Fall Equinox 🌗2018

Fall Equinox 🌗2018

🌞 🌗 🌞

Not as 'equal' as you may think

(CNN) — Twice a year, everyone on Earth is seemingly on equal footing -- at least when it comes to the distribution of daytime and nighttime.
Come Saturday, we'll enter our second equinox of 2018. If you reside in the Northern Hemisphere, you know it as the fall equinox (or autumnal equinox). For people south of the equator, this equinox actually signals the coming of spring.
Folks right along the equator have roughly 12-hour days and 12-hour nights all year long, so they won't really notice a thing on September 22.
People close to the poles, in destinations such as Alaska, go through wild swings in the day/night ratio each year. They have long, dark winters and summers where night barely intrudes.
But during the equinox, everyone from pole to pole gets to enjoy a 12/12 split of day and night. Well, there's just one rub -- it isn't as perfectly "equal" as you may have thought.
There's a good explanation (SCIENCE!) for why you don't get precisely 12 hours of daylight on the equinox. More on that farther down in the article.
Here are the answers to some of your fall equinox questions:
Where does the word 'equinox' come from?
From our CNN Fast Facts file: The term equinox comes from the Latin word equinoxium, meaning "equality between day and night."
When is it?
In 2018, it falls on Saturday, September 22. There's actually a precise time for it: 1:54 UTC. (The UTC stands for Coordinated Universal Time.)
That time converts to 9:54 p.m. ET in the United States. Here's a handy online tool to convert UTC to your local time.
Why does fall equinox happen?
The Earth rotates along an imaginary line that runs from North Pole to South Pole. It's called the axis, and this rotation is what gives us day and night.
However, the axis tilts at 23.5 degrees, as NASA explains. That positions one hemisphere of the planet to get more sunlight than the other for half of the year's orbit around the sun. This discrepancy in sunlight is what triggers the seasons.
The effect is at its maximum in late June and late December. Those are the solstices, and they have the most extreme differences between day and night, especially near the poles. (That's why it stays light for so long each day during the summer in places such as Scandinavia.)
Since the summer solstice in June, days have been progressively becoming shorter in the Northern Hemisphere and the nights longer for the past three months. Welcome to fall equinox!

https://www.cnn.com/travel/article/fall-equinox/index.html