Today’s Google Doodle celebrates the colors of Fall with an animated image showing a figure walking along a line of trees. As the figure passes, the trees each change colors from shades of grey to shades of red and gold before falling off to reveal the Google name spelled by the trees’ bare branches. A single leaf remains for a second longer before drifting down to rest on the head of the figure.
Metro states, “Equinox, from the Latin for ‘equal night’, occurs when the Earth’s axis tilts neither towards nor away from the Sun, making day and night of roughly equal length – though not exactly.”
According to a list on Wikipedia, the equinox for both March and September have important cultural significance in addition to seasonal weather changes and hours of daylight vs night. Some examples include Mabon, a pagan festival of thanksgiving for the fruits of the earth and a recognition of the need to share them to secure the blessings of the Goddess and the God during the coming winter months, for the Northern hemisphere, and Ostara, inaugurating the new year on the Zodiacal calendar, as well as the time of rebirth or return for vegetation gods and a time of great fertility for the Southern hemisphere.