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Ursa Major (The Big Bear) and Ursa Minor (The Little Bear)

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How do you find the North Star?

If you can find the Big Dipper, you can point to the Polaris using the two stars in the bucket opposite to the handle of the Big Dipper.



Ursa Major (The Big Bear) and Ursa Minor (The Little Bear)

The Big Bear was actually a beautiful nymph named Callisto. Callisto was turned into a bear by Zeus to protect her from his jealous wife Hera. One day, Callisto ran into her son Arcas who was hunting in the woods. Arcas raised his spear towards the bear, his mother. Zeus, watching from above, acted quickly to save his beloved Callisto. He turned Arcas into a bear and hoisted them both into the sky by their tails. In doing so, Zeus stretched the bears' tails and they now appear that way in the sky.

The legends of some Canadian First Nations, including the Micmac and Iroquois, also identify this constellation as a bear. Amazingly, people from different parts of the world looked at this same patch of sky and perceived the same animal. Ursa Major includes the Big Dipper (known as "The Plough" in England). The Big Dipper's handle is the bear's tail, while its scoop is the bear's side.

The second star from the end of the Big Dipper's handle is really two stars, known as Mizar (the Horse) and Alcor (the Rider). In some cultures, these stars were once used as a way to test eyesight - if you could see the two distinct stars, you had great eyesight!

Five of the seven bright stars in the Big Dipper are part of a star cluster, meaning they were born at the same time and place in space and are roughly the same distance away from the Earth.


At the end of the Little Dipper, Ursa Minor, is our pole star, Polaris. Polaris, also know as the North Star, is about 50 times larger than our Sun, but it appears very faint as it is 600 light years away. Because Polaris is due North, it was a very important directional indicator for early navigators.

The entire sky appears to rotate around Polaris. If you extended the axis of the Earth's rotation up into the stars, it would point to Polaris. This means the North Star appears stationary from our point of view on Earth. All the other stars appear to rotate around Polaris.

The closeness of Polaris to Earth's axis of rotation is purely coincidental. There is no similar bright star near Earth's south pole. As well, the axis of Earth's rotation gradually swings around the sky every 26,000 years, like a top that is wobbling. A few thousand years ago Polaris was much farther from the North pole than it is now, and in a few thousand years it will be far away again.

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