For Only Watch 2009, Patek Philippe has created a unique Ref. 5106 by adding a date display and other special features to the Celestial Ref. 5102. This one-of-a-kind piece is crafted in rose gold with a special guilloché pattern on the 22k rose gold bezel. The soft 22k gold allowed the unique guilloché pattern to be applied with a special hand tool created just for this watch.
This timepiece displays the northern hemisphere night sky rotating counterclockwise, showing the angular progression of the stars relative to the meridian passage of Sirius. At the same time, the display shows the angular position of the moon, its phases and meridian passage. The astronomical displays are created by a series of stacked sapphire crystal discs rotating at different speeds. The celestial background is a blue sapphire crystal disc on a wheel with 279 teeth. This disk reproduces the orbit of the moon, and via a planetary gear train, it also drives a subsidiary crystal disc depicting the waxing and waning of the moon in a small round aperture. Above it, on a wheel with 356 teeth, is a transparent sapphire crystal disc bearing the sky chart on one side and an image of the Milky Way galaxy on the other. For this invention, Patek Philippe was awarded Swiss Patent CH 688 171 B5.
The exhibition case back allows you to view the movement, which consists of 315 parts. The edges of all steel components are beveled and polished, and each tooth of each gear wheel is manually polished with a rotating hardwood disk to reduce friction at the wheel contact points.
This unique timepiece will be offered on September 24 at the Only Watch auction conducted by Patrizzi & Co. during the Monaco Yacht Show. The auction enjoys the high patronage of HSH Prince Albert II, and all proceeds of the sale go to support research into Duchenne Muscular Dystrophy.