(Apologies to Southern Hemisphere readers! I’m writing about my personal knowledge of stargazing here, though I’d love to branch out more. Today we’re focusing on a northern constellation.)
Actually (let’s pretend I wear glasses so I can push them up at this point), the Big Dipper (or Plough, or Wagon, or Seven Great Sages) is considered an asterism in many Western cultures, which means it’s a subgroup of a larger constellation. The Dipper looks a little like a saddle on the back of the Great Bear (Ursa Major for you Latin speakers):
You can find several versions of the bear based on these stars, but I’ve connected the stars the way I’ve always liked best, because it doesn’t involve weird stick legs or an oddly long tail. The bear is sitting/lying down, facing left, with its head raised and one or two paws out in front.
The Dipper is perhaps best known for being closer to, and brighter than, the North Star itself. Polaris (our current North Star—read my post on how that’ll change over time) is dimmer in our sky than the stars of the Big Dipper, and it happens to be easily found by following the line drawn between the two stars at the front of the dipper’s bowl, Merak and Dubhe.
This obviously would have been incredibly useful for navigation in the absence of more exact methods, but it’s still good to know now, even though you can probably use your phone to find celestial north. Personally, my Luddite streak enjoys not needing to.
In addition to finding the North Star, the Dipper is useful for identifying other bright stars and can really help your casual stargazing game. Let me illustrate. (For your convenience, I’ve provided a literal illustration below the following metaphorical illustrations.)
From the arc of the Dipper’s handle, you can find Arcturus, in the constellation Bootes. Farther along in the same arc, you’ll find Spica (in Virgo). These two are easy to remember by reminding yourself to “arc to Arcturus, then speed on to Spica”.
In other directions, you can find a few other major stars. By following the line across the top two stars of the Dipper’s bowl, you’ll find Capella (in Auriga) to the right—think of going across the top or “cap” of the Dipper to Capella. If you trace down through the left stars of the bowl, you’ll get to Regulus (in Leo), reminding yourself that a leak from the Dipper will lead you to Leo.
These are just some examples of the stars and other objects you can find starting from the Big Dipper. As you can see, these four alone are enough to help you find four other constellations! For a list of these and other ways to use the Dipper to orient yourself in the sky, see here.
Stargazing is one of my favorite ways to bring my scientific knowledge into the realm of my everyday experience. You can enjoy it on a nighttime walk by yourself, on a camping trip with friends, at an event at your local museum or university…no special equipment needed! (If you want a little help from your phone, Sky Map is a cool app to check out.)
It’s a great activity for groups of any age, and gives you a reason to look up, which I think is overlooked and underrated as a way to appreciate our universe and get out of your own tired old thought patterns. Best of all, the stars in the Big Dipper are bright enough that they’re nearly always visible in a clear sky, even if you have some pretty strong light pollution. It’s hard to find a better place to start for stargazing than the Dipper.