The Ponzo illusion is one possible explanation of the Moon illusion, with objects appearing " far away " ( because they are " on " the horizon ) appearing bigger than objects " overhead ".
22.
Emmert's law is closely related to size constancy, and has been used to investigate the moon illusion ( the apparent enlargement of the moon or sun near the horizon compared with higher in the sky ).
23.
By allowing viewers to move simulated moons toward and away from each other, the scientists demonstrated that the so-called moon illusion seems to be caused by the brain's inability to estimate huge distances in the empty night sky.
24.
The scientist Ibn al-Haytham ( Alhazen ) carried out experiments in visual perception and the other senses, including variations in sensitivity, sensation of touch, perception of colors, perception of darkness, the psychological explanation of the moon illusion, and binocular vision.
25.
Its width is unaltered, so the disk appears wider than it is high . ( In reality, the Sun is almost exactly spherical . ) The Sun also appears larger on the horizon, an optical illusion, similar to the moon illusion.
26.
Moon illusion says " The true angular diameter of the Moon is about 1.5 % smaller when it is near the horizon than when it is high in the sky, because it is further away by up to one Earth radius . "-- Wikicheng 05 : 58, 20 June 2006 ( UTC)
27.
I once brought this up with my physics teacher back when I was still in high school and he wasn't able to give a satisfactory explanation, and suggested that the post-processing of the optical signal in the brain is what makes the object appear smaller, referring to the Moon illusion as an example.
28.
The Moon does appear larger when close to the horizon, but this is a purely psychological effect, known as the Moon illusion, first described in the 7th century BC . The full moon subtends an arc of about 0.52?( on average ) in the sky, roughly the same apparent size as the Sun ( see ).
29.
Between that and the Moon illusion ( note that said illusion also holds for the sun, which has no appreciable difference in observable size, so there really is a psychological component ), I'm not sure the naked eye would actually observe the difference in an equatorial versus England-based viewing . & mdash; Lomn 17 : 47, 4 March 2010 ( UTC)
30.
Murray, et al . ( 2006 ) also noted that the flat illusion pattern they used can represent other classic " size " illusions, such as the Ponzo illusion and, as well, the moon illusion which is a visual angle illusion for most observers, ( McCready, 1965, 1986, Restle 1970, Plug & Ross, 1989, p . 21, Ross & Plug, 2002 ).
