COLUMBUS, Ga. (WRBL) — ‘Tis the season for cooler temperatures, pumpkin spice lattes, and all things fall. Let’s talk a little bit about the science behind the day that starts this great season.

First, let’s talk about the start of fall:
In 2022, fall will begin on Thursday, Sept. 22, at 3:20 PM EDT. This is the exact moment that the sun’s rays will be over the equator, and it happens at the exact same time all across the globe, just in different time zones. The sun will be moving from north to south heading towards the southern hemisphere.

This is also the day that the sun will rise exactly due east and set exactly due west for almost everyone, the exception being those living at the North and South poles. This happens due to the sun moving on the celestial equator, which is an imaginary line above the actual equator. If you were to look up at noon, the sun would appear directly overhead, and this only happens for the spring and autumn equinoxes.

Equal days and nights:
Sort of! 

Equinox is Latin for “equal” and “night,” so you can expect close to 12 hours of daylight and 12 hours of darkness. The reason this happens has to do with the way the Earth is tilted. First, the Earth is tilted on its axis at 23.5 degrees. During a solstice, the tilt of the axis will either point towards or away from the sun. This means that the northern and southern hemispheres trade off when they receive the sun’s light and warmth directly. During an equinox, the Earth’s tilt and even orbit combine in such a way that the axis doesn’t exactly tilt away or toward the sun; thus, the days and nights are somewhat equal, but maybe a few minutes off.

Where do we go from here:
From here our days will become shorter and our nights will become longer. The loss of daylight will continue until we head towards the winter solstice — the day that the tilt of the axis will be away from the sun in the northern hemisphere. This will mark the shortest day of the year (or the longest day of the year in the southern hemisphere). 

The first day of winter will be Wednesday, Dec. 21, 2022.