense, except the Mother Ship bit.

Hhhmmm, maybe I should argue that it did have something to do with the mothership and set up my own UFO lecture circuit. :-)

Thanks for the responses.

Norm

[Mel Odious]

I've seen what you're describing myself on several occasions over the years, though I don't know how common it really is. My conclusions about what I was seeing were exactly the same as casebro's explanation - bright moonlight shining through a thin cloud layer.

When you're standing in fog, you know how there seems to be a circle of clearness all around you, and if you look up, sometimes you can see a little opening of blue sky if the fog isn't thick? I suspect that the thin clouds in the sky were no more dense than a modest fog, which allowed the moon to shine through clearly. At least that's my best guess.

[Crossbow]

I'm not sure if this belongs here, or in the scepticism forum. I am recounting what I saw one night about a year ago. I am not wooing about it, or anything else. It was interesting and fascinating to see. I just wish to establish whether or not this is a relatively common phenomena, and has a scientific explanation, or if not, what I may have seen.

I went outside fairly late one night for reasons I cannot even recall. It was a cloudy night, and the cloud seemed to extend everywhere. (I need to add that I went out a couple of times later during the same evening and saw the same thing - it was interesting enough to think and wish to see - is it still there?)

There was a full moon, and (from my point of view, obviously) there appeared to be a cloud free perfect circle about 1 - 2 foot (from my viewpoint) around the moon in the sky.

So what I saw was moon (normal size), 1 - 2' "perfect" circle (no cloud) surrounding it , with the moon appearing pretty much dead centre to this, and then cloud everywhere else.

Is this some sort of known event with which I am unfamiliar?

Norm

It sounds like there was a high, thin layer of cirrostratus clouds overhead that caused some lunar refraction which is what formed that halo about the Moon.

This sort of thing occurs from time to time and is quite natural, and rather beautiful.

[Dogdoctor]

I always called those moonbows and thought they were due to moisture in the air not in the form of a cloud. On a really good clear night you can make out faint rainbow patterns in the white. I have seen this numerous times.

[LTC8K6]

Hole Punch clouds are not that uncommon, either.

[Hatchet]

Check out the atmospheric optics web site. You will probably find an explanation for what you saw there. From your description my guess is a moon halo.

http://www.atoptics.co.uk/halo/circmoon.htm

Cheers.

[Crossbow]

I always called those moonbows and thought they were due to moisture in the air not in the form of a cloud. On a really good clear night you can make out faint rainbow patterns in the white. I have seen this numerous times.

Pardon me, but moonbows are actually rainbows that are seen using moonlight as opposed to sunlight. I have had the good fortune to see moonbows as well as rainbows.

Both are formed by the refraction of falling rain.

In the case of the cirrostratus clouds, the refraction is caused by ice crystals.