when moon is low on the horizon,it appears larger than when it is overhead, yet the actual size of the moon's image on the retina is the same regardless of position in sky.illusion result of size constancy.
when moon is low, it appears to be farther away than when it is overhead. this effect results from visual cues for distance. compared to trees and other objects on the horizon, we perceive moon to be far away. when we look at the moon overhead, we have no visual cues for distance