The Lange 1 Moon Phase from A. Lange & Söhne, showcased at the 2017 Salon International de la Haute Horlogerie, incorporates a new indication as it combines the moon phase display with a day and night indicator.
The day and night indicator is explained in the article: A. Lange & Söhne Lange 1 Moon Phase: A different face.
How accurate is the moon phase display on the Lange 1 Moon Phase?
Lange’s moon phase displays are more accurate than simple moon phase mechanisms that are based on a lunar cycle of 29 days.
Lange’s moon phase display tracks the lunar moon cycle that is on average 29 days, 12 hours, 44 minutes and 3 seconds more accurately.
As such, it is only after 122.6 years that the moon phase display deviates from the true synodic period by one day. In other words, a one-day error of the moon phase display occurs only after 122.6 years.
The very first Lange 1 Moon Phase was introduced in 2002.
The 2017 Lange 1 Moon Phase is powered by the new Calibre L121.3 manual-winding movement. This is the brand’s 20th calibre with a moon phase display and it is based on the Lange 1 movement that was presented in 2015.
A. Lange & Söhne
Lange 1 Moon Phase
Introduced in 2017
• Calibre L121.3 manual-winding movement
• 438 components
• Movement diameter: 30.6mm
• Movement height: 5.7mm
• 47 jewels
• 21,600 vibrations per hour
• 72 hours power reserve
• In-house balance spring
• 8 screwed chatons
• Plates and bridges made of untreated German silver
• Balance cock engraved by hand
• Hours, minutes and subsidiary seconds with stop seconds
• Power reserve display
• Lange outsize date
• Moon phase display with integrated day/night indication
• Solid silver, argente dial, pink gold hands with luminescence
• Sapphire crystal (Mohs hardness 9)
• 38.5mm diameter case in pink gold, 10.2mm thick
• Hand-stitched red brown alligator leather strap
• Pink gold prong buckle
• Also available in white gold and platinum