Why does a Full Moon look huge when it's rising in the East, but look smaller when it's above the horizon?

The theories presented so far have been pretty much debunked. The following link gives an elaborate explanation of this illusion. But even it fails to explain why we don't see this illusion every time the moon rises. It does not always appear larger at moonrise than when it is higher in the sky. Also, the moon may appear to be different sizes on different nights even in the same location. I'm still looking for a plausable explanation. http://facstaff.uww.edu/mccreadd/

There's some sort of effect that goes on, though it is the same size. I forgot what coin you use, but take one and put it in front of the moon on the horizon, and you can see moonbeams from around the edges, the same is true when you put it against the moon later on. Also... take a picture of the moon in both places, the camera gets rid of the illusion.

It's because when it's near the horizon, it actually looks FARTHER away from you than when it's higher in the sky because it's behind objects that you know to be far away. When it's high in the sky, you don't have any point of reference, so it seems closer. In a similar way, if you were to see two objects that look the same size but you think one is farther away from you, your brain will automatically believe that the one that is farther away is bigger.

This is simple, and the other answers touch on it. The moon remains the same size at all times. However, the points of reference change. In the sky, you see the moon as a certain size. On the horizon, you see the SAME SIZE moon...but you see it in comparrison to houses and trees...which are tiny next to the MOON! And because you know how big a tree or house is, your brain tells you the moon must be HUGE! It is all a matter of what is next to the moon that makes it look big or small.

This is simple, and the other answers touch on it. The moon remains the same size at all times. However, the points of reference change. In the sky, you see the moon as a certain size. On the horizon, you see the SAME SIZE moon...but you see it in comparrison to houses and trees...which are tiny next to the MOON! And because you know how big a tree or house is, your brain tells you the moon must be HUGE! It is all a matter of what is next to the moon that makes it look big or small.

There's some sort of effect that goes on, though it is the same size. I forgot what coin you use, but take one and put it in front of the moon on the horizon, and you can see moonbeams from around the edges, the same is true when you put it against the moon later on. Also... take a picture of the moon in both places, the camera gets rid of the illusion.

It's because when it's near the horizon, it actually looks FARTHER away from you than when it's higher in the sky because it's behind objects that you know to be far away. When it's high in the sky, you don't have any point of reference, so it seems closer. In a similar way, if you were to see two objects that look the same size but you think one is farther away from you, your brain will automatically believe that the one that is farther away is bigger.