Why is it called the Spring Equinox?
Happy First Day of Spring!!! The Spring Equinox is upon us. My computer is also acting up, and moving pretty slowly, so I'm going to use it as an excuse to make this blog post short and sweet. The Spring Equinox happens on the 19th, 20th, or 21st of March each year In the Northern Hemisphere (It's Fall in the Southern Hemisphere). This year, Spring is extra special.
For much of the last century, the spring equinox has occurred on March 20th or 21st. This year, however, the equinox happens on the 19th in all U.S. time zones, making it the earliest spring we’ll have seen in our lives (so far). The last time spring arrived this early was in 1896... that's 124 years ago! Interestingly enough, due to time zone differences, there isn’t a March 21st equinox in mainland U.S. during the entire 21st century! We won’t see a March 21st equinox again until 2101!
Now, let's get to today's question, which stems from my curiosity regarding the Spring Equinox (March here in the Northern Hemisphere) and what exactly that means. In a nut shell, an equinox happens twice a year (Spring and Fall), when the tilt of the Earth's axis and the Earth's orbit around the sun combine in such a way that the axis is straight up and down, it's not tilted away nor toward the sun. This leads to the Southern and Northern hemispheres receiving the sun's rays equally.
Speaking of equally, Equinox comes from the Latin words aequi, which means "equal," and nox, which means "night. During the equinoxes the globe experiences about about equal day and night, rather than one hemisphere being darker for longer and one being lighter for longer like in the Winter and Summer.
If you'd like to really jump in to the nitty gritty, check out earthsky.org for some great (but also technical) explanations. There are also some great pictures and videos to help explain things a bit better. For now, I'll wish you a happy Spring and here's to new beginnings!