Star navigation is a method used by sailors and explorers to determine their position and direction by observing celestial bodies, primarily stars. This technique relies on the predictable movements of stars and constellations, allowing navigators to use tools like the sextant to measure angles between stars and the horizon. Historically, star navigation was essential for long sea voyages before the advent of modern technology. Navigators would identify key stars, such as the North Star (Polaris), which indicates true north, helping them chart their course across vast oceans.