What is a Moon Phase Watch?
Its time to pay attention to the fabulous complication on many watches -the moon phase. A complication is any feature on your watch that is not directly related to the time display.
This particular complication tracks the 29.5 day lunar cycle (or 29 days, 12 hours, 44 minutes and 3 seconds to be exact) with some clever engineering and show it in an aperture on the dial, with many beautiful designs and true craftsmanship. They are a striking eye-catching feature and have an army of collectors out there.
There are two types of moon phase complications - one is a radial moon phase watch; showing the progress of the lunar cycle by an indicator hand. The other, the most common, is a bosom moon phase watch, which physically depicts the moon in its various phases.
How do they work?
Complications are just that - complicated. The moon phase works with discs showing two moons, only one of which is visible at a time, controlled by a tooth driving wheel - usually with 135 teeth on that wheel - which uses a mechanical finger to advance the disc once per day. The watches with 135 teeth will be off by one day every 122 years - a marked improvement on the first moon phases and their 59 toothed wheel, which were out every 2 to 7 years on average.
There are now quite a few watches claiming their moon phase complication is accurate for thousands of years. Just incase 122 years isn’t long enough for you.
And topping them all is Andreas Strehler and his Sauterelle à lune perpétuelle, which has a moon phase display that only deviates by one day every 2.06 million years. Price for that accuracy is upwards of 125,000 USD.
So why do people want a moon phase watch?
Knowing we run our days by the sun and not the moon, and the added fact your smart phone can tell you any lunar phase at any moment, you might wonder why you’d want a moon phase on your watch.
But man has always been fascinated by the moon. Its part the allure and vintage look, its part the fact your watch knows the moon cycle and shares it on your wrist without the wifi being involved. Its the amazing skill of the complication and its the beauty of just how it looks.
Watch Buyers often have watches with this complication available, two examples are linked below.
