moving moon

An ancient Assyrian/Babylonian belief was that “A woman is fertile according to the moon.” The notion was widespread in many cultures and misconceptions about fertility and birthrates cross continents and centuries.

Eugen Jonas, a Slovakian psychiatrist, created a method of birth control and for predicting fertility that was more based on astrological superstition than any science. He was following that ancient belief that there are more births during a full moon. That is despite the many studies that have failed to find any significant correlation between the full moon and number of births.

And then there are the phases of the moon, menstrual cycles, and fertility.  The average menstrual cycle is 28 days and that is close to the lunar cycle. Close enough in ancient times to create a correlation. But women’s cycles vary from woman to woman and month to month. The length of the lunar month is a consistent 29.53 days.

Since the moon really does affect the ocean’s tides, it must be powerful enough to affect the human body – which is mostly water – too. That’s another old myth. The lunar force is actually a very weak force.  Astronomer George O. Abell claims that a mosquito would exert more gravitational pull on your arm than the moon would. Nevertheless, many people believe that the moon not affects us but can cause earthquakes.

The tidal force of the moon on the earth actually depends on its distance from earth, not its phase.  I wrote this weekend about the full Moon, the “supermoon” and apogee and perigee (when the moon is closest).  We have higher tides at the new and full moons, but it is because the sun, Earth, and moon are in a line and the tidal force of the sun joins that of the moon at those times to produce higher tides.

I love the Moon and I write about it her quite a bit. I enjoy the romance and lore of the Moon. But I also like knowing the science.