What is the Autumnal Equinox?
The September Equinox, also known as the Autumnal or Autumn Equinox, is set to take place on Monday, September 22, 2014 at 7:29 PM PDT. On this day summer officially turns into fall for those of us in the Northern Hemisphere.
The arrival of the autumnal equinox, marks the time of year when day and night are roughly equal in length. The word equinox comes from the Latin word for “equal night.” After September 22nd, the North Pole will begin to tilt away from the sun and our evenings will become increasingly darker in the run up to the Winter Solstice – the longest night of the year.
Due to differences between the calendar year and the tropical year, the Autumnal equinox can occur at any time from the 21st to the 24th day of September. We associate many good things with this time of year such as changing leaves, the smell of apple pie, cozy warm scarves, ripe pumpkins and the Northern Lights.
Earth’s four seasons — winter, spring, summer and fall — are determined by equinoxes and solstices. The fall and spring equinoxes are the only days of the year in which the Sun is directly overhead at noon. The sun will continue on its path southward for the next three months, reaching its southernmost point on Dec. 21, the date of the “Winter Solstice.” In the Northern Hemisphere, the days become shorter, the nights longer, and the temperature colder. You can see the sunrise, sunset and day length shown here. Sunrise, sunset and day length around September Equinox 2014
Autumnal Equinox Harvest
Traditionally, the autumn equinox is the celebration of the harvest – fruits and vegetables grown over the summer are collected in preparation for the coming winter months. For three consecutive nights the moon will appear at nearly the same time. This “Harvest” Moon is bigger and brighter – allowing for easier harvesting. It also gives the impression that the moon is closer to earth – even though it’s not. The Harvest Moon usually appears yellow, orange, or red because it must pass through more dust and cloud particles that scatter blue light, letting only the red pass through.
Photo by Steve Petrucelli, Flickr
Autumnal Equinox Customs, Celebrations and Phenomenon’s
Only a few remnants of the esoteric meaning of the autumn equinox continue today. Many traditions formed in the times of ancient peoples were passed down to civilizations and cultures that have added their own veneer. There are, however, still traces found here and there in legends and myths even if somewhat distorted over time.
Many early cultures and religions celebrated the autumn equinox with practices found in the cycles of nature and the alignment of our planet in the solar system. Some of the more interesting ones include:
- The Great Pyramid in Egypt functioned as an enormous sundial and accurately marked the annual dates of both the solstices and the equinoxes. Two of its faces are orientated precisely due east and west, which are the exact points of the rising and setting sun, only on the spring and autumn equinoxes.
In Chichen Itza, Mexico during the spring and autumn equinoxes the sun creates an undulating pattern of light on the nine terraces El Castillo that display seven triangles of light. This light links up with a stone serpent head at its base of the pyramid. As the sun sets on the autumn equinox, the scales undulate and eventually disappear, giving the visual effect of the serpent descending the nine terraces of the pyramid. At the spring equinox the effect is of the serpent ascending the terraces.- The Pyramid of the Sun at Teotihuacan, Mexico faces the exact point on the horizon where the sun sets at the spring and autumn equinoxes.
- In Greek mythology this time of year is associated with the goddess Persephone who returns to the underworld to be with her husband Hades.
- The Romans celebrated the Fall Equinox dedicating this time to Pomona, goddess of fruits and growing things.
The French First Republic was proclaimed and the French monarchy abolished on September 21, 1792. The following day was the fall equinox and it became the first day of the “Republican Era” in France- In the United Kingdom a traditional harvest festival was celebrated on the Sunday of the full moon (Harvest Moon) closest to the September equinox.
- Aboriginal Australians have had a good knowledge of astronomy and the seasons. Events such as the September equinox (which is a spring equinox in Australia) played a major role in the oral traditions of the Indigenous Australian culture.
- In Chinese culture, the Mid-Autumn Festival is celebrated on the 15th day of the 8th lunar month, often near the autumnal equinox day. This is an official holiday in mainland China, Hong Kong, Taiwan and in many countries with a significant Chinese minority. It celebrates the abundance of the summer’s harvest with mooncakes.
In Japan, Higan, or Higan-e, is a week of Buddhist services observed during both the September and March equinoxes. It is customary to visit the temple to present offerings to the principal image of Buddha as well as the family ancestors and refocus on the six paramitas (giving, right behavior, endurance/patience, endeavor/effort, meditation, & wisdom)- In Korea, Chuseok is a major harvest festival and a three-day holiday celebrated around the Autumn Equinox.
- The equinox marks the first day of Mehr or Libra in the Iranian calendar. It is one of the Iranian festivals – Jashne Mihragan.
And so the summer goes – the Autumnal Equinox is here
Trees snapping and cracking in the autumn indicate dry weather. There’s an old weather proverb that says, “If autumn leaves are slow to fall, prepare for a cold winter.”
Although many observances and rituals of the equinox come from a far more simplistic time, many still represent the foundations of our modern way of life – and in a much deeper sense, the rhythms of our existence.
From a scientific point of view, here are a couple of videos worth watching.
How an Equinox Looks From Space
TEDEd The moon illusion
Looking for an app to watch the current position of sun and moon online? Take a look at this iPhone & iPad app: Day and Night World Map – Watch the sun move across the sky.