In recent years, I remember the sheer excitement of experiencing a total solar eclipse. For a few minutes seen from any one vantage point, the moon stood between me and the sun, covering its bright disc with just a fiery corona visible around the edge. Cool!
Solar eclipses are actually common. There are a handful of partial solar eclipses every year, and a total eclipse every eighteen months or so. That said, they are relatively uncommon from any one location on the planet. Total solar eclipses are only seen every four centuries from any single place on the Earth’s surface. So, for most of us, eclipses are exciting and dramatic events.
Some ancient civilizations regarded eclipses as evil omens predicting a calamity, such as the death of a king. They thought that eclipses were unnatural, a sign that something was broken and about to result in dire consequences. We know now just how natural these events are. But have you ever considered just how remarkable they are anyway?
Think about this. In an eclipse, the disc of the moon in the sky covers almost exactly the disc of the sun. If you knew nothing about space objects, you could reasonably assume that the sun and the moon were the same physical size. But of course they are not. The sun is huge, about four hundred times the diameter of the moon. The difference? Distance. The sun is almost four hundred times as far from us as the moon is.
Here’s the amazing thing. We would not be able to enjoy solar eclipses the way we do today (where the moon’s disc just covers the sun’s disc) if those sizes and distances were different. If Earth were further out, say, where Mars orbits, the sun would look tinier, and the moon would block it entirely. Move us inward to the orbit of Venus and the moon would be too small to cover the sun’s giant orb. Put it another way: these numbers seem “tuned” to allow the sun and moon to appear the same size. Quite a trick! But what do we make of it?
Now, if you are of one frame of mind, you’d say, “Well, what a cool coincidence!” If you’re like me, though, you might say, “Wow, it looks carefully adjusted; that suggests a Cosmic Adjuster.” As a one-off, perhaps it’s no big deal, just one of those odd flukes. But once you start finding other instances of precise adjustment in nature, it’s fair to ask whether life on Earth is as random as we were all taught as kids. There just might be a hand on the dial after all.
One final thought. Eclipses are quite predictable. Ancient civilizations were pretty good at it, and the guys that built Stonehenge used those pillars to predict eclipses. Since Newton’s time, we’ve gotten better because we understand orbital mechanics. Stars, planets, and other celestial bodies follow predictable pathways. It’s like a big, intricate clock, and all it takes is math — well, OK, pretty serious math — to guess which way the hands will point. That alone is awe-inspiring and suggests that all this symmetry is not accidental.
So, next time you don your safety shades and watch the moon slowly make the sun disappear, like a planetary magic trick with coins, you might ask yourself how that trick is done — and if there just might be a skilled master behind the curtain.