
I’ve heard it’s possible to balance an egg, or even a broom, on its end on the date of the equinox. There’s a good chance you’ve heard the same thing. It sounds incredible, but it’s true.
There’s nothing particularly extraordinary about that day though; it’s possible to balance an egg any day of the year. I balanced one on the dinner table today, July 5, just to be sure. You can try it too. It doesn’t require a supposed equalizing equilibrium of an equinox to make it happen, just a stable hand and a lot of patience! That rules out the popular misconception that an astronomical symmetry is what makes it possible to balance the egg.
An equinox happens twice a year when neither of Earth’s poles are tilted toward the Sun. The equinox marks the first day of spring or fall. The term equinox comes from Latin words meaning “equal” and “night.” On this date, day and night are supposed to be equal length, except they’re not. There’s an exception that I mentioned in this column recently; the atmosphere refracts the Sun’s apparent position upward by its own width when it’s at the horizon. As a result, we have more daytime than nighttime at the equinox. The actual equal day/night time can happen up to a week or more from the equinox date.
The autumnal equinox will happen September 22 of this year. This will be the beginning of the coldest half of the year. Thankfully, it won’t actually take up a full half year, though, before the vernal (spring) equinox arrives on June 20, 2022. The good thing about this is that, astronomically speaking, there’s no such thing as a long winter for the Northern hemisphere; they are all shorter than summer. It’s snow joke weather it seems like it or not! There are five fewer days during the winter “half” of the year.
Winters are shorter for us because the Earth moves faster around the Sun during the Northern hemisphere’s winter. The high speed results from the Earth being up to 2.5 million miles closer to the Sun during that time. So, it gets even better for us who are on top of the world. This closeness blesses us with a 7% increase of heat from the Sun when it’s closest during winter. Not that anyone notices it though; the Sun hangs so low on the southern horizon during winter that its extra heat isn’t felt very well.
There are two days of the year when we experience a solstice. These mark the official first day of summer and winter and are also the longest and shortest days of the year. On the summer solstice, the Sun is at its highest point at noon, causing the shortest shadows of the year. If you are at 23.5° north latitude at this time, your shadow is practically nonexistent. Objects like fence posts and buildings can look almost like they’re Photoshopped into the landscape since there are no shadows extending out from them. On the summer solstice, the Sun also rises and sets at its most northerly points, throwing light into your house at odd angles and lighting up the dust on those shelves you didn’t think needed cleaning.
Just as God decreed at creation, we still use the motions and positions of the celestial objects as a measurement “for seasons, and for days, and years” (Genesis 1:14).
