In the northern hemisphere, fall will officially begin this year with the autumn equinox on September 22nd.
The Start Of Fall
The autumn equinox doesn’t always fall on the same day of the year. But it does always take place at some point between September 21st and September 24th. Much like the spring equinox, on the autumn equinox, day and night are almost equal in length across the planet. The term equinox comes from the Latin words “aequi,” meaning equal, and “nox,” meaning night.
In the northern hemisphere, the autumn equinox marks the arrival of the fall season. However, in the southern hemisphere, the seasons are reversed, as the earth begins to tilt more directly towards the sun in the southern half of the planet.
The arrival of fall has been celebrated by human civilizations for thousands of years. While ancient cultures didn’t have the same clocks and measuring tools to calculate the minutes of daytime and nighttime, they were able to measure the sun’s position geometrically. They observed the movement of the sun’s rising and setting points each day, marking the summer solstice when the sun reached its northernmost point. The two days when the sun rose exactly due east and set exactly due west marked the spring and fall equinoxes.
Fall Around The World
Throughout history, the arrival of fall has held great significance to cultures around the world. The ancient Greeks believed that the autumn equinox marked the return of the goddess Persephone to the underworld to be reunited with her husband Hades. Persephone’s mother, Demeter, is the goddess of the harvest. Her sadness over her daughter’s return to the underworld was thought to cause the crops to wither until Persephone reemerged in the spring.
In China and Vietnam, fall is greeted with a more joyous tone. The full moon that falls closest to the autumn equinox is celebrated with the Harvest Moon Festival. Also sometimes called the Mid-Autumn Festival, the occasion is often marked by families enjoying a large meal together, similar to the Thanksgiving tradition in America. Other festivities include the lighting of paper lanterns, worshipping the moon with gifts, and eating mooncakes, a traditional Chinese dessert.
The famous landmark, Stonehenge, holds cultural significance related to the changing of the seasons. While there is no confirmation on who built Stonehenge, a popular theory holds that it was constructed by the Druids, members of the learned class among the ancient Celts. Much like the builders of the site, the original purpose of Stonehenge is also shrouded in mystery. But in the 1960s, astronomer Gerald Hawkins suggested that the megalithic stones may have served as an astronomical calendar, with different points corresponding to astrological phenomena like solstices, equinoxes, and eclipses. On the autumn equinox, neo-Druids gather at Stonehenge to perform rituals associated with the arrival of fall.
Have you ever felt like you were able to smell fall in the air? According to meteorologist Matthew Cappucci, fall does have a distinct smell, partially due to the falling leaves. As they decay, the leaves “exhale” gases which Cappucci describes as smelling, “a bit like chlorine or the exhaust of a dryer vent.” The smell of the season has also been linked to the trigeminal nerve, which is responsible for the sensations in the face. When you breathe in, that nerve gets triggered, which can cause the brain to associate the cooler air with a “scent.”
And that’s not the only sense that gets its own fall journey. Despite its reputation for chillier weather and harsh growing conditions, there are several fruits and vegetables that are in-season during the fall. Apples, pears, squash, pumpkins, sweet potatoes, and turnips are all at their peak during the autumn months. If you’re looking for variety, apples could be your perfect fall snack, since there are 7,500 varieties to choose from worldwide.
Fall can have an even more pronounced effect on other species, on top of new smells and flavors to enjoy. Researchers have found that the hippocampus — the part of the brain that handles spatial organization and memory — of the black-capped chickadee can expand up to 30% in the fall. It’s believed that this change in the bird’s brain has evolved to help it to collect and hide massive amounts of seeds that it will rely on during the winter months.
TODAY’S QUIZ YOURSELF
Pop Quiz Hotshot