The 41.5 mm diameter Constant Force Tourbillon 11 watch in 18-carat yellow gold, released by Arnold & Son as a limited edition of 11, is driven by a hand-wound mechanical movement. Equipped with two barrels to give a 100-hour power reserve, this timepiece was entirely developed and built at the manufacture in La Chaux-de-Fonds. It is fitted with a constant force mechanism visible on the enamel dial and is regulated by a tourbillon that can be seen on the back. The architecture of this calibre is inspired by that of the timekeeping instrument driven by the first tourbillon created by Abraham-Louis Breguet in 1808, based on a chronometer movement designed by John Arnold. This first tourbillon regulator, now in the British Museum, was given to John Roger Arnold by the Paris-based watchmaker in honour of his scientific collaboration and friendship with his father. The Constant Force Tourbillon 11 timepiece, designed to mark the end of the 260th anniversary celebrations of John Arnold’s legacy, pays tribute to the watchmaker’s ingenuity and his close association with Abraham-Louis Breguet.

The greatest watchmakers of the Age of Enlightenment often knew each other. Some of them exchanged views and appreciated each other despite language barriers and political obstacles. And this was the case with John Arnold and Abraham-Louis Breguet. These two watchmakers, undoubtedly the most productive of the second half of the 18th century, forged a friendship that nothing could shake, not even the throes of war between the two countries or the French Revolution. Aware of their respective talents, during Abraham-Louis Breguet’s frequent trips to London between 1789 and 1791, they shared their views and knowledge of the principles of timekeeping, furthering the science of timekeeping, which in their eyes definitely knew no frontiers.

Armin Strom co-founders Serge Michel and Claude Greisler look back on 15 years of achievements including 17 exclusive movements, patents, unique designs and 97% in-house production depth. 15 years ago, Armin Strom transformed from a one-man show to a fully integrated manufacture brand when entrepreneur Serge Michel and master watchmaker Claude Greisler took over the reins.

Since 2009, the two childhood friends have been dedicating their lives to the science of movement, building up an independent manufacture with a team of 38, including 22 skilled watchmakers able to turn raw steel bars into hundreds of complex, interconnected watch components. So far, this has resulted in 17 brand-unique different calibres with a signature open-worked design divided among the brand’s three main pillars: System 78, Resonance and Masterpiece.

Time and space converge in the latest masterpiece of haute horlogerie: the Grand Planetarium Eccentric Meteorite. This extraordinary timepiece is crafted from a genuine meteorite fragment—once part of an asteroid’s core, drifting through space for billions of years before falling to Earth 50,000 years ago. Now, this celestial relic has been transformed into an exceptional watch, uniting cosmic heritage with unparalleled horological innovation.

At the heart of this timepiece lies a groundbreaking complication: the Eccentric Planetarium, the only mechanical Grand Planetary Complication in the world that accurately displays all eight planets—Mercury, Venus, Earth and her Moon, Mars, Jupiter, Saturn, Uranus, and Neptune—moving in real time around the Sun. This breathtaking mechanism captures the celestial dance of our Solar System with unmatched precision, making it a true marvel of both astronomy and watchmaking.

A Celestial Fusion of Science and Art
Master watchmaker Pim Koeslag has meticulously sculpted this timepiece, ensuring that its construction reflects the grandeur of its cosmic origins. The meteorite case, weighing 47 grams, is carefully crafted out of a 1.09 kg space stone. This extraordinary material shaped by the universe itself, features a unique Widmanstätten pattern, formed over millions of years of slow cooling in space, making each case truly one of a kind.

The dial is a celestial spectacle in itself: crafted from aventurine glass (goldfluss), it mimics the night sky, complete with zodiac constellations. The Eccentric Planetarium features hand-painted planetary orbits, while the meteorite dial ring, set between Mars and Jupiter, signifies the asteroid belt and contains real fragments of a martian nakhlite meteorite —a piece of another world encased within this exceptional timepiece.

A Timepiece Beyond Time
Encased in domed sapphire crystal, the 44mm meteorite case showcases the celestial ballet within. The sapphire crystal case-back reveals the movement’s intricate craftsmanship, while the dark blue hand-stitched leather strap and platinum folding clasp complete this cosmic masterpiece.

“The Grand Planetarium Eccentric Meteorite is more than a watch. It is a link between humanity and the cosmos, a way to wear the universe on your wrist,” says Pim Koeslag.

This timepiece is a tribute to time itself. From a star’s death to an asteroid’s journey, from its fall to Earth to its transformation into an exceptional watch—each second it measures is an echo of the vast cosmic history it carries.

An Exclusive, Limited Edition for Collectors
The Grand Planetarium Eccentric Meteorite is available in a strictly limited edition, with a maximum of 3 pieces, depending on the avaibility and quality of the rough meteorite material. So far, Christiaan van der Klaauw has been able to produce only 2 pieces from the available material, making this timepiece an exceptionally rare collector’s item. This extraordinary creation offers the unique opportunity to own a fragment of a star, forever marking the passage of time.

About Christiaan van der Klaauw
Christiaan van der Klaauw is one of the most prestigious watchmaking houses in the Netherlands, specializing in astronomical watches. Founded in 1974, the brand has distinguished itself by its ability to integrate astronomical complications innovatively and artistically into high-precision timepieces. The Grand Planetarium eccentric model is one of its most iconic Grande Complication, representing the quintessence of art and science.

To celebrate the 20th anniversary (2004-2024), Greubel Forsey presents its 10th Fundamental Invention: the Nano Foudroyante EWT. The mechanism’s energy is managed at the nanojoule scale, significantly reducing the number of components and the overall dimensions. The result is a 37.9mm timepiece that combines the world’s first perpetual Nano Foudroyante with Greubel Forsey’s first flying tourbillon and manual wind flyback. This timepiece, set in a white gold and tantalum case, will be limited to just 11 pieces.