What is the relationship of the latitude of the observer and the altitude of polaris?

The altitude of Polaris, the North Star, closely corresponds to the latitude of the observer in the Northern Hemisphere. Specifically, if you measure the angle of Polaris above the horizon, that angle is equal to the observer's latitude. For example, at 40 degrees north latitude, Polaris will appear 40 degrees above the northern horizon. This relationship helps navigators and astronomers determine their latitude by observing Polaris.