Originally posted by wolfgang59
Why does the moon look substantially larger when close to the horizon than at its zenith?
I dont know the answer and something more detailed than "its an optical illusion" would be nice!
maybe you are confusing "illusion" with "delusion"
the optical illusion is very real and is based on the way our brains interpret the physical world around us. note that your questions says, "why does the moon APPEAR larger" not "why is the moon ACTUALLY larger" which, of course, it isn't. in fact, as pointed out above, it is actually somewhat smaller due to being more distant by the radius of the earth, as previously stated, and, just a little bit vertically elongated by the lens effect of the atmosphere, but still, the same size as far as our eyes physically process the image at the retina.
So, what would be a delusion? that would be believing that the cow actually jumped over the moon - very possible - if the moon is setting on the horizon! still, the cow, while jumping, and the moon, while setting, and you while sitting there pondering the larger size of the moon and believing that there is more to it all than an optical illusion, happens to believe that the cow actually did jump over the moon while the moon was growing larger and that he is actually in love with you at that moment and you will live happily ever after.
wait. i think the moon gets bigger. the cow did jump over the moon. and he really did love me. life just had to go on, i suppose. oh well. forget it. i don't know either.