Prague astronomical clock
The Prague astronomical clock or Prague Orloj is a medieval astronomical clock attached to the Old Town Hall in Prague, the capital of the Czech Republic.
Prague astronomical clock
The clock tower
Astronomical dial
The Moon sphere is seen showing approximately a quarter moon
An astronomical clock, horologium, or orloj is a clock with special mechanisms and dials to display astronomical information, such as the relative positions of the Sun, Moon, zodiacal constellations, and sometimes major planets.
Face of the Prague astronomical clock, in Old Town Square
The astrarium made by the Italian astronomer and physician Giovanni Dondi dell'Orologio showed the hour, the yearly calendar, and the movement of the planets, Sun and Moon. Modern reconstruction in the Museo Nazionale Scienza e Tecnologia Leonardo da Vinci, Milan, Italy; it is about three feet high.
The courtier and bibliophile Louis de Gruuthuse in front of an astronomical clock. Henri Suso, Horloge de Sapience, 1470-1480
The Rasmus Sørnes Clock.