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Re: using old nautical almanacs
From: Herman C
Date: 2009 Mar 15, 10:39 -0700
From: Herman C
Date: 2009 Mar 15, 10:39 -0700
Bill This is slightly off topic bur nevertheless pertains to leap year calculation. Bill wrote "In either case, baring surprises, the current leap years system seems to be good for thousands of years before it runs into trouble." It looks like the current Gregorian calendar leap year rule is good for 40,000 years and beyond. But sometime between 10,000 and 40,000 years if one leap year is eliminated then the number of days would be 365.24225 days which is more closer to desired 365.24222. First cycle Years days Total Average 3 365 1095 1 366 366 4 1461 365.25000 2nd Cycle 303 365 110595 97 366 35502 400 146097 365.24250 3rd cycle 3,031 365 1106315 969 366 354654 4,000 1460969 365.24225 4th cycle 30,311 365 11063515 9,689 366 3546174 40,000 14609689 365.24223 Also the Orthodox Church in 1923 when they synched their calendar with Gregorian calendar, adopted a different leap year rule.This leap year rule was proposed by the Serbian scientist Milutin Milankovi�, an astronomical delegate to the synod representing the Kingdom of Serbs, Croats and Slovenes.Years evenly divisible by four are leap years, except that years evenly divisible by 100 are not leap years, unless they leave a remainder of 200 or 600 when divided by 900, then they are leap years.Milankovi� selected this rule, which produces an average year length of 365.242222... days, because it was within two seconds of the then current length of the mean tropical year.(http:// en.wikipedia.org/wiki/Revised_Julian_calendar) According to Orthodox Church calendar, Years 2900 and 3300 would be leap years instead of 2800 and 3600. So followers of Orthdox Church may have buy new NA's in year 2800. Herman D. On Mar 12, 3:51 am, Billwrote: > George wrote: > > It would be nice if a mailing list such as ours offered a way to draw > > attention to an acknowledged mistake, after it has appeared. Not to allow a > > posting to be amended after the event, which could be dangerous tinkering > > with history, and never-ending. Instead, to allow the original contributor > > (and nobody else) to retrospectively add a tag which means, in effect- "the > > writer of this posting asks you to read it in context with later message > > number [xxxx] which will modify it in some way". I fear that I would use it > > often. > > LOL. The famed "unsend" key! And wouldn't it be dandy if print and > broadcast media that made a typo--or worse yet a fact-checking error (which > I have been guilty of on the list, as well as a major US of A network some > years ago)--could recall and reissue the publication instead of burying the > retraction of their mistake somewhere in the dark corners of the > publication? > > One of the downsides of a group such as ours is the lack of professional > proof readers and fact checkers. The author is naked. On the upside, we can > express an international smorgasbord of knowledge and opinions in almost > real time. If someone is interested in a topic discussed days, months, or > years ago Robert and Frank have made that information available. Like a > prudent navigator using all available data, I would hope one would read and > consider the entire thread/topic instead of taking one post as gospel and > note any errata posted. > > In my mind it is as simple as following up a post with a factual/non-fatal > grammatical error with a "PS" or "Error" message. Addressing the "If wishes > were fishes, our nets would all be full" portion of your posting, I too > abhor revisionist history, and such a feature would be handy. And if you can > imagine it, it can probably be done. Perhaps not tomorrow ;-) > > Bill B. --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---