What is Lunar year?
[[File:Lunar libration with phase2.gif|thumb|The moon throughout September if it is a lunar year.]] A '''lunar year''' (used in some calendars) of 12 synodic months (12 cycles of lunar phases) is about 354 days long. A cosmic year is the time (about 225 million years) needed for the [[solar system]] to revolve once around the centre of the [[Milky Way]]. [[Category:Calendars]]