Amonth was usually the amount oftime it took for amoon toorbit itsplanet. This was usually a portion of ayear, and a large number ofdays (in which case it may be broken down intoweeks).
On planets without moons, a month could either A) not exist, B) be equal to a season, or C) be a fractional division of a season. For example,Vulcan "has no moon", so it is unknown what portion of a year is represented by the "month" ofTasmeen. Thenovelization ofStar Trek: The Motion Picture could be read to imply that Vulcan's "months" are whole seasons.
OnEarth, a month was originally the length of the lunar cycle (29.53 days). Most calendars at some point made the month one twelfth of a solar year (30.44 days). In Earth's most common calendar, the months were either 30 or 31 days long, with one shorter month (February) having 28 or 29 days depending on the year.
InAugust2151,Matthew Ryan toldTravis Mayweather he ate his laststeakeighteen monthsprior. (ENT: "Fortunate Son")
On anuninhabited planet it only experiencednight four days a month due to itsbinary stars. (ENT: "The Catwalk")
Months of the year | |
|---|---|
| Earth months | |
| Qo'noS months | |
| Vulcan months | |