Astronomical clocks

clock with special mechanisms and dials to display astronomical information

thumb|The astrarium made by Giovanni Dondi dell'Orologio showed hour, year calendar, movement of the planets, Sun and Moon. Reconstruction, [[Museo Nazionale Scienza e Tecnologia Leonardo da Vinci, Milan.]]

A tellurion (also spelled tellurian, tellurium, and yet another name is loxocosm), is a clock, typically of French or Swiss origin, surmounted by a mechanism that depicts how day, night, and the seasons are caused by the rotation and orientation of Earth on its axis and its orbit around the Sun. The clock normally also displays the phase of the Moon and the four-year (perpetual) calendar.

fortified clock tower in Lier, Belgium

advanced astronomical clock

type of structure attached to a mosque

15th-century astronomical clock in Lund Cathedral