The Sky Moon Tourbillon Ref 5002 was released in 2000. It is one of the most beloved within the Patek Philippe tourbillon collection of rarities. Ref 5002 features a case made of 18k white gold, measuring 42.8 mm in width. This was the first wristwatch from the brand to feature a double face to show off all the functions. There are 686 parts in the movement alone. It’s powered with a caliber R TO 27 QR SID Lu CL movement with minute repeater and tourbillon escapement. On the front is the perpetual calendar with retrograde date hand, hours, and minutes of mean solar time, Moon age, day, month, and leap year by hand. On the backside are the sky chart, phase and orbit of the moon, sidereal time, and correction of sky/moon indications.