Over the millennia, numerous feasts, sacrifices, and wild orgies have been associated with worship of the moon. We’ve built temples and ziggurats, altars and pagodas, artefacts and ornaments in honour of the moon. The latest theories about the origins of Stonehenge regard the monoliths as part of a lunar-worshipping, hunter-gatherer society that was lamenting the advent of agriculture and thus an increasing dependence on the sun.
Shelley’s depiction of his fellow poet, Keats, as Endymion is based on the charming story of a young Greek lad who makes love to the moon goddess, Selene, who puts him to sleep eternally so that he may be forever young.
Arctic myths tell us how an Inuit woman lost her husband and decided to get hitched to the moon by stealing into his house in the dead of the night. One would think that’s from where we get the word honeymoon. But, in fact, the word “honeymoon” is based on an ancient custom of drinking honey wine for a month after the marriage ceremony.
We have undoubtedly been fascinated and perplexed by the moon, but not enough, it would seem, to stop us from endowing the moon with all sorts of anthropomorphic qualities. The moon has been appropriated into almost all our myths and legends. The Incas depicted the moon as the sun’s wife. The ancient Egyptians believed the moon was the sun god Amon-Ra’s offspring. The ancient Mesopotamians, on the other hand, believed that the moon god, Nanna, was the father of the planet Venus. In Greek mythology, the moon goddess, Artemis, was twin sister to the sun god, Apollo. Our friends the Aztecs also believed that the sun god, Uitzilopochtli, and the moon goddess, Coyolxauhqui, were brother and sister. But they had a more dastardly conception of the sun and believed that the sun murdered the moon. The Khoikhoi people of South Africa worship the moon to this day.
Tiv, Sin, Luna, Hecate, Diana…the names of moon goddesses are legion. Alas, we have but one moon and not many myths have depicted the moon as a daughter of the earth. For, in many ways, our own planet earth engendered the moon.
In the very early days of the earth’s formation, a gigantic meteor, or proto-planet crashed into the earth. The earth was nearly destroyed by this cataclysmic impact and a huge amount of material from the primordial earth was smashed and blasted out into space. All this early earth material—the dust, the rocks, the debris—continued floating round the young earth until it finally coalesced to form our moon. We know this because the rocks brought back from the moon have the same density as the rocks in the upper mantle of the earth. The rocks on the moon have also been dated and are almost the same age as the earth and are similar to volcanic and other igneous rock found on earth. What is fascinating about some rocks found on the moon is that they are slightly magnetic, which would indicate that they solidified in a place that had a much stronger magnetic field than the moon.
What is strange about the moon is that it always presents the same face to us on earth even though both the earth and the moon rotate. The other side, called the far side or the dark side of the moon, was hidden from us—hidden until our lunar probes managed to chart it in the 1960s. The moon and earth have synchronised their rotational periods over the vast geological time since their formation. There are people who believe the moon looks different from different places. This is an erroneous opinion. A knowledge of high school trigonometry will explain why: The moon is 384,400 kilometres from the earth and its diameter is 3,480 kilometres (which is just one-fourth that of earth). At this vast distance, any two spots on earth would form a very small angle with the moon. So the perspectives of two people watching the moon at the same time would be more or less the same—even if they are separated by vast distances on earth. If they were watching the moon at different times, it would still show the same face because it is the same moon that passes over Asia on to Europe and then to America. The most important point to remember is that we see only one side of the moon. So it has to be the same when viewed from anywhere on earth.
We are awed by the spectacle of the moon covering the face of the sun during a solar eclipse. The only reason this happens is because the moon has just the right circumference and is at just the right distance away from the sun to obscure it completely. However, on a geological timescale, we live in a window of opportunity. This almost perfect eclipse has not always been the case and will not always be the case. In the past, the moon was much closer to the earth than it is now. The moon has been receding. In the distant future, the moon will be farther away; we will no longer have a perfect solar eclipse and the phenomenon of the Bailey’s beads (those points of sunlight that shine on the edge of the moon before totality) will no longer be visible.
The lunar eclipse isn’t really an eclipse. Technically speaking, it is an occultation of the moon—caused by the earth coming between the sun and the moon and casting its shadow on the moon. It should really be called a lunar eclipse if the phenomenon is being observed from the sun. When viewed from the sun, the moon would be eclipsed by the earth.
The moon turns dull red at the totality phase of a total lunar occultation. This is because even though no light from the sun reaches the moon, reflected light from earth does manage to illuminate the moon. As this light travels through the earth’s atmosphere, blue light is scattered away, leaving behind red light.
A strange thing about the moon is that it appears larger when close to the horizon. It is an illusion, we know. But what causes the illusion? The explanation is not hard to come by. The earth’s atmosphere is, like the planet, curved. Air can distort light—as anyone who has seen a shimmering mirage in the distance on a hot day will testify. The moon appears larger near the horizon because the humidity combined with the effect of the earth’s atmosphere acts as a magnifying lens. The same effect may be observed when the sun is low on the horizon during dawn and dusk. Both the sun and moon look somewhat pear-shaped when they are close to the horizon. This is because the lensing effect is more pronounced lower down—closer to the horizon, where there’s more atmosphere and more humidity.
There are other explanations for the horizon effect, like oculomotor macrospia and oculomotor microspia and the Ponzo illusion, but the lensing explanation is the soundest.
