Richard Lange Perpetual Calendar Terreluna watch is much more than a traditional perpetual calendar. Turn it over and you will see one of the most complicated and unconventional moon-phase displays ever made. In the center is a disk bearing a map of the Northern Hemisphere. Surrounding the earth is a disk decorated with 2,116 stars.
The earth disk rotates counterclockwise once every 24 hours; you can see the time anywhere in the world by referring to the 24 hour markers on the ring surrounding the display. The moon orbits the earth once every synodic month, i.e., once every 29 days, 12 hours, 44 minutes and 3 seconds.
As the moon orbits, it waxes and wanes. The watch’s balance, visible through the caseback, represents the sun: when the moon is between the earth and the balance, the moon disk is all blue, representing the new moon. The moon display is so accurate that it will be 1,058 years before it needs to be corrected by one day.
The day, date, and month are shown in apertures.On the front of the watch is a regulator-style dial with minutes in the large circle and hours and seconds in the two smaller circles. The watch has twin barrels that provide a power reserve of 14 days; the power- reserve indicator is at 6 o’clock.
A. Lange & Söhne not only famous for its high quality,but also for its chic appearance.For hundred years,it is a leader of watch.