Jaeger-LeCoultre introducing the new addition to their Master Ultra Thin collection. To epitomise their philosophy of uniting technical virtuosity with enduring beauty, this new model that is called Master Ultra Thin Tourbillon Moon comes with a moon phase and a tourbillon, the two of horology’s most cherished complications.

For this new model, Jaeger-LeCoultre’s engineers capitalised on the 978 movement to develop the new Calibre 983, with the addition of the moon phase and ‘jumping’ date complications.

The triple moon phase indicator displaying the age of the moon as well as its phases in both Hemispheres is also a recent development, having been introduced last year. Beating at a frequency of 28,800 vph (4 Hz), the new Calibre 983 offers a power reserve of 45 hours.

The Master Ultra Thin Tourbillon Moon is presented in a case made of Le Grand Rose gold. Introduced this year, the new pink gold alloy has a remarkable sheen and depth of colour, and is highly resistant to fading over time. True to the classically elegant design codes of Master Ultra Thin, the case is fully polished, with elongated and bevelled lugs and a fine bezel.

Complementing the warmth of the pink gold, an eggshell-white dial provides a restrained backdrop that places all the emphasis on the moon phase display and tourbillon. Adding to the sense of refinement, the shape. Meanwhile, the several key details marked in red, to increase legibility and add a discreet touch of colour.

The astronomical complication displays the Northern Hemisphere moon phases in the traditional way, a deep blue sky scattered with stars provides the background for a polished golden disc. Surrounding this is a ring with applied Southern Hemisphere moon phases on the left and the Age of the Moon on the right, each indicated by a double-ended hand.

For the peripheral date display the Manufacturer’s engineers chose Jaeger-LeCoultre’s signature ‘jumping’ complication. Every month, the date hand makes a 90-degree jump, gliding rapidly from the 15th to the 16th, in order not to obscure the tourbillon.

The lower half of the dial is dominated by the tourbillon. A newly designed bridge in polished pink gold secures the titanium tourbillon cage (which weighs around 0.3 grams with its components) as it completes one revolution every 60 seconds. The fine tourbillon bridge and wide aperture maximise transparency and light, drawing the eye right through the mechanism.

On the reverse side, the long span of the open-worked tourbillon bridge further enhances this transparency, while its Côtes de Genève decoration complements the sunray pattern of the stripes on the main plate. The open-worked pink gold winding rotor, which features the JL logo and a combination of polished and micro-blasted surfaces, allows a clear view of the movement, with additional fine finishes including blue screws, circular graining and chamfered bridges.