Autumn Equinox 2024 Southern Hemisphere Calendar. 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. In the northern hemisphere, it represents the beginning of autumn, while in the southern hemisphere, it marks the beginning of spring.
When does the autumn equinox. In 2024, the autumnal equinox will take place on september 22,at 08:44 a.m.