Mayan TempleWe have two equinoxes each year around the 22nd of September and the 20th of March, the word “equinox” comes from Latin meaning “equal night”. They are the dates where the length of daylight is exactly equal to the length of night, 12 hours of daylight and 12 hours of darkness. Although the exact amount of daylight is not exactly 12 hours, the equinox is actually the time when the centre of the sun crosses the celestial equator. The exact time of day this happens can be calculated and for 22nd of September 2012 autumn equinox will be at 2:49 pm. The autumn equinox is the sun moving from north to south when the days get gradually shorter in to winter. In the southern hemisphere this date is known as the spring equinox as the days get gradually longer. The autumn and spring equinoxes are also the only two times of year when a person can stand on the equator and see the sun pass directly over head. In the northern hemisphere a person standing on the North Pole would see the sun skimming across the horizon signalling the start of six months of darkness. While a person standing on the South Pole would see the sun skimming across the horizon signalling 6 months of daylight.

The moon also plays a large role at this time of year; the full moon closest to the autumn equinox is traditionally called the harvest moon. Autumn equinox has been celebrated in many cultures around the world through history. Mabon is the mid harvest festival celebrated by the pagans at the autumn equinox when the fields are almost empty and the preparations for winter are about to start. This time is for giving thanks for the plentiful harvest and welcoming the darkness with open arms while giving thanks to the sunlight. Some pagans also celebrated the festival by building a wicker man, which was made from the last stack of corn from the harvest. This was then woven in to the figure of a wicker man or woman before being burned and the ashes spread across the field. It is from this story and the popular 1973 film “The Wicker Man” that the myth of human sacrifice became popular.

The Mayans who were the best astronomers of their age also knew about the autumn equinox and built the El Castillo pyramid with 91 stairs on each side which along with the temple on top equals 365 to represent the days of the year. On the autumn and spring equinox the sunlight shining on the western balustrade of the pyramids stairway, causes 7 isosceles triangles to form, this creates a 120 foot long snake’s body which curves down towards a serpents head at the foot of the stairway.