Our next question involved gazing at the moon. We have all exclaimed over the beauty of a rising full moon. Perhaps you have also noticed that the moon does appear larger when it is seen close to the horizon. It is especially noticeable when the moon is full.

We might reason that this is because the moon is closer to us when it is full, since things do appear larger when they are closer. However the moon's distance from us varies too little to account for an increase in apparent size.

Another good guess is that the atmosphere magnifies the image of the moon, playing a trick on our eyes, but the atmosphere is not to blame. Indeed a trick is being played on our eyes, and it is due to the Ponzo effect.

Our eyes are always trying to see an object in relation to another object. When we are outside, we usually use the horizon to judge how far away something is, or how large it is. When we have no horizon to use, such as when the moon is high in the sky, it appears smaller. When we see the moon near the horizon, it looks larger because we see it in relation to trees and buildings; this is the Ponzo Effect.

Q 6) What is a Honeymoon?