At precisely 2:20 p.m. today, the sun will cross from north to south and pass directly over the celestial equator, an imaginary line in the sky above the Earth’s equator. At this precise moment, the Earth’s rotational axis will not be tilted toward or away from the sun. Yes, the autumnal equinox, also known as September or fall equinox, will occur, fall will be in the air, and the transition from summer to fall will begin.Soon there will be crisp nights, a display of colorful leaves, the aroma of pumpkin spice everywhere, sweatshirts, and bonfires. It is a welcome change that many look forward to each year.
The word equinox, which is derived from the Latin word aequus, meaning equal, and nox, meaning night, has many believing there is an equal amount of 12 hours daylight and 12 hours of nighttime. This, however, is a common misconception. Most places on Earth enjoy more than 12 hours of daylight on this particular day. There are two reasons this occurs: the way sunrise and sunset are defined and the atmospheric refraction of sunlight.
The September equinox is the second equinox of the year, with the first occurring around March 21 every year. The autumnal equinox usually occurs on Sept. 22 or Sept. 23. It does, however, rarely occur on Sept. 21 or Sept. 24. A Sept. 21 equinox has not occurred in several millennia, but will happen twice in the 21st century in 2092 and 2096. The next Sept. 24 equinox will take place in 2303, with the last time it occurred being in 1931.
While many places around the world choose to commemorate fall equinox all day with festivals, celebrations, and parades, it is actually just a moment in time.Nights will begin to get longer until Dec. 21, the shortest day of the year. Because of time zones, the equinox can occur on different days for different locations. It is also interesting to note that Saturn has equinoxes every 15 years because it takes almost 30 years for Saturn to orbit the sun.
With the autumnal equinox preparing to take place, the northern hemisphere will experience what is known as a Harvest Moon very close to that time. A Harvest Moon is what we label as the full moon closest to the September equinox. Autumn full moons are different from others in that they rise closer to the time of sunset and give dusk-till-dawn moonlight for several evenings in a row. In 2021, the Harvest Moon occurred just two days ago on Monday, Sept. 20.
With the September equinox bringing less daylight hours, animals begin to experience biological changes to prepare for the colder weather. Animals begin storing more food, migrating, or looking for a place to hibernate. The autumnal equinox also marks peak viewing of the northern lights, sometimes called aurora borealis, for those in the northern hemisphere.
So if you originally thought the September equinox was simply when fall begins, think again. It is so much more. If you can’t wait for those temperatures to drop into the 50s, you are in luck. It is projected to happen in Blount County tomorrow night.
Happy fall y’all!