3.2: The Big Dipper

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The Big Dipper consists of 7 bright stars, forming a dipper, a small pot with a long handle. In England it is often called “the plough” (spelled “plow” in the US), and fugitive slaves before the Civil War knew it as “the drinking gourd,” a signpost in the sky pointing the way north to safety, to Canada where slavery was outlawed. Astronomers name it “Ursa Major,” Latin for “the big she-bear,” and some other languages also refer to it as the Big Bear. In Greek, bear is “Arktos,” and hence the far-north region where this constellation is usually overhead became known as “the Arctic.”

When the territory of Alaska in 1926 decided to create a flag of its own, it asked citizens to submit proposed designs for the new flag. The winning design was that of Benny Benson, age 13, and is reproduced here (more about him --- see below). It shows the 7 stars of the Big Dipper and Polaris, the north star. When Alaska became a state, this became the state flag.

The flag also shows how the north star can be found. Imagine a line connecting the two stars at the front of the “dipper,” continue it on the side where the dipper is “open” to a distance 5 times that between the two stars (the flag shortens this a bit!), and you will arrive at (or very close to) the pole star. Because of their role in locating Polaris, these two stars are often called “the guides.” And by the way --- the last-but-one star in the handle of the “dipper,” named Mizar by Arab astronomers, is a double star, whose components are readily separated by binoculars --- or, some say, by very sharp eyes during good viewing conditions.