The Moon
Lunation
Say it: loo-NAY-shun IPA: /luˈneɪʃən/ noun
Lunation: One complete cycle of lunar phases, usually measured from one new Moon to the next.
A lunation lasts about 29.53 days on average. It is longer than a lunar orbit measured against the stars because Earth and the Moon also move around the Sun.
- Example
- The observing journal followed one lunation from a thin crescent through full Moon and back.
- Why astronomers use it
- It is a useful unit for lunar calendars and recurring observing conditions.
- Tiny cosmic connection
- Individual lunations vary in length; 29.53 days is an average, not an exact duration for every cycle.
Observatory The Moon
Where to check it
Written for Cool Moon Facts in its own words; the sources cover the same idea in more depth.