Lunacy

Have you ever blamed something on the full moon?

Please stop. For me. It’s bad science.

The phases of the moon, and the full moon in particular, has long been associated with a variety of subjects: crop success or failure, fertility, menstrual cycles, stock market fluctuations, blood clotting, romance, murder, evil spirits, madness, the United States' 2000 presidential elections, and of course lycanthropy.

Why is that?

I don’t know, there’s probably some anthropological reason about people being obsessed with big things in the sky, but that’s not why I’m here. I’m here to give you a response to people who bring up the “scientific” explanation for why the moon affects us, because I refuse to be the only person bothered by this.

It’s supposed to be a sort of “biological tide”. If a person is 80% water, shouldn’t gravity affect the water in us the same as the ocean? Sounds reasonable at first, but no.

First, gravity isn’t only affecting the ocean, it’s pulling on the whole planet. The moon produces tides because, as astronomical distances go, the moon and Earth are relatively close so that the moon's pull on the side closest to the Earth is slightly more than the pull on the other side stretching the Earth into a shape similar to a football. This slight distortion causes the oceans to want to pile up under the moon and opposite to the moon and since the Earth is in rotation in relation to the moon this flow reverses twice a day causing the daily ins and outs of tides.

Second, the idea that people and the earth both have an 80:20 ratio of water to solids is only true of the earth’s surface and tides only occur in unbounded bodies of water. I would think it is safe to say that the human body falls into the bounded-waters class.

Lastly, gravity is affected by the inverse-square law in regards to distance; a change in distance will change the force of gravity proportional to the change squared. This means that gravitational attraction is strongest for objects close together and rapidly decreases as they separate. Tidal force in particular is actually an inverse-cube so the effect of distance is even greater. So while the moon is very large it is also very far away, way too far to have much of an effect on things as relatively small as the human body. So much so that a person standing next to you in line to see TEEN WOLF has over 40,000 times the gravitational influence on you than that of the full moon overhead does.

So please stop blaming things on the moon. (Except for werewolves, that one is all the moon’s fault.)