Having unveiled the world’s most complicated pocket watch with 57 complications (Ref: 57260) in 2015, it was only natural that Vacheron Constantin use all their learning from creating such a horological heavyweight on future timepieces. Well, they haven’t wasted any time and the result is the Les Cabinotiers Celestia Astronomical Grand Complication 3600, a unique twin-dial wristwatch with a whopping 23 complications.

The dial has a unique mareoscope displayEssentially astronomical complications appear on the front and back dials of the watch, providing a reading of time in three modes – civil, solar and sidereal – each driven by its own gear train. A unique piece, this watch represents five years of development and the undivided attention of a dedicated master watchmaker. What’s most remarkable about this timepiece is that these 23 complications are squeezed into a very wearable 45 mm white gold case that’s only 13.6 mm thick, a remarkable feat of miniaturization. 

Of the 23 complications, 15 are displayed on the front dial. Standard time is read off in the traditional manner courtesy of a pair of white gold open-tipped hands. Solar time is indicated by means of an additional coaxial pink gold minutes hand with a cut-out sun. This hand also serves a unique ‘running’ equation of time mechanism.

In a traditional equation of time display, a hand moves across an auxiliary scale running from +14 to -16, which tells you how much you need to add or subtract from the standard time to know the difference between the length of that particular solar day, and the mean, or average, solar day. In this instance, the continuously running pink gold minutes hand runs ahead or behind the traditional minute hand as the year goes by. 

It features a unique running equation of time. Since this is a unique piece for a specific collector, the front dial also displays sunrise and sunset times, pointed out by slim hands moving over two graduated scales, as well as the length of day and night appearing on a special gauge at 6 o’ clock. Another unusual complication is seen in a semi-circle at 4 o’ clock – zodiacal sings, seasons, solstices and equinoxes. 

In addition to the traditional moonphase and perpetual calendar display, the dial has a unique mareoscope – a remarkable display comprising a tide level indicator and a 3D depiction of the earth-moon-sun alignment. What is the significance of this indication? The position of the earth, moon and sun affects the height of the tides, which is also indicated here. 

The caseback has indications too.The second dial on the back of the watch has a celestial chart that depicts the constellations viewed from the Northern Hemisphere, ringed by an anthracite bezel ring showing the months of the year as well as a gauge-type power reserve indicator. A second disc rimmed by a graduated scale displays sidereal time, and one can also get a glimpse of the tourbillon at 6 o’ clock. 

The watch is powered by the one-off Caliber 3600, a handcranked movement composed of 514 components. This watch has an extraordinary three-week power reserve thanks to the use of a ductile Bioflex alloy mainspring. A total of six barrels connected in series power the three gear trains. The movement is only 8.7 mm thick and it also bears the Hallmark of Geneva seal. The timepiece is fitted with an alligator leather strap secured by a white gold pin buckle. 

This is no ordinary wristwatch. The Les Cabinotiers Celestia Astronomical Grand Complication 3600 is Vacheron Constantin at its best – a technical marvel that ticks the boxes when it comes to both aesthetics and wearability. 

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