This is a gorgeous photo of the moon I took a while back. Although the picture doesn’t show it, the moon I saw that night, and what prompted me to take the photo, appeared to be extremely inflated. At first glance I thought that what I was seeing wasn’t the moon, that it was a billboard, or a projection in the sky, but in fact the moon I was seeing was nothing unusual. What I was seeing is called “The Moon Illusion”.
The moon illusion occurs when there’s a low hanging moon. The ‘solstice moon’ is a perfect example. How does that cause the illusion? Well, we know one thing for sure, only humans can see these giant moons. When captured on film and measured, a low hanging moon and your average everyday moon have the same diameter. Also, when you look at the moon, whether it be high in the sky or not, the image formed on your retina is the same size. So it must be the way our brains interpret the information.
There are several theories about how or why this happens, and I’m going to present one. In our daily lives, the horizon represents a very long distance. The zenith, while far away, isn’t as extreme. A bird flying above you is far, but a house you barely see on the horizon is much, much further. If you were to paint a picture, and there were two birds that were painted of the same size, the one painted up in the sky would appear much smaller in comparison to the one on the horizon. Just like on a road, people seem to get smaller the further away they are. Despite the fact that the moon is the same distance away when it’s closer to the horizon, and it’s most certainly the same size, our brains think that it must be a whole lot bigger than it is, if it’s that big when it’s that far away.
After attending school on three continents, Anne Driscoll is finishing her high school career as an unschooler. She now speaks Spanish and Chinese fluently. Anne spends much of her time abroad learning about different cultures. She is currently focusing on Mapuche traditions and lemurs. In addition, she enjoys heliophysics, languages, and 3D printers.