Equinox Myth

Published: March 20, 2021, 5 a.m.

Today is the vernal equinox — the beginning of spring in the northern hemisphere. It comes with a persistent myth: that you can balance an egg on its end on the equinoxes — and only on the equinoxes.

Like most pseudoscience, the myth invokes a few scientific terms to make it sound reasonable. Unfortunately, though, throwing in words like “equinox” and “gravity” doesn’t cleanse the smell of rotten eggs.

Here’s the basic outline of the tale: At the equinox, the Sun stands directly above the equator at noon. That part is true. So there’s a special gravitational “balance” that doesn’t exist at other times of the year. That part isn’t true. This balance allows you to stand a raw egg on its end, which can’t be done on any other date. And that part is absolutely rotten.

It may well be true that more eggs are balanced on end on the March equinox than at any other time of year. If so, it’s only because more people give it a try then.

It’s easy to disprove this tale by trying to stand an egg on end on different days of the year. It’s not easy at any time; the egg’s interior is a thick liquid, so it doesn’t want to sit still. But with a little patience it can be done. It’s easier to accomplish if the egg has a rough shell and it’s sitting on a rough surface. But many people have done it with smooth eggs on glassy surfaces. Just keep trying, and eventually you’ll get the egg-xact formula — no matter what the date.


Script by Damond Benningfield

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