An astrolabe is an ancient instrument used for solving problems related to time and the position of celestial bodies. It consists of a flat disk with a rotating arm, called an alidade, which helps users measure angles in the sky. Astrolabes were widely used by astronomers, navigators, and astrologers in various cultures, including the Islamic Golden Age and Ancient Greece. These devices can determine the altitude of stars and planets, making them useful for navigation and timekeeping. Astrolabes also played a significant role in the development of trigonometry and astronomy, influencing later tools like the sextant and the modern compass.