A year is the orbital period of a planetary body, for example, the Earth, moving in its orbit around the Sun. A calendar year is an approximation of the number of days of the Earth's orbital period, as counted in a given calendar. The Gregorian calendar, or modern calendar, presents its calendar year to be either a common year of 365 days or a leap year of 366 days, as do the Julian calendars. For the Gregorian calendar, the average length of the calendar year (the mean year) across the complete leap cycle of 400 years is 365.2425 days. In astronomy, the Julian year is a unit of time; it is defined as 365.25 days of exactly 86,400 seconds (SI base unit), totalling exactly 31,557,600 seconds in the Julian astronomical year
Standard Units | |
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Callippic Cycles | {{callippic_cycles}} |
Century | {{century}} |
Days | {{day}} |
Decade | {{decade}} |
Hours | {{hour}} |
Lustres | {{lustre}} |
Millennium | {{millennia}} |
Millisecond | {{millisec}} |
Miniutes | {{min}} |
Moments | {{moment}} |
Month | {{month}} |
Nanoseconds | {{nanosec}} |
Seconds | {{sec}} |
Sothic Cycle | {{sothic_cycles}} |
Weeks | {{week}} |
Years (Julian) | {{ju_year}} |
Year (Tropical) | {{tr_year}} |