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To: DBrow
The phenomenon he's refering to is the "moon illusion," an optical illusion by which on any given night the moon appears larger at the horizon than when it is higher in the sky. I recall a whole book about this, written back in the '60's, summarizing the psychophysiological research and other possible mechanisms, but there still is no definitive answer. The illusion persists, unconcerned.
15 posted on 05/04/2012 12:53:00 PM PDT by hinckley buzzard
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To: hinckley buzzard

You’d get the moon illusion for any full moon, though. What will make this one special is, in addition to the moon illusion, the angular size of the disc will be a little bigger.

I took that as the “misunderstood phenomenon”, since we get moon illusion 13 times a year.

Too bad it’s not an eclipse, it would be a long one!

The next eclipse will be an annular, btw, with the moon a little smaller than the Sun in angular terms.


16 posted on 05/04/2012 1:10:04 PM PDT by DBrow
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To: hinckley buzzard

OK I looked it up- this weekend the Moon will have an apparent size a whole 0.1 degree bigger (6 arcminutes over the “average” of 30 arcseconds).


18 posted on 05/04/2012 1:14:46 PM PDT by DBrow
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