Oh, Polaris

A few nights ago, there was break in the clouds big enough for me to go out and look up at something other than flat grey for a little while, though, that’s not without its own merit. Taurus and Orion were rising over the houses across the street, so I brought my binoculars out to have a look at the Pleiades, again. It’ll be a sad day for me if I ever get tired of looking at them. While I was out there, a neighbor came by and asked if I was checking out the north star. When I told him it wasn’t and pointed in Polaris’s direction, he asked if I was sure, because what I was looking at was so bright.

This, mistaking some very bright object for Polaris, is pretty common. The star we were pointing at was Aldeberan, the orange giant star in Taurus. It’s certainly a conspicuous enough one, the 14th brightest in the night sky, and one of the two or three brightest in that neighborhood. Polaris on the other hand, appears much dimmer from here on Earth; it’s only the 49th brightest in the nighttime sky. From where we stood, it’s a pretty unremarkable star. This isn’t really true, though. It’s actually a multiple star system with a yellow giant, and all kinds of other excitement, but its place as the north star, as the ages-old beacon for navigators in the northern half of the world, certainly brightens its fame.

Polaris is the brightest star in the Little Dipper, which is really Ursa Minor. Finding that constellation is always a challenge for me. I live in the suburbs in the northeast of the United States, so there’s never enough darkness. I can’t say for sure that I’ve ever actually seen the Little Dipper, no matter how many charts and mnemonic devices I use. It’s just too small and too faint. Fortunately, I’m not often lost at sea, so I don’t really ever need to see it. It’s always nice, though, just like being able to pull a quarter from a surprised kid’s ear, to be able to turn around, pick out a star, and say “That’s Polaris; that’s the north star.” It’s a great party trick.

As it turns out, even though you might not be able to find its constellation, there are two other easy-to-find asterisms nearby, which can help you. Ursa Minor is right between the Ursa Major and Cassiopeia. Everyone recognizes the Big Dipper, so Ursa Major is easy to find. Cassiopeia is the 3 or W (or M, or E)-shaped group of stars not far away. Polaris is smack in the middle between the two, in an area where even its dimness is the brightest thing around.

Have a look at the screenshot below, from Stellarium. That’s the sky over my house at around 10:30 tonight. I left everything unlabeled, but you should be able to see Cassiopeia up to the left and the Big Dipper over to the right. The crosshairs are on Polaris. Night after night, season after season, year after year, the two dance and spin around each other, so you might have to orient yourself a little, but Polaris is always right in the middle. So, if you can find it, great. If not, you can pretty easily guess where it’ll be, and surprise your friends, or find your way home.

2015-12-16 16_48_06-Stellarium 0.12.4
The skies to the north, with Polaris highlighted
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