An armillary sphere is a model of objects in the sky, consisting of a spherical framework of rings, centred on Earth or the Sun, that represent lines of celestial longitude and latitude and other astronomically important features, such as the ecliptic.

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An astrolabe is an astronomical instrument dating to ancient times. It serves as a star chart and physical model of visible heavenly bodies. Its various functions also make it an elaborate inclinometer and an analogue calculation device capable of working out several problems in astronomy.

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The first astronomical clocks were built in the 13th century. Special mechanisms and dials were used to display astronomical information such as the relative positions of the sun, moon, zodiacal constellations, and sometimes major planets. 

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An orrery is a mechanical model of the Solar System that illustrates or predicts the relative positions and motions of the planets and moons, usually according to the heliocentric model.

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Celestial spheres were used in navigation and became popular for long expeditions overseas. We can find engraved copper spheres from the period following the discovery of the New World until the 18th century. Celestial objects fixed to the inside of a sphere helped to situate and predict star positions in the sky.

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