At any given location in the northern hemisphere, the position of Polaris to the horizon can be calculated as an angle to formulate latitude. For example at the North Pole, Polaris is directly overhead giving a latitude of 90 degrees, while at the equator Polaris appears on the horizon with a latitude of 0 degrees.
Polaris has not always been the North Star, according to Earth Sky, with the position of stars changing over a period of centuries. Polaris is not the brightest star in the northern night sky, but the rest of the night sky does move around Polaris.
To calculate latitude, the equator around the center of the Earth is an equal distance from the North and South Poles. Lines of latitude are used to locate positions on the Earth's surface at an angle to the equator.
