Oculomotor Micropsia

 

Oculomotor macropsia tricks us into believing that the horizon moon looks angularly larger.  If we judge the two moons to be about the same distance away, we are further tricked into believing that the horizon moon has a larger linear size.  If we somehow judge that the two moons are of the same linear size, we will believe that the horizon moon looks nearer to us than the zenith moon.  In most cases, a combination of these factors occurs due to several different sets of distance cues competing for perceptual dominance and hence clouding our judgement.  Psychologists call this cue-conflict.