Conversion Center
Search a unit
Convert metonic cycle (Enneadecaeteris) to hipparchic cycle
Selected category: time.
Definition and details for metonic cycle (Enneadecaeteris):
The Metonic cycle or Enneadecaeteris, is a particular approximate common multiple of the tropical year and the synodic (lunar) month. The Greek astronomer Meton of Athens observed that a period of 19 tropical years is almost exactly equal to 235 synodic months, and rounded to full days counts 6940 days.
Definition and details for hipparchic cycle:
Hipparchus proposed to make a 1 day correction after 4 Calippic cycles. A Hipparchic cycle lasts 111035 days instead of 111036 days (4 Calippic cycles). He decided to make that correction, because he found that the tropical year is about 1/300 of a day shorter than 365 + 1/4 days that Calippus used. This is a very decent approximation for an integer number of lunations to an integer number of days (error only 0.014 days).
Swap, do a hipparchic cycle to metonic cycle (Enneadecaeteris) conversion.
