September 23 is the autumnal equinox and the first day of fall. Celebrate the new season with these memes about all things fall like leaves changing color and pumpkins. There are two equinoxes every year, first the vernal (or spring) equinox around March 20, and second the autumnal equinox around September 22. They are seasonal points on the sun's path.The word equinox derives its name from Latin aequus nox, meaning "equal night," because during an equinox, daytime and nighttime are of approximately equal length. Click on for more information about the first day of fall and funny memes.