First Day Of Autumn 2024 Time And Date. The halfway points between solstices are the autumnal and vernal equinoxes. The first day of autumn often called fall (september equinox or autumnal equinox) is when the sun shines directly on the celestial equator passing from north to south and the length of day and night are almost the same.

As the warmth of summer gives. Most people on earth will experience around 12 hours of day and 12 hours of night during september’s equinox.