AstronomyPerpetual Moon 41.5 PlatinumEvery part of this piece evokes the radiance of the night, from the dial stamped with the House’s “Stellar Rays” decor to the moon disc in a grained sky and the navy-blue alligator-leather strapBlue MoonArnold & Son continues to explore the theme of moon phases with a constant eye for detail and decoration. After revisiting the design of the Perpetual Moon, this celestial-blue version is joining the collection. As always, in the backdrop, the moon-phase complication is accentuated to striking effect. In a platinum case measuring 41.5 mm in diameter and 11.30 mm thick, Perpetual Moon 41.5 Platinum “celestial blue” presents the largest of all moons.Moon Phasessky: grained, with midnight-blue PVD treatmentconstellations: hand-painted, enhanced with Super-LumiNovamoons: mother-of-pearl discs enhanced with Super-LumiNova, hand-painted detailsConstellationsThe large white mother-of-pearl moon is realistically rendered with hand-painted shadows and coated with Super-LumiNova. It is placed on a grained sky featuring a midnight-blue PVD treatment. Following the tradition of the Perpetual Moon collection, it is surrounded by the Big Dipper and Cassiopeia constellations, which are also hand-painted and coated with luminescent material.The constellations have been chosen as a reference to John Arnold’s history as a maker of naval chronometers. The Big Dipper and Cassiopeia have been used as points of reference since time immemorial.