Containing the cosmos within its case, the Patek Philippe Celestial Grand Complications ref. 5102 was launched in 2002 as one of Patek Philippe’s most important modern horological developments. Boasting the Northern Hemisphere’s celestial chart within its display, the ref. 5102’s rotating sapphire disk rotates counter clockwise, showing the progression of stars relative to the meridian passage of Sirius. This essentially allows the watch to display the portion of the Milky Way galaxy’s stars that would be overhead during any given night provided the correct conditions of total darkness and a clear sky were present. Launched in 2009 as the last variant to be produced, the ref. 5102RG that we have here features a two-tone construction with a large 43mm 18kt rose gold case that sports a platinum bezel, caseback, and a matching platinum deployant clasp for its leather strap. Finished with an extravagantly engraved mid-case to complement its bright blue three-layer display, this timepiece just about has everything a collector could want from a watch of this calibre and pedigree.

A grail to so many collectors and Patek Philippe aficionados, the Celestial Grand Complications ref. 5102 is one of the ultimate expressions of Patek Philippe's ability to take off-the-wall horological concepts and distil them into wonderfully executed and tremendously impressive pieces of watchmaking.