Autumn Equinox: What Makes this Phenomenon Phenomenal 

As summertime ends, fall begins. That may mean pumpkins, turkey, and football, but have you ever wondered why we have a fall season in the first place? Let’s look at the stars and find out the beauty behind what makes fall, fall: the autumn equinox. 

How the Autumn Equinox was Discovered

The Autumn Equinox dates back to Ancient Greece when Hipparchus noticed locations of the stars relative to Earth, according to SciHiBlog.com. The stars would rise and fall each day relative to Earth’s location. With this knowledge, Hipparchus concluded that there are periods in which days and nights are the same length. That conclusion was later labeled an equinox. 

History.com says the word equinox comes from the Latin words “aequi,” meaning equal, and “nox,” meaning night.  Due to a lack of clocks, the sun’s position in the sky indicated the time for many ancient civilizations. The autumn equinox was seen to them as a time of worship to their respective god(s) and beliefs. Ancient Greeks believed goddess Persephone would return to the underworld with her husband, Hades. Some Japanese Buddhists celebrate Higan, a return to their hometowns to honor their ancestors. Modern Pagans celebrate Mabon, a harvest festival celebrating Earth and her gifts. 

What it Means

Given its Latin translation to “equal night,” an equinox is a moment when the length of the day and the night are equal. In astronomical terms, an equinox is when the sun passes the celestial equator – an extension of Earth’s equator into space – and moves from the Northern Hemisphere to the Southern Hemisphere, or vice versa for the spring equinox. Remember that while the Northern Hemisphere is in fall, the Southern Hemisphere is in spring. Therefore, the Northern autumn equinox is the Southern spring equinox, and vice versa. 

For those living in the Northern Hemisphere, the autumnal equinox happens every year between September 21 and September 24, according to History.com. That means the sun will pass the celestial equator from the Northern Hemisphere to the Southern Hemisphere, making the days shorter and the nights longer as winter approaches. 

Autumn Equinox in Central Florida

The autumn equinox for the Northern Hemisphere falls on Saturday, September 23. No phenomenon in the sky happens when the sun passes in front of the celestial equator. Still, if you want to experience the autumn equinox, it occurs between 1:50 a.m. and 2:50 a.m. 

More Information

For more information about the autumn equinox, visit Almanac.com, Biograview.com,  Earthsky.org, FarmersAlmanac.com, History.com, and Study.com.