====== Moon-phase indication ======

{{ https://www.uhren-wiki.com/images/Lunar_libration_with_phase2.gif|Animation of the moon phases}}


Watch function ([[complication]])

===== The phases of the moon =====
The moon always faces the earth with the same side. Based upon the fact, that the moon obtains its light from the sun (and at times a very small part from the earth the ashen earthshine which can be observed just before and after new moon), it is changing continuously its face this is called //new moon, waxing moon, full moon// and //waning moon//.

A lunar cycle lasts approximately 29.5 days. The result is that it appears at the sky from day to day about 50 minutes later (24 hours divided by 29.5).

===== Moon-phase indication =====
{{wst>image_l|A Lange & Söhne Cabaret Mondphase|[[A. Lange & Söhne Cabaret Moonphase]]\\ with **moon-phase indication**\\ © [[A. Lange & Söhne]]}}

A moon-phase indication is a rotating disk, shown in a dial section, that indicates the position of the moon - usually the way it presents itself at the observation of the Northern Hemisphere.

Because of the additional mechanics moon-phase indication is counted as a [[complication]].

Known watches with moon-phase indication were, for instance, the first models with which [[Blancpain]] in the early [[1980]]s rang the renaissance of the mechanical [[wristwatch]].

===== Literature =====
  *[[Das ZEITGEFÜHL-Uhrenbuch]]; Autor [[Gerd-Lothar Reschke]]; ISBN 3-938607-61-0


{{tag>Terms}}