September Equinox 2019 will be at 3:50 AM on
Monday, September 23
All times are in Eastern Time.
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https://www.vox.com/science-and-health/2019/9/20/20874986/fall-equinox-2019-september-23The fall equinox is Monday: 9 things to know about the first day of autumn
A brief scientific guide to the first day of fall.By Brian Resnick@B_resnickbrian@vox.com Sep 20, 2019, 9:10am EDT
The autumnal equinox is upon us: On Monday, September 23, both the Northern and Southern hemispheres will experience an equal amount of daylight.
For those of us in the Northern Hemisphere, it marks the beginning of astronomical fall, with daylight hours continuing to shorten until the winter solstice in December. For those south of the equator, it’s the beginning of spring.
Technically speaking, the equinox occurs when the sun is directly in line with the equator. This will happen at 3:50 a.m. Eastern on Monday.
Below is a short scientific guide to the most equal night of the season.
1) Why do we have equinoxes?
The fall and spring equinoxes, the seasons, and the changing length of daylight hours throughout the year are all due to one fact: Earth spins on a tilted axis.
The tilt — possibly caused by a massive object hitting Earth billions of years ago — means that for half the year, the North Pole is pointed toward the sun (as in the picture below). For the other half of the year, the South Pole gets more light. It’s why we have seasons.
