Astrolabe

Astronomical instrument

An astrolabe (Ancient Greek: ἀστρολάβος, romanized: astrolábos, lit. 'star-taker'; Arabic: ٱلأَسْطُرلاب, romanized: al-Asṭurlāb; Persian: ستاره‌یاب, romanized: Setāreyāb) is an astronomical instrument dating to ancient times. It serves as a star chart and physical model of the visible half-dome of the sky. Its various functions also make it an elaborate inclinometer and an analog calculation device capable of working out several kinds of problems in astronomy.

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