Patek Philippe

Launched in 2002, the Celestial (Ref. 5102) is 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. This gives some sense of the tremendous challenges that the production of this highly complicated model posed to the company's watchmakers.

Using a highly sophisticated automatic movement (calibre 240 LU CL), the movement uses 301 individual parts that are meticulously hand finished in the workshops of Patek Philippe. Three corundum sapphire crystal discs are used to simulate the orbit of the moon and the passage of the stars, inciting an incredible sense of depth. For this important invention, Patek Philippe was awarded a Swiss Patent for the base calibre (CH 688 171 B5).

The Ref. 5102PR was the final configuration for the reference. Released initially in white gold, followed by yellow gold, Ref. 5102PR was introduced at Basel in 2009 in a combination of platinum and 18k pink gold. The case design is sensational, with a powerful balance of color and texture. Ref. 5102 was discontinued in 2012 in favor of Ref. 6102, which has a redesigned case and includes a date complication to the celestial chapter ring.