Autumnal equinox 2021: When is the first day of fall?

For those who love fall, the long wait is almost over.

On Wednesday at 3:20 p.m. ET, fall will make its way onto our calendar when the autumnal equinox happens.

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What is the autumnal equinox? It is the day fall begins in the Southern Hemisphere. Here are some things to know about it:

1. An equinox happens when there is an alignment between the sun and Earth in which the sun appears positioned directly above the Earth’s equator. During the autumnal equinox, the sun rises due east and sets due west.

2. The word “equinox” comes from the Latin word meaning “equal night.” It refers to the roughly equal amounts of daylight and nighttime that will happen on Wednesday.

3. There is an ancient Maya step pyramid — El Castillo at Chichén Itzá in Mexico — where at sunset on the autumnal equinox, sunlight hits the building’s staircase and creates a snake-like shape that appears to slither up the stairs. Check it out here:

4. From Sept. 22 onward, the days will get shorter — progressively less sunlight each day — until the Winter Solstice happens in December. Then, the process starts in reverse with progressively more sunlight each day.

5. As far as meteorologists are concerned, the first day of autumn has already happened. It was on Sept. 1. Meteorological seasons fall on Sept. 1 for fall, Dec. 1 for winter, March 1 for spring and June 1 for summer.

6. Is it true you can balance an egg on its end on a day that is an equinox? If you can, it has nothing to do with the equinox. The amount of sunlight the Earth gets has nothing to do with gravity. That you can balance an egg on its end on the day of the equinox is a myth — unless you happen to be a good egg balancer.

Sources: National Geographic; Encyclopedia Britannia