For centuries, the moon has been a source of comfort to many. It was seen as a sort of guardian that watched over the earth when the sun had gone away, and would relinquish his guardianship once day came back again. We now also know that the moon is incredibly important for our wellbeing on earth; without the gravitational attraction of the moon our planet would not have formed in the shape it is now; indeed the moon plays a massive part in stabilizing the motion of the earth as it passes through space. The moon also plays a part in the sea tides; determining when the tide goes in and out. However, its main purpose for millennia has been as a time keeping device.

The lunar cycle is 28 days long; exactly 4 weeks and goes from full moon, to no moon to full moon in that time. The reason this occurs is because the moon passes into the earth’s shadow gradually slowly obscuring itself. This process has taken place since time began with exactly the same regularity. Because of this the moon is an excellent device for telling the time of the month and was the world’s first calendar. In the days of sacrifices it was the cycle of the moon that determined when the animals (or humans) would be sacrificed. Nowadays of course, it plays a much smaller role, yet the lunar cycle still manages to amaze children every day; all marveling at how it seems to change its shape.