What effect causes a full moon low on the horizon to appear exaggeratedly large, regardless of whether it is a Supermoon?

Answer

The moon illusion

The exaggerated size perceived when the Moon is near the horizon is an optical trick known as the moon illusion, where the eye compares the Moon to familiar foreground objects.

What effect causes a full moon low on the horizon to appear exaggeratedly large, regardless of whether it is a Supermoon?
astronomyOctoberlunarfull moonHarvest Moon