All Things Being Equal

September is one of those transitional months. School–aged kids know instinctively what fall means, and now many Michigan adults find themselves school bound for work related retraining. Even at work the feeling can change; no more “sliding out” early on Friday afternoon to find a favorite beach or an empty picnic table. There’s a palpable crispness in the air, a curt bustle in our motions, as if we still had to gather in the crops before the first hard frost.

The equinox approaches. Day submits to the creeping onslaught of night. Practically speaking, we have to walk the dog before it gets dark. We don’t linger outside talking to neighbors as late. The balance of power between light and dark is coming to equilibrium. We could relax in the abatement of burning rays from the sun and enjoy the lessening humidity and moderate temperatures, but we know what comes next: the utter and complete domination of a Michigan Winter. Can you hear the distant bells tolling for our dying summer?

Equilibrium of night and day means that the stars appear earlier. You don’t have to stay up very late to see the mighty planet Jupiter hovering low in the western twilight sky, or to see Princess Andromeda and her hero Perseus playing out their ancient story in the deepening night. So let’s quell those morose tolling bells and enjoy the equinox, for it brings some of the most interesting constellations and the biggest of planets to the early evening sky. Plus, fall in temperate Michigan is nothing to sneeze at! (Unless you suffer from allergies as many of us do!)

I like to think of autumn “advancing” because that word reflects what’s happening in the sky. The Sun, positioned against a background of very distant stars, seems to be marching eastward little by little. We can’t see this happening because the blue day sky prevents us from seeing the stars and the sun at the same time. The only change we can detect is the advancing of sunset, minutes earlier each day. If we could watch the process from space, we would see our home planet plodding along its normal course around the sun.

One result of this plodding motion is that the constellations that have been with us all summer are now getting lost in the glow of the sun. It also means that the star patterns that you’ve seen in the sultry summer mornings are now visible much earlier in the evening. Instead of the Summer Triangle adorning the sky all night, it will be fading not long after sunset. And the glorious and familiar constellations of fall, our friends Perseus and Andromeda, Cassiopeia and Pegasus, have migrated from early morning apparitions to familiar players in our evening heavenly tableau.

All things being equal, we can enjoy the moderate temperatures, the early evening sunsets, and the convenient timing of the crisp and clear fall night sky. The equinox occurs on September 23rd, the day when the sun rises due east, sets due west, lingers in the sky for half of the earth’s rotation, and goes down in time for us to take a break from the bustle of fall and enjoy the twinkle of the celestial bodies in the autumn sky.

Until next week, my friends, enjoy the view.