Astronomy is the epitome of ultra-high-end watchmaking in the 21st century and a symbol of global recognition of Jacob&Co watchmaking expertise. Astronomy ranks first in the world in terms of its unprecedented conceptual courage and complete mechanical construction, not only surpassing impressive horological achievements, but also considered to be an outstanding multidisciplinary engineering achievement.
The astronomical tourbillon represents the essence of astronomy: this is a cinematic sculpture whose four-arm movement structure makes it move, rotates in its spectacular case and floats in a sapphire bound space. Full of unparalleled watchmaking solutions, supplemented by excellent watchmaking craftsmanship, the astronomical tourbillon has won an unparalleled iconic reputation in the field of high-end watches.
The four arms of the astronomical tourbillon are equipped with a three-axis tourbillon chronograph mechanism, the hand-painted blue magnesium metal spherical mirror cover represents the spectacular representation of the planet earth, the exclusive 288-faceted Jacob-Cut® 1 carat diamond, and the differential level , Skeletonized time display. This four-arm assembly completes the rotation around the center of the watches for men and the spectacular background in 20 minutes. Another amazing feature of the astronomical tourbillon is how each pair of opposing arms perfectly calculates each other’s counterweight-a testament to the unparalleled material engineering and watch movement design. By applying equal weight to these opposing arms, when the movement occupies different directions in space, the shaft will be free from stress and increase the tension.
The tourbillon was originally invented as a single-axis rotating cage, which can carry the adjustment mechanism of a mechanical pocket watch, thereby improving the chronograph performance, while the astronomical tourbillon brought this 224-year-old invention to a stunning modern elegance and Level of complexity.
The three-axis tourbillon of the astronomical tourbillon is at the forefront of modern watchmaking. The delicately decorated case of the three-axis tourbillon encapsulates the balance wheel, hairspring, escape wheel and many other vital parts. This outstanding tourbillon is characterized by a hollow cage that can rotate on three axes simultaneously. This is a set of superb parts, after professional assembly and fine-tuning, can make JCAM10 maintain accurate time in its 60-hour power reserve.
It takes 60 seconds for the first axis to fully rotate, which is a tribute to the traditional single-axis tourbillon. The second axis of rotation takes 5 minutes to complete, and the third axis of rotation can be achieved by the four-arm rotating platform of the astronomical tourbillon for 20 minutes. When designing with cutting-edge, ultra-modern technology and timeless watches cheap traditions, this gives a bold new look to how the tourbillon functions.
The dial of this timepiece is 3D hand-set with 103 sapphires (3.36 carats), 150 ice sapphires (2.27 carats), and 134 white diamonds (~3.31 carats). In such a spectacular timepiece, matching gemstones is very important, and it can take months or even years to find the correct matching color.
Jacob-Cut diamonds started out as larger rough diamonds. First, you must find a rough diamond that is large enough, whose inner and outer purity, clarity and color must reach the highest quality, and there must be no inclusions. If they start to cut the diamond and find inclusions, the entire diamond will be destroyed.
Next, the diamond is machined into a circle, the size is close to the final diamond.
Then, the gem cutter shapes the gemstone by hand, cutting out each individual face (288 pieces). This must be done slowly and carefully, because the stone must be perfectly round and symmetrical. The danger is that the stone will become rectangular instead of round. To be used in an astronomical collection, a Jacob cut diamond must be completely round and weigh exactly the same as the other three satellites (time display, three-axis tourbillon, and magnesium globe).
During this process, if the gem cutter applies too much pressure when adding facets, too many diamonds will be cut, and the ball will eventually be smaller than the required diameter. The cutting process requires at least two weeks of hard work.
In order to make the final one-carat 288-faceted Jacob cut diamond, more than half of the original rough diamond will be cut.
The complexity of hand-cutting 288 facets and ensuring that all objects are symmetrical and that the diamond is absolutely round makes the Jacob & Co. diamonds used in the astronomy collection so special.
The globe is made of blue-lacquered magnesium with golden continents to ensure weight consistency, because all four satellites must have exactly the same weight. The earth rotates in 30 seconds and travels on the dial for 10 minutes.
The case of the astronomical tourbillon has a diameter of 50 mm and a thickness of 25 mm, between the highest point of its specially curved front sapphire crystal and the lowest point of the case. Made of 18K rose gold or 18K white gold, each style is equipped with four sapphire crystal glass windows around the case, allowing unobstructed views of the spectacular movement inside.
The 3D time display sub-dial of the astronomical tourbillon is driven by an infinitesimal differential system. When it rotates in front of the astronomer with the four-arm platform of the movement, it always remains in the correct 12/6 position. The Roman numerals on the hollow dial are hand-engraved and painted with black varnish, while the hand-made hands are dark blue metallic.
Movement: Movement: Manufacturing Jacob & Co. Manual winding JCAM18; diameter: 40mm; height: 17.15 mm; components: 365; functions: hours and minutes; power reserve: 60 hours; frequency: 21’600 vib/h (3 Hz); gems: 42; finishing: plates and bridges: manual bend and polishing, side drawing, round grinding, polished sink; polished screws; barrel: round pattern; pinion: conical pinion; 4 Mechanical ball bearing device; balance spring.
System: 4-arm vertical movement, complete rotation around the central axis within 10 minutes; gravitational three-axis tourbillon, the first cage rotates within 60 seconds, the second cage within 2.5 minutes; 1 carat unique Jacobcut® diamond : 288 facets, can rotate within 30 seconds; magnesium blue painted globe, can rotate within 30 seconds; hour and minute dials, patented differential gear system ℗ can maintain 12/6 o’clock position.
Situation: Diameter: 50mm; Height: 25mm; Material: 18K White Gold; Side Sapphire Aperture; Case Back: 18K White Gold; Arch: The 18K white gold on the case back can be lifted and rotated through the “bow” for winding and timing. Front shell: 18K white gold; 3D setting 103 sapphires (approximately 3.36 carats), 150 ice blue sapphires (approximately 2.27 carats) and 134 white diamonds (approximately 3.31 carats); lugs: set with 80 baguette diamonds and white diamonds (≈ 6.10 carats); Crystal: unique hemispherical sapphire, anti-reflective treatment.
Dial and dial: Dial: titanium, polished and angled, lacquered hour markers; hands: blue finish.
Strap & Buckle: Strap: Alligator leather; Clasp: 18K white gold folding clasp is invisible inlaid with 22 rectangular white diamonds (≈1.4 carats).