Patek Philippe A very fine 18ct gold automatic astronomical wristwatch with sky chart, phases and position of the moon and time of meridian passage of Sirius and the moon ref 5102J-001 mvt 3580271 case 4464141 Celestial circa 2009

PROPERTY FROM THE COLLECTION OF THE LATE MR JAMES WOODWARD, SYDNEY

Cal. 240 LU CL automatic movement stamped with the Geneva seal, 45 jewels, 22ct gold mini-rotor engraved with the Calatrava cross, inner blue bezel with silvered Roman numerals, the sapphire crystal glass with silvered ellipse framing the visible sky (marked out with the cardinal points), planisphere of the Northern Hemisphere rotates counter-clockwise above the dial, skeletonised white-lacquered feuille hands, circular case band finely decorated with halved Calatrava crosses, crown at 2 o'clock for time setting, crown at 4 o'clock for adjusting the planisphere by turning to one direction and in the other direction to correct the angular position and moon phases, screw-down sapphire crystal case back, case, crystal and movement signed, with an 18ct gold Patek Philippe buckle, diameter 43mm.

Accompanied by a Patek Philippe Certificate of Origin, papers, presentation folder, facsimile J Farren-Price invoice, cardboard travel box and presentation case.

In 2002 Patek Philippe released the Celestial (Ref. 5102) which is considered one of the most important horological complications ever developed. A remarkable rendition of the Northern Hemisphere's celestial chart is fitted dynamically upon the wrist for the first time. The celestial chart rotates counter clockwise, showing the progression of stars relative to the meridian passage of Sirius. Simultaneously, the meridian passage and phases of the moon can be seen. 25 trillion (25,000,000,000,000) ratio combinations were researched by Patek Philippe to determine the greatest accuracy for all the Ref. 5102's displays.

These complications illustrate the tremendous challenges that the production of this highly sophisticated model posed to the company's watchmakers.

For a similar example see Important Watches, Sotheby's, Hong Kong, 2 April 2018, lot 2650, sold for 1,125,000 HKD (143,348 USD)

• Lot Sold $140,000 (Hammer Price)
• $170,800 (Hammer Price with Buyer's Premium)