Big Dipper And Cassiopeia Harmonize At Dusk

The Big Dipper, part of the larger constellation Ursa Major the Great Bear, and Cassiopeia the Queen hang in balance at the end of evening twilight around 9 p.m. local time on September 3. Stellarium

Many of us strive for some sort of balance in our lives. I try all the time and succeed every once in a while. I might get a few hours’ worth of harmony before this or that anxiety returns. If pain is essential to experiencing joy, harmony requires disfunction. We can seek balance in the stars too, a fine example of which is on display at dusk in the northern sky this week.

Look to the northwest to find the Big Dipper, which forms the tail and hindquarters of the Great Bear. The familiar figure is just now easing down toward the northwestern horizon in sync with the time bears begin to hibernate. For many skywatchers, the bear remains low in the trees or mountaintops — or even hidden below the horizon for the Deep South — from mid-fall through early winter.

I get a little wistful seeing the Dipper drop, but as long as the Earth keeps circling the sun, the bear will rise again and again. As with all things in the night sky, as one constellation moves out of the picture, another takes its place in the spotlight. Tonight, look on the opposite side of the North Star from the Big Dipper to find the “W” of Cassiopeia ascending in the northeast. In June and July it made itself scarce, hovering above the northern horizon and often hidden by hills and trees, but in November the W will blaze from high in the northern sky.

Right now, the W and the Dipper lie at about the same altitude above the horizon on either side of Polaris at nightfall around 9 p.m. in early September. They’re neatly balanced in a sort of constellation harmony, the same way two children at opposite ends of a seesaw hold to level for a few thrilling moments before shifting weight and heading in opposite directions. But symmetry is easily broken; by 10 o’clock they’ll be out of alignment.

The Big Dipper and Cassiopeia one month from now on Oct. 3 at 9 p.m. Stellarium

The pleasant symmetry repeats at 9 a.m. tomorrow morning in a blue, sun-shot sky — but with the Dipper and W on opposite sides of Polaris — and again that night around 8:56 p.m. Four minutes sooner? Yes, because the Earth has moved about 1,598,400 miles in its orbit around the sun from the previous day. That distance, only a tiny slice of the 583,000,000 miles we travel around the sun each year, is enough to make the stars shift slightly to the west. These shifts accumulate night after night, causing the constellations to cycle around the entire sky over the course of a year.

Tiny things can restore our own sense of balance. It might be plucking a ripe tomato from your garden, getting a hug from a friend or family member or doing someone a favor. More than anything, harmony’s a matter of being awake and paying attention. Look north tonight and learn.