Challenges and Questions

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The ultimate goal is to extend this calendar
from Year 1 to year 3000


      My goal is to set January  1 to always straddle the perihelion in less than 3.4 days. Now of course I have not been able to get precisely the amount of time the Gregorian is either ahead or behind the solar year at midnight on the following date December 31, 2023. The rate of precession of the earths orbit is about 26,000 years or about 0.0000385 days per year. This is counter-clockwise and has to be added in. The earths year is about 365.2525 days per year. Consequently, when I do get more accurate data some future leap year dates may change.



     !. I have found out that these are not a stable numbers. I need some way to get them correct to dozen digits, for every year, so I can make a 3,000 year calendar centered on the perihelion.

     2. Since the earths orbit and precession vary over the centuries, how do I get that data?

     3. How much will that affect calculations ?

      4. For the long term accuracy I would like an agreement on set of data to a dozen digits. After 3,000 years it probably will not matter.




    1. Someone needs to calculate all the years from 1 to 3000 with a better accuracy than I have been able to. It will have to calculated backwards from January 1, 2024. See calculations page. For page size I have not included all 3000 years. After that it will not matter.

     2. An observatory, government agency. NASA, JPL or someone who will make a way for all of us to convert between other calendars either to or from the corresponding dates for free!



    1.The leap years must be fully agree on, before they chiseled in granite.

    2. This is so that all devices that use or inbreed the calendar can be guaranteed that they will never change in the future, right or wrong.


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