Lunar cycle lasts 29 days, 12 hours, 44 minutes, 2.8 seconds.
Drawing their inspiration from the clear night skies of the Vallée de Joux, generations of Audemars Piguet watchmakers have crafted prestigious timepieces capturing the astronomical cycles of days, months, years and the phases of the moon. Today, to complete these indications, some perpetual calendars also offer the practical function of displaying the week.
A perpetual calendar is endowed with a mechanical memory which maps time cycles of 48 months. It automatically factors the varying number of days per each month (30 or 31), while adjusting the number of days in February, whether 28 or 29, during leap years. This complicated mechanism only needs manual adjustment every 100 years!
The number of parts in calibre 5133, whose perpetual calendar functions are rearranged on one single level.
The number of parts in calibre 5134.
The perpetual calendar will not require any adjusting before 2100.