Celestial Secrets from Vacheron Constantin

Vacheron Constantin has chosen its quarter-millennium year to revisit one of the most audacious ideas in watchmaking.

The Les Cabinotiers Celestia Astronomical Grand Complication returns as two unique pieces, Homage to Ptolemy and Homage to Copernicus, each a double-sided wristwatch that translates ancient cosmology into contemporary haute horlogerie.

Both are driven by Calibre 3600, a movement five years in development, only 8.7 millimetres thick, and composed of 514 components that orchestrate twenty-three astronomical indications. The pair introduces a new Les Cabinotiers series to celebrate the Maison’s 270th anniversary.

A choice of universe

The narrative begins with the thinkers who first sought to describe the sky. One watch nods to Ptolemy and the Earth-centred model of the cosmos, while the other honours Copernicus and the solar revolution.

Vacheron Constantin expresses these visions not only through dial printing but also through sculpture in precious metals.

The cases are engraved with the orbital architecture of each theory so that the planets trace their paths around either the Earth or the Sun. Here, the case tells the story as eloquently as the movement within.

Three readings of time

Celestia lives up to its name by offering civil time, solar time, and sidereal time, each with its own dedicated gear train. The front dial sets civil time against a running equation of time so the sun-tipped minute hand will hurry or hesitate through the seasons as nature dictates.

The differential ranges from sixteen minutes slow to fourteen minutes fast across the year and aligns on only four days. A shaped cam translates celestial mechanics into a daily display that needs no interpretation.

Turn the watch over and the stars take command. A rotating celestial map, made from two sapphire discs, presents sidereal time, which gains approximately four minutes on civil time each day.

A blue ellipse shows which constellations are visible from a given latitude at that moment, while the celestial equator and the ecliptic are traced for reference. It is a private planetarium that rewards quiet study.

A calendar for connoisseurs

The front is a masterclass in legible density. A perpetual calendar displays day and month in apertures with a serpentine date and a leap year indicator, correctly set until the year 2100.

The precision moon phase requires a single day of correction every one hundred and twenty-two years, and the age of the moon is read at its edge. Sunrise and sunset occupy graduated arcs at six, while a gauge between them charts the length of day and night. A seasonal disc carries the zodiac, the solstices, and the equinoxes.

At eleven sits a mareoscope, a tide display that pairs a tidal level indication with a three-dimensional reading of Earth, Moon, and Sun alignment to explain spring and neap tides at a glance. It is functional poetry that makes a wealth of information feel calm.

The reverse with tourbillon and stamina

On the back, the sidereal display shares space with a peripheral power reserve that reads three weeks, delivered by six barrels in series.

The one-minute tourbillon appears here rather than on the front, a deliberate decision to keep the astronomical tableau uncluttered.

Its cage adopts the Maltese cross that has marked Vacheron Constantin since the nineteenth century and provides a quiet counterpoint to the animated sky.

Métiers d’art that speak in relief

If the dials are scholarship, the cases are sculpture. The Ptolemaic model in white gold is a lesson in geometric discipline. The engraver set out planetary ellipses that remain continuous across lugs, bezel, and caseband.

Using the champlevé technique, the ground is hollowed to fractions of a millimetre and chased to a fine matte while the orbital rings are polished in relief. The planets are subtly domed, and the continents of Earth are hand-polished.

The Copernican model in 5N pink gold presents a different challenge. Because the orbits are offset to the left, their centres fall beyond the case itself, which required custom tooling to trace the arcs across a curved surface.

Here, the crown becomes the Sun, and the planetary relief is polished against a textured field. Each case consumes in the region of two hundred and forty hours at the bench, a figure that feels plausible the moment you run a fingertip along the engraving.

The particulars

Both watches are single-piece creations bearing the Hallmark of Geneva and share a double-sided case that measures forty-five millimetres in diameter and 13.91 millimetres in height with water testing to three bar.

The Homage to Ptolemy reference is in hand-engraved white gold with a grained white gold dial. The Homage to Copernicus is in 5N pink gold with a matching dial. Each is delivered on dark blue Mississippiensis alligator leather with a hand-engraved folding clasp in the case metal.

Movement connoisseurs will note the steady 2.5 hertz beat rate, a nod to classical chronometry as much as a practical choice for long autonomy.

Why it matters

Celestia first appeared in 2017 as a consolidation of everything Vacheron Constantin knew about astronomical watchmaking. It followed the record-setting reference 57260 and went on to win the Mechanical Exception prize at the Grand Prix d’Horlogerie de Genève in the same year.

Its return as two unique pieces is not an exercise in nostalgia. It is a reminder that a great calibre deserves fresh narratives and that ideas from astronomy can still feel new when expressed with craft. In an era of instant novelty, this is slow time done with conviction.

For the seasoned collector

These pieces sit at the intersection of scientific instrument and wearable art. They invite a morning reading of the seasons and an evening check of the stars.

They also demonstrate how a maison can use an anniversary to speak about identity rather than age. The message is clear. Excellence is a quest that spans centuries, and the sky remains a worthy guide.