Jens was 60 when he started constructing the clock, but the story starts when he was only 25. In Strasbourg, the young locksmith saw an astronomical clock with a perpetual calendar in a cathedral.

The astrological clock’s digital components were built in the Czech Republic by the SPEL Company in Prague, caretaker of the 15th century Prague Orloj, built in 1410.

Auctions A Towering 18th-Century Astronomical Clock, Made by a Clockmaker to King Louis XV, Could Fetch $850,000 at Auction The clock still works, even after two and a half centuries.

This is an astronomical clock made by Song I-yeong, who was an astronomy professor in 1669 during the reign of King Hyeonjong of Joseon. The diameter of the clock is 40 centimeters (15.74 inches ...

CEDAR RAPIDS — Some clocks just go “tick tock.” A few do astronomical things. By fall, the Clock Tower standing silently in Czech Village will sing and dance, and show the phases of the sun ...

The clock, updated 70 years ago, is outdated once again. Rather than reminding onlookers of the virtues of a living, breathing regime, its face acts more as a gravestone, commemorating a long ...

The Astronomical Clock’s mechanical elements are driven by a single stepper motor, and the only gear is the one that interfaces the motor shaft to the rest of the device.

Many astronomical clocks, such as the famous clock in Prague, also use an astrolabe-style display that uses a stereographic projection of the ecliptic plane.

These clocks often fall out of synch, with astronomical time falling behind atomic time, but this has been rectified "by the insertion of leap seconds ", by pausing the atomic clock.