CALENDAR: #scifi The Confederation calendar has slightly more than 364 days a year, with 4 of those days and whatever leap years are needed being considered outside the twelve 30-day months. “Day” and “year” are based on Central’s orbit and rotation rate, so the Confederation calendar does not quite match that of any other member planet of the Confederation. Most member planets have their own calendars, though year and day lengths are close enough to Central’s (and Earth’s) that matching is possible over a few fivedays’ time. The Confederation calendar is used to synchronize time across the Confederation as well as being the usual calendar on Central.
Calendar (Homecoming Glossary)