Landmarks in the Sky
Constellations make great landmarks for finding your way through the sky. But they can also help to find your way on the Earth. Long ago, stargazers recognized that the stars moved in predictable patterns. They also recognized that these patterns changed depending on the time of night, the time of year, and where on earth you looked at the sky. Everything changed except one star.
Pole Star
Polaris, or the Pole Star, lines up with the Earth's North Pole. Because of this, it works kind of like the flag at the top of a merry-go-round, or carousel.
In a carousel, all of the horses circle around the pole in the middle. A similar thing happens in the sky. All of the stars circle around Polaris through the night.
Little dipper
Polaris is part of a rather dim star pattern called the Little Dipper. Like the Big Dipper, the Little Dipper is also formed by a rectangle with a string of stars trailing behind. Polaris sits at the end of the Little Dipper’s handle. Polaris is not the brightest star in the sky, with a magnitude of nearly +2. But Polaris is easily the brightest star in the Little Dipper pattern.
The best way to find Polaris is to first find the Big Dipper, then imagine a line connecting the two corner stars that make up the front edge of the dipper’s bowl. Extend this line to about 5 times its size, and it will take you directly to Polaris. No matter what the Big Dipper’s orientation is in the sky, the front edge will always point towards Polaris. That’s why those two corner stars are called the Pointer Stars.