Why does the moon look bigger when it's near the horizon?

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slash brain Stuff. That's Audible podcast dot com slash brain Stuff. Hi, ammercial brain With today's question, why does the moon look so much bigger when it's near the horizon. This question has been pondered for hundreds, if not thousands of years. Most scientists today agree that the reason the moon looks bigger is purely in our minds. Our mind interprets the

things we see in interesting ways. For example, if you look at any door frame, you can see that it's rectangular, But if you were to sketch the actual outline of the door frame from the angle that you're looking at it, most likely you would sketch a trapezoid. Your mind adjust the door so that you perceive it as a rectangle from whatever angle you look at it. That theory is

called shape constancy. There's also something called size constancy. You've probably seen optical illusions that take advantage of this effect. These illusions feature two images that are identical in size, but one looks much bigger than the other because is the way the picture is drawn. This happens because your mind sees queues that cause it to see one image as farther away than the other image, So your minded just the size of the first image to make up

for the increased distance. Size constancy is happening all the time. If you look down the street and see a sports car about fifty feet away and behind it, about a hundred feet away a big suv, you know that the suv is bigger, even though it produces a smaller image on your retina. One theory about the moon illusion says that when the moon is near the horizon, we perceive it to be further away from us than when it's

high up in the sky. But since the moon is actually the same size in both cases, our minds make it look bigger when it's near the horizon to compensate for the increased distance. One way you can trick your mind out of the moon illusion is to bend over at the waist and look at the moon upside down through your legs. And alternate of explanation holds that the moon illusion is caused by the way our eyes focus

on distant and close objects. When we focus on the horizon moon, we focus on the moon at a great distance. The overhead moon lacks visual cues that tell us how far away it is, so we focus on the overhead moon as if it's a short distance away. So for now, the right answer is that there's no right answer. But the one thing people agree on is that the moon does not physically change its size or its distance from the Earth as it moves across the sky. It's perceived

size is all in our heads. This podcast is brought to you by audible dot com, the Internet's leading provider of audiobooks, with more than eight thou downloadable titles across all types of literature and featuring audio versions of many New York Times bestsellers. To try Audible free today and to get a free audiobook of your choice, get an Audible podcast dot com slash brain stuff. That Audible well podcast dot com slash brain stuff. The House staff works.

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