When Is The Autumn Equinox 2025 Australia. Autumn equinox 2025 (beginning of astronomical autumn) on the day of the autumn (september) equinox, the sun, moving along the ecliptic, crosses the celestial equator, moving from the northern hemisphere to the southern. Fall equinox, harvest home, feast of avalon origins and significance:

So, that means that the 1st day of autumn in australia this year will officially be the 20th of march. The first day of autumn often called fall (september equinox or autumnal equinox) is when the.