To understand how such an old complication could be improved, we have to briefly study a more scarcely discussed “issue” with moon phases and horology. Basically, the source of the problem lies in mathematics and making it work at the level of gears and ratios. The average synodic month (the time that elapses from new moon to new moon) lasts 29 days, 12 hours, 44 minutes, and 3 seconds. And while creating a gear train that allows such fine measurement of cycles would be possible, fitting it into a wristwatch is a completely different challenge altogether. Therefore, for the sake of simplicity, most movements will measure 29.5 days and just let the 44 minutes “slide.” If you think about it, that is a considerable deviation and ultimately these minutes add up and within 2.5 years, cause the ordinary mechanism to be late by an entire day.

What you see above is Lange’s solution for the problem. It is apparent that the moon disc is driven by what appears to be a set of two gears. What you cannot see on this image is that the gear train actually consists of not two but seven wheels and that it is linked to and continuously driven by the “hour-wheel continuum.” It is an ingenious solution and the results are equally impressive as well. It is accurate to 99.9978% which practically means that for one day’s worth of deviation to occur it takes not 2.5, but 122.6 years. Unless you let your watch wind down, that is! Inside the Grand Lange 1 Moon phase is the in-house made, hand-wound L095.3 movement with 72 hours of power reserve – or Gangreserve, as it proudly states on the dial. And while three days of power reserve is substantial, should the watch run out of power reserve and stop, the moon phase can be quickly re-adjusted with the pusher on the side of the case, located between 7 and 8 o’clock.

At the end of the day however, this complication is an astronomical indication and as such, its desirability is to be found not in the sheer pursuit of accuracy, but somewhere else, in something less tangible. The modern watch making industry tirelessly develops different escapements, tourbillons, funky materials and, in general, technologically mind-blowing solutions for those interested in unearthly accuracy. Moon phase indications, on the other hand, have traditionally been a more relaxed and – for the lack of a better word – more poetic complication. It should primarily be about creating emotions and that is first and foremost achieved by the way it enhances the aesthetics of a timepiece. This tiny display adds the blue of the heavens and a look at the stars that the metropolitan businessman scarcely gets to admire. For this reason Lange & Söhne developed and patented a new coating process that is used during the manufacturing of the Moon disc so as to ultimately “create an intense blue tone and produce a miniaturized image of the galaxy.”

Miniaturized image of the galaxy it is not, but absolutely stellar to look at – it undoubtedly is. I will go ahead and say that I love how they managed to go excessively nerdy in creating something that has no other function than aesthetically enhance this complication. The Grand Lange 1 Moon phase in essence then is a beautiful piece that features some appreciable improvements and developments compared to its predecessors, and does so without upsetting the established values of the company and its most important collection. It will be available in yellow gold and pink gold cases for €38,900 and in platinum for €50,900, that is around $53,000 and $69,000 respectively. alange-soehne.com