Object from: British Library on Flickr Commons.
Date: 901-1100 Place: Syria (Accession num: 1981-1380)
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Summary: An astrolabe (Greek: ἁστρολάβον astrolabon, "star-taker") is a historical astronomical instrument used by astronomers, navigators, and astrologers. Its many uses include locating and predicting the positions of the Sun, Moon, planets, and stars; determining local time given local latitude and vice-versa; surveying; triangulation; and to cast horoscopes. They were used in Classical Antiquity and through the Islamic Golden Age and the European Middle Ages and Renaissance for all these purposes. In the Islamic world, they were also used to calculate the Qibla and to find the times for Salah, prayers.
There is often confusion between the astrolabe and the mariner's astrolabe. While the astrolabe could be useful for determining latitude on land, it was an awkward instrument for use on the heaving deck of a ship or in wind. The mariner's astrolabe was developed to address these issues.
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