DECATUR, Ill. (WAND) — Fall officially begins across the Northern Hemisphere on Sunday at 7:44 AM, while the Southern Hemisphere enters spring.
The autumn equinox means that the sun is directly over the equator and will continue to move south into the Southern Hemisphere towards the Tropic of Capricorn until the winter solstice in December.
Equinox is Latin for equal nights; however, the amount of daylight & nighttime is not equal during the equinox. This is due to the definitions of how sunrise & sunset are defined by observing the first disk of the sun rising & the last disk setting. Also, the refraction of light in the atmosphere affects how the sun is viewed compared to being crossed in the horizon.
Sunday's sunrise and sunset are 6:44 AM and 6:52 PM, which is 12 hours and 8 minutes. The equilux in Decatur occurs on Wednesday for exactly 12 hours (6:46 AM/6:46 PM). Daylight will continue to lessen during the fall months until the winter solstice.
However, the amount of daylight decreasing will decrease daily after the equinox. Also, we are losing more of our daylight through the evenings than the mornings since the range from the latest sunset to the earliest sunset is smaller (June 27th-December 7th) than the earliest sunrise to the latest sunrise (June 15th-January 4th).
