Eight Myths About the Moon, Part I

Nobody believes it’s made of cheese anymore — hopefully — but plenty of myths about the moon still remain to be skewered.

It should come as no surprise that myths about the moon are as numerous as hairs on a dog. Perhaps the silliest of the modern crop is the claim that NASA’s moon landings were false. All you have to do to prove that one false and zap one of the laser reflectors our astronauts left behind on the lunar surface.

Astronomers do that all the time — but it’s harder to fight all the other modern myths folks have come to believe about our companion in orbit. They keep trying, though. In this two-parter, we thought we’d give them a little help. Here’s the truth behind eight modern lunar myths.

Myth 1: Blue moons are actually blue.

Come now. While you can’t ever discount the possibility of some external factor like volcanic gasses staining moonlight blue, this myth about the moon is otherwise an impossibility. The moon itself doesn’t change color, any more than the next lunar mission will find limburger in the lunar valleys.

A “blue moon” is simply the common name for a second full moon within a calendar month. It’s a coincidence of human recordkeeping. A full lunar cycle takes about 29-1/2 days, while most months are 30 or 31 days long. Therefore, it’s inevitable that we’ll have a blue moon every couple of years.

Myth 2: The moon can affect your emotions.

This myth about the moon has been around a long time. The term “lunacy,” derives from the Latin word for the moon, Luna. In modern times, some authorities have lent the idea credence, with the theory being that since the moon causes tides, it can affect the fluids in your body, changing how you feel.

Well, there’s no indication that any such thing can occur, three thousand years of astrology notwithstanding. Hospital personnel and the police often swear that people are wilder and commit more crimes during the full moon, but repeated statistical analyses of their records show no significant correlations.

Myth 3: A lunar month is exactly 28 days long.

This myth about the moon is almost true, but not quite. The moon’s orbital period (that is, the time it takes the moon to complete one revolution around the Earth) is 27-1/3 days, while the average time it takes to go through its phases is 29-1/2 days. That’s why we get a blue moon on occasion.

Now, you might think that the orbital and phase periods would be the same; and they would be, if the Earth-Moon system were sitting dead in the sky. However, we all revolve around the sun too, so it takes the moon about 2-1/6 days longer to get lined back to up in its original phase than it does for it to revolve around the Earth.

Myth 4: There’s no gravity on the moon.

While astronauts on the moon are obviously much lighter than they are back home, they still have to deal with some gravity. It’s only one-sixth of the Earth’s, though. If you weigh 150 pounds on Earth, you’d weigh 25 on the moon. That’s a big difference, which may be why this myth among many myths about the moon is still with us!