An astrolabe was used for astrology, navigation and what else?
Astrolabe Muslim astronomer Albatenius in his treatise "Kitab az-Zij" (c. 920 AD), which was translated into Latin by Plato Tiburtinus ("De Motu Stellarum"). The earliest surviving astrolabe is dated AH 315 (927–28 AD). In the Islamic world, astrolabes were used to find the times of sunrise and the rising of fixed stars, to help schedule morning prayers (salat). In the 10th century, al-Sufi first described over 1,000 different uses of an astrolabe, in areas as diverse as astronomy, astrology, navigation, surveying, timekeeping, prayer, Salat, Qibla, etc. The spherical astrolabe was a variation of both the astrolabe and the armillary sphere, invented
Mariner's astrolabe Mariner's astrolabe The mariner's astrolabe, also called sea astrolabe, was an inclinometer used to determine the latitude of a ship at sea by measuring the sun's noon altitude (declination) or the meridian altitude of a star of known declination. Not an astrolabe proper, the mariner's astrolabe was rather a graduated circle with an alidade used to measure vertical angles. They were designed to allow for their use on boats in rough water and/or in heavy winds, which astrolabes are ill-equipped to handle. In the sixteenth century, the instrument was also called a ring. Many dates can be found for the