Convert millenium (Julian) to callippic cycle
Selected category: time.
Definition and details for millenium (Julian):
A period of time equal to one million Julian years is a millenium.
Definition and details for callippic cycle:
Callippic cycle, in astronomy and calendar studies, is a particular approximate common multiple of the the tropical year and the synodic month. It was proposed by Callippus in 330 BC. Callippic cycle is a period of 76 years, as an improvement on the 19-year Metonic cycle.
A Metonic cycle was invented by Meton and lasts 6940 days. This means that a solar year is 365 d 6 h 18 min 56 s, but Callippus knew that year length was more closely to 365 + 1/4 days. So he multiplied the 19-year cycle by 4 to reach an integer number of days and dropped 1 day from the last 19-year cycle. Thus he constructed a cycle of 76 years that contains 940 lunations or 27,759 days.