he numbers already speak for themselves: 7 years of development; over a metre high; 6,293 mechanical components, including 2,370 for the movement alone; 1,020 components for the habillage; 22 watchmaking complications; 144 mechanically programmed movements for the automaton via 158 cams; 2 musical themes and 15 patents, including 7 watchmaking patents.

Directed, much like a conductor leads an orchestra, by Vacheron Constantin, master artisans, designers, engineers, astronomers, a musician and, of course, master watchmakers worked together to bring this extraordinary project to fruition. Numerous métiers d’art contributed to its habillage and decoration, including gem-setting, hard-stone marquetry, mother-of-pearl marquetry, rock crystal inlay, Grand Feu enamel, guilloché, high-relief engraving, cast bronze sculpture and miniature painting on glass.

It is a complete work, intensely collaborative and immensely cultural, that sinks its roots in the curiosity mankind has always nurtured for the astronomical phenomena which underpin our ability to measure time; a work that draws on the scientific and technical advances of the Enlightenment – when Vacheron Constantin saw daylight, in 1755 –, but connects them to our present day; a work of mechanical artistry. All of which is justification for its name: La Quête du Temps.

Testament to Vacheron Constantin’s stated ambition to “go beyond watchmaking", this museum piece is, fittingly, shown in public for the first time as the centrepiece of an exhibition at the Louvre in Paris (September 17th to November 12th 2025), among historic timepieces from the celebrated museum’s collections. These include the La Création du Monde astronomical clock that was presented to Louis XV in 1754 and restored in 2016, with the support of Vacheron Constantin.

A human figure at the centre of time

At the pinnacle of La Quête du Temps stands the Astronomer, an intentionally androgynous, human figure with the poise and elegance of a dancer. As though at the centre of the universe, this Astronomer (almost 30cm tall) is surrounded by a glass dome that reproduces, in miniature painting, the constellations exactly as they would have appeared in the sky above Geneva on September 17th 1755 at ten in the morning, when Jean-Marc Vacheron signed the contract to employ his first apprentice. Their precise configuration was calculated by astronomers at Geneva Observatory (an institution which, among other achievements, was active in the discovery of the first exoplanet).

The Astronomer stands directly beneath a Sun, while a three-dimensional retrograde Moon passes in front of it, travelling along a semi-circular rail. On each side, seemingly floating in space, scales are marked for the hours, in Roman numerals, and for the minutes, in Arabic numerals. The Astronomer’s body, which was cast in bronze then gilded with 3N yellow gold, is engraved with the constellations, with diamonds representing the principal stars.

Remarkably – and an absolute first in horology – the Astronomer is not immobile. It is an extraordinarily complex automaton, capable of 144 smoothly flowing movements with which to indicate, by raising its arms, the 12 hours and the 12 five-minute intervals that make up each hour. To achieve this with the requisite precision, a mechanism comprising 158 cams links the Astronomer to the clock via a mechanical time memory.

Never before in the history of horology has an automaton indicated the time in space. Its creator, François Junod, is recognised as the most accomplished automaton-maker of his generation, yet he admits this was, by far, the most challenging project he has ever undertaken.

Compounding this difficulty, our astronomical dancer will perform, on demand, three choreographed sequences — and to music, thanks to the two “music machines” which François Junod invented and incorporated into the automaton’s mechanism.

In the first sequence, a melody “wakes” the Astronomer who takes in its surroundings before gesturing towards the day and night symbols at its feet. It then moves its hands to present the Moon and indicate its path along the arc in front of it, before returning to its original position. In the second sequence, to music composed by Woodkid and performed on a metallophone and Wah-Wah tubes, the Astronomer points to the stars above its head, first with its left arm, then its right arm, turning its head as it does.

For the third sequence, again on demand or programmable up to 24 hours in advance, the Astronomer indicates the time on the suspended scales. Adding a further level of complexity, the hours and five-minute intervals are marked in random order so that, even if the automaton is activated twice in quick succession, the gesture will be completely different each time.

All the Manufacture’s expertise in astronomical haute horlogerie

Under the automaton, the movement which Vacheron Constantin has developed specifically for La Quête du Temps is the distillation – one could say, the quintessence – of the Geneva Manufacture’s expertise in astronomical haute horlogerie. In addition to hours and minutes, it incorporates a complete perpetual calendar, indications of sunrise and sunset, a 15-day power reserve and sidereal time, on the reverse side. It also drives the spherical retrograde Moon which passes in front of the automaton, following its precise 29.5-day cycle.

This movement is regulated by an exceptionally large tourbillon — more than twice the size of the largest tourbillon the Manufacture has made for a wristwatch. Paired with a 16.8mm-diameter balance, it is contained in a 28mm cage in the form of Vacheron Constantin’s Maltese Cross and supported by a 43.3mm-long bridge. The tourbillon’s function to compensate for the effects of gravity on timekeeping precision is all the more valuable in La Quête du Temps which, unlike a watch, remains in a vertical position.

Clearly visible behind a magnifying glass, at 12 o’clock inside a circle of baguette diamonds, the tourbillon is mirrored at 6 o’clock by the 24-hour scale – with divisions for day and night –, which is also framed by a circle of baguette diamonds.

On the outer edge of the dial, retrograde hours in Roman numerals, on the left, and retrograde minutes in Arabic numerals, on the right, are given in rock crystal semi-circles. Comprising four transparent layers designed as a series of arcs, curves and circles-within-circles, this remarkable dial displays the indications for the perpetual calendar in apertures, with days at 10 o’clock and months at 2 o’clock. As for the retrograde date, it appears in a semi-circle just below the 24-hour dial and is shown by a Sun/Moon.

There is also a leap-year indicator, in a small aperture to the right of the tourbillon, and a power-reserve display in two semi-circles, each graduated for 7.5 days or half of the total 15-day reserve.

On the reverse side, a dial depicting the celestial vault for the Northern Hemisphere tracks the movement of the constellations in real time, thus measuring the sidereal day, which is approximately four minutes shorter than the 24 hours of the solar day that defines civic time. As well as an additional power-reserve indication in a semi-circle at 12 o’clock, this dial is framed by two concentric circles, one of which displays the months by number, the seasons and the equinoxes while the outer circle is inscribed with the astrological zodiac signs.

In total, La Quête du Temps assembles 22 watchmaking complications, to which we can add the Astronomer automaton, a complication in its own right. The Astronomer’s smoothly flowing movements, controlled by 158 cams, constitute a remarkable innovation, as does the retrograde Moon. A de facto second automaton, it travels along an arc following a cycle of 29.5 days. Constructed in two layers, with its own mechanism and its own barrel, it is linked to both the Astronomer and the movement. It too constitutes a first in horology, for which one of the seven watchmaking patents has been filed (out of the total 15 patent applications).

Other patents include the system that enables the clock mechanism to be driven by two escapements operating in different ways, and the novel power-reserve mechanism which enables the two separate displays to operate consecutively (each showing one half of the 15-day total reserve, as mentioned).

Monumental, transparent and precious

Such a monumental and large-scale work could have overwhelmed were it not for the decision to make La Quête du Temps entirely transparent — which also does justice to the doubly complex kinematic and musical mechanism in its base, invented by François Junod and which springs to life whenever the Astronomer is activated.

Measuring 40cm in diameter, the glass dome above the automaton raised a challenge of its own. It had to be light, solid and stable, with a support that was sufficiently strong without detracting from its aesthetic. The solution would be to build arch-shaped supports similar to the spherical framework around an armillary sphere.

Every last detail has been scrutinised. Finishing, such as the hand-polishing and chamfering of the tourbillon cage, is of a standard that does not tolerate the slightest imperfection; in a work on this scale, the tiniest flaw would be visible to the naked eye. Multiply this by the 2,370 components of the mechanism, and the sheer immensity of the task becomes apparent.

Space does not permit us to list every one of the materials used nor each of the crafts employed. By way of example, the pedestal supporting the clock is crafted from plaques of lapis-lazuli, inset with hard-stone marquetry representing the planets in the solar system: azurite for Earth, red jasper for Mars, crazy lace agate for Jupiter, silver obsidian for Mercury, etc. The name of each planet is written in mother-of-pearl.

The reverse dial, whose centre carries a map of the celestial vault that makes a complete rotation in one sidereal day or 23 hours, 56 minutes and 4 seconds, is sculpted from mineral glass, which is engraved with the stars and constellations that are inked with gold colour. Framing this dial is a circle of moonstone marquetry that has 12 sections of rock crystal marquetry in its centre. This same rock crystal serves for the finely engraved panels which envelop the octagonal base protecting the automaton mechanism.

The months, seasons, solstices and equinoxes are in Grand Feu enamel. Different engraving techniques were used for different elements, for example the delicate engraving of the constellations on the Astronomer’s body, or the rays spreading out from the Sun/Moon 24-hour indicator, which are hand-guilloché in high relief.

The celestial vault on the Astronomer’s glass dome is decorated with miniature painting. Adding to the already immense difficulty of working completely freehand, through a binocular magnifier and with no room for error, the design is on the inside of the glass, hence the artist had to paint the constellations back-to-front and upside-down. In all, three weeks of intense physical and mental concentration, after more than six months of research and trials.

There is so much more to be said about this breathtaking Quête du Temps.

The last word must go to Christian Selmoni, Style & Heritage Director at Vacheron Constantin: “The key to the entire project was bringing together different people who are equally passionate and equally talented – people willing to dream together, to challenge each other and to support each other’s ideas. At every stage, we wanted to go further. It was a continuous process of creativity but we never lost the element of fantasy and play. It has been a shared human adventure on a grand scale.”