Walter said:
> The Julian Day system is based on the Easter cycle Scaliger's invention of the Julian Period of 7980 years is based in part on the number of years (19) in the Metonic Cycle. (7980 is the least common multiple of 28, 19 and 15.) The "Easter cycle" is also based on the Metonic Cycle. But this does not imply that Scaliger's Julian Period is based on the Easter cycle. The Julian Day Number system was not part of, or implied by, Scaliger's invention. That system was invented in 1849 (or earlier) by the astronomer John W. F. Herschel, who defined "Julian Day Number" as the number of days since the first day of Scaliger's Julian Period, namely, 47120101 JC (which is JDN 0). For more on this see "Julian Day Numbers" at https://www.hermetic.ch/cal_stud/jdn.htm Regards, Peter 
Dear Peter et al Thank you for clarifying that It is interesting to note that the beginning of the Julian Date system is 248 Metonic cycles before Julian year 1 BC WalterZiobro On Friday, March 22, 2019 Peter Meyer <[hidden email]> wrote: Walter said: > The Julian Day system is based on the Easter cycle Scaliger's invention of the Julian Period of 7980 years is based in part on the number of years (19) in the Metonic Cycle. (7980 is the least common multiple of 28, 19 and 15.) The "Easter cycle" is also based on the Metonic Cycle. But this does not imply that Scaliger's Julian Period is based on the Easter cycle. The Julian Day Number system was not part of, or implied by, Scaliger's invention. That system was invented in 1849 (or earlier) by the astronomer John W. F. Herschel, who defined "Julian Day Number" as the number of days since the first day of Scaliger's Julian Period, namely, 47120101 JC (which is JDN 0). For more on this see "Julian Day Numbers" at Regards, Peter

In reply to this post by Peter Meyer
Walter said:
> It is interesting to note that the beginning of the Julian Date > system is 248 Metonic cycles before Julian year 1 BC Yes. Karl might be able to throw light on the esoteric significance of this. But strictly speaking there's no "Julian Date system". There is, however, a "Julian Day Number system". There's also a "Julian date", which term can refer either to a date in the Julian Calendar (which is the more common meaning) or a real number whose integer part is a Julian Day Number. For more see https://www.hermetic.ch/cal_stud/jdn.htm#different_meanings Regards, Peter 
In reply to this post by Walter J Ziobro
Dear Walter and Calendar People
The Julian Day epoch was chosen to the start of the Julian Calendar year (Jan 1) whose Golden number is 1 and so this is no surprise. It was also chosen to be at the start of the 28year Solar Cycle (better named Sunday cycle) and the 15year indiction cycle. Karl Monday Delta March 2019
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