---
title: Size of the sun and moon
date: "2006-04-01T12:00:00Z"
categories:
  - links
wp_id: 381
description: I explore the psychological illusion of the Sun and Moon's size. By using a finger at arm's length as a two-degree scale, you can see that four moons actually fit behind your single fingertip.
keywords: [sun, moon, moon illusion, angular diameter, psychological illusion, perception]
---

[The sun and moon look smaller than you think](http://www.shatters.net/forum/viewtopic.php?p=15079&highlight=#15079).

> The apparent large size of the Sun and Moon as we see them in the sky is a psychological illusion. There are several different explanations for this. If you take a picture of the moon with a camera lens that has the same field of view as Celestia, you may be surprised at the small size of its image.

> Here is something you might try: a finger at arm's length is about two degrees wide for most people. That means that you can fit four moons side by side. Go outside and check it. Now have a direct look at your finger indoors. Can you still believe that four moons will fit on it?