One of the most complex wristwatches ever made
There's one complication that I've seen in another watch and that puzzles me a lot.<p>On its back this watch has sunrise/sunset times. These times are derived from a so-called sunrise equation [1] which depends on the day of the year <i>and</i> the latitude, and is expressed via trigonometry functions.<p>I can see how this can be translated into some sort of irregularly shaped gear(s) if there were a single variable (the day of the year), but I have no idea how one could also allow for different latitudes.<p>Does anyone know or care to guess?<p>[1] <a href="https://en.wikipedia.org/wiki/Sunrise_equation" rel="nofollow">https://en.wikipedia.org/wiki/Sunrise_equation</a>