Watch of the Month - Audemars Piguet Equation of Time

The Audemars Piguet Jules Audemars Equation of Time watch is a handsome timepiece with a classic design and unique complications. The round case is in 18k yellow gold and comes on a black alligator strap with a gold “AP” design deployment clasp. This model is the San Juan Puerto Rico edition. The watch has an automatic movement displayed under the sapphire glass caseback. Functions include subseconds, date, day, month, moonphase, Equation of time and perpetual calendar.

The equation of time indicator (the hand with the sun emblem) points to markings on the bezel ranging between +15 to -15. For simplicity we have defined a day to be exactly 24 hours in length. In reality, though, the defined 24-hour day is an average, it does not correspond exactly to the actual length of a solar day. Because earth’s orbit is elliptical, the actual solar day may be up to 15 minutes longer or shorter, depending on the time of year, than 24 hours. This difference between the length of the actual solar day, and the 24-hour day, is called the equation of time.

With Audemars Piguet winding box. Ref 25934BA/O/6601CR/01.