September 23 is the Fall Equinox…

…When the sun, in its tropic to tropic cycle, is on the equator.

Its the “fall” equinox because the sun is moving downward, and outward from the tropic of cancer,
and toward the tropic of Capricorn…The sun is moving down, closer to the earth.

…Thus the sun is “falling.”

My whole Analemma series is Here.