(ABC4) – Spring equinox arrives Sunday, March 20, marking the start of the spring season.
“Equinox” is defined as the time at which the sun crosses the celestial equator, when day and night are of approximately equal length. The word comes from the Latin terms “aequus” (equal) and “nox” (night).
Therefore, spring equinox, or “March equinox,” occurs in the northern hemisphere when the Sun crosses the equator, heading north. The event marks first day of spring for the northern half of the world.
The shift means that the Northern Hemisphere is more tilted toward the Sun, which results in increased daylight hours and warmer temperatures.
Thus, the spring season has earlier dawns and later sunsets.
The amount of daylight per day will continue to increase during the spring until summer solstice in June (when the Sun travels its longest path in the sky), which will be the longest period of daylight that occurs during the year.
For the Southern Hemisphere, the March equinox marks the start of fall, as the southern half of the world is then tilted away from the Sun.
When the Sun passes overhead on the equinox, the tilt of the Earth is zero relative to the Sun, which means that the Earth’s axis neither points toward nor away from the Sun.
This year, 2022, spring equinox happens at precisely 9:33 a.m. MT on March 20.
The spring equinox always occurs on March 19, 20, or 21, however, we won’t see another March 21 equinox until 2101 (the last was in 2007).
Spring is nature’s renewal season, and many cultures celebrate the occasion, with holidays like Easter and Passover.
Here are some things that happen in spring:
- Worms and grubs reappear
- Birds migrate northward
- Days get longer (which also causes birds to sing more)
- Trees, shrubs, and flowers reappear
- Sun gets stronger
- Gardening begins
Many ancient sites mark the equinoxes as well, with one of the most famous being the Chichen Itza in Mexico, built by the Mayans in A.D. 1000.
Today, the way the Sun’s light falls on the pyramid signals the beginning of seasons.
On the spring equinox, the light will reflect in a way that a huge snake appears to be slithering down the steps. The Mayans called this day “the return of the Sun serpent.”