Question: how come the sun is the highest in the midday

Juan Carlos Lopez-Baez answered on 21 Mar 2014:

Hi @irishleprechaun

Good question! This is because of the rotation of the Earth. See, it doesn’t have anything to do with the Sun being higher or lower, it is how we perceive it from Earth. As you probably know, the Earth rotates. As it rotates, it exposes itself to the Sun. At midday is when the Sun is the most straight ahead. For that reason, it appears as high as it will get in our sky, as we have it directly in front of us.

Of course, you might ask, how comes if its distance to us does not vary we see it raise from the horizon, go up in the sky and then disappear again. That is because of the round shape of the Earth, which makes it appear that way. To see what I mean, you can get a lamp, switch it on and place a tennis ball some distance away. Now draw a cross on the tennis ball (that’s where we will be) and without moving from where it is start rotating it. You will see that the cross on the tennis ball gets the more light when the lamp is straight ahead of it.

By the way, did you know that the Sun will appear at different “heights” in the sky depending on were you are on Earth and the season? This has to do not with the rotation of the Earth, but its rotation around the Sun and the fact that the Earth is round. Get you science teacher to explain it to you, it is very interesting!