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reviewed Close Space time and aging
Apr
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comment Space time and aging
This question does not appear to be about astronomy, within the scope defined in the help center.
Apr
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Apr
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reviewed Approve Circular formation around the moon
Apr
20
revised Circular formation around the moon
rolled back to a previous revision
Apr
20
comment Circular formation around the moon
@pela Ah OK I took the liberty of creating a drawing for you and edited it into your answer as a new revision, then reverted to your previous one. I tried to follow your style the best I could.
Apr
20
revised Circular formation around the moon
edited body
Apr
20
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Apr
20
comment Circular formation around the moon
@pela I'm referring to your new drawing. The angles you evaluate are wrong. The Moon isn't roughly 2x the distance (even less actually, since you start measuring from its circumference and it would have at least some width) from the clouds / atmosphere. Here are the Earth and the Moon and the mean distance between them to scale. Can you imagine the size of the Earth you'd need, or the height of its atmosphere, for those angles you draw to be true?
Apr
20
comment Circular formation around the moon
I don't understand why don't you simply mark the outbound angle (from the observer towards the halo) as 22° one on your drawing? That's the angle we're measuring here. The two angles you marked now could be anything, it's just a coincidence that the Sun and the Moon cover more or less the same solid angle (their angular diameter is 31.6 to 32.7 and 29.3 to 34.1 minutes, respectively) when observed from the surface of the Earth. Plus, the angles you mark aren't 22°. Considering Sun's and Moon's distance, they would be nearly identical to half their angular diameter.
Apr
20
comment Circular formation around the moon
You might be interested in this APOD photo. It shows that the 22° halo is an atmospheric effect.
Apr
20
reviewed No Action Needed Circular formation around the moon