Changing trends in weather and fashion, the first day of spring is Sunday, March 20, starting at 8:33 a.m.
But what happens on a planetary level on the first day of spring?
The vernal equinox, or spring equinox, occurs when the Earth's tilt and orbit around the sun align its axis neither away from nor toward the sun. This date usually falls around the end of March.
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When this occurs, the sun shines directly on the Earth's equator. This means the length of day and night will be the same in both the Southern and Northern hemispheres.
In Latin, the word "equinox" actually means "equal night," composed of the roots "aequus," meaning equal, and "nox," meaning night.
This phenomenon also occurs during the autumnal equinox in the fall during the month of September.
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One equinox, two changes of season
While an equinox grants both hemispheres equal lengths of day and night, this event heralds opposing seasons for those north and south of the equator.
In the Northern Hemisphere, this equinox brings blooming spring flowers and warm temperatures.
Meanwhile, the Southern Hemisphere sees falling leaves and chillier days as it transitions into fall.
Longer days ahead
The vernal equinox also means the days will get shorter for those in the south and longer for those in the north.
Those up north can expect to see the days get longer until June 21 when summer begins.