Eclipic accuracy instead of uniform familiar month-lengths

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Eclipic accuracy instead of uniform familiar month-lengths

Michael Ossipoff
This email originated from outside ECU.

I initially chose the ecliptic-months' lengths in the same way as the designers of Indian National Calendar did:
.
Round each ecliptic-month's length to the nearest day.  But those rounded month-lengths only add up to 364. So one of the months must get an extra day.
.
The month that could receive the extra day with the least resulting error would be Aries (it seems to me that I found). But then Capricorn would have 29 days. Giving the extra day instead to Capricorn would only make 18 minutes more error than giving that extra day to Aries, and so I, and the designers of the Indian National Calendar, gave the extra day to Capricorn, in order to keep all the months' lengths 30 or 31 days.
.
But then today would be Capricorn the 30th instead of Aquarius the 1st, and the calendrical ecliptic-date would no longer match the astronomical ecliptic-degree of the astronomical ecliptic-month..
.
Of course it goes without saying that, due to the requirements for civil calendars, it isn't possible for a calendar to always give a perfect match between its ecliptic-date and the astronomical ecliptic-degree of the ecliptic-month.  But why not at least do as well as possible?
.
One possibllity would be to give the extra day to Aries, which minimizes the local error caused. Also, then the error doesn't start until a quarter-year later than it would start if the extra day were given to Capricorn.
.
But why settle for that?  Why not give the extra day (and the leapday too) to the last ecliptic-month of the year, Sagittarius?  Then the only error caused by the extra day or the leapday would be in the last day or two of the last ecliptic-month.
.
The whole point of these calendrical ecliptic-months is to maximize ecliptic-accuracy. I choose that instead of more uniform and familiar month-lengths of only 30 and 31 days.
.
So that's what I now propose for the South-Solstice Ecliptic-Months Calendar.
.
5 M
Aquarius 1st
Januarty 20th, 2020
.
1657 UTC
.
Michael Ossipoff


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Re: Eclipic accuracy instead of uniform familiar month-lengths

Jamison Painter
This email originated from outside ECU.

So the fundamental question here is simple: "Why?"

Before we contemplate a change in the current Calendar, which works quite well (although there are indeed better calendars out there, the FRC being only one of those), we need to ask ourselves what our purposes are. Before we do that, we really need to ask ourselves why calendars exist in the first place.

Calendars exist for several reasons. Let us enumerate those reasons below.

(A) A means of keeping track of seasons has been necessary since we lived in caves. We had to know when it was hunting/gathering season, so we would not starve in winter. As we shifted to an agricultural, settled way of life, we had to know when to plant, when to harvest, etc.

(B) All of the world's spiritual traditions have used calendars in order to time both moveable and immovable feasts, and other major sacred events. 

(C) Since the advent of the modern State, knowing how to deal with fiduciary matters has been of PRIME importance. The Government wants its taxes at a certain time, and woe betide unto the poor bastard that challenges that. This started to be a serious issue with the advent of Imperial Rome.

(D) Mankind has always had a fascination with astronomical events. A calendar is necessary to time such events, and know when they will occur. For that matter, calendars are largely BASED around those events, and the seasons.

Given the above four reasons for having a calendar, the next question becomes, which calendar best fulfills all four of them? Because Europe and the Euro-American  countries have been the predominant cultural force in the world, for both good AND evil reasons, the calendar used worldwide will of necessity be the calendar that is used by Europe and the Euro-American countries. To this date, that is the Gregorian Calendar. Other calendars have been tried, namely the FRC and Auguste Comte's Positivist Calendar, and one might include the Kodak Accounting Calendar, and even the Soviet Calendar. All of them have failed to meet the needs of the world as well as the Gregorian Calendar does, which is ultimately why they have been rejected.

If it were up to me, I would go with FRC. It is certainly more logical than the Gregorian Calendar, and it eliminates the hold that religion holds over everybody's life even those who are not Christian. But until a large number of people agree with me, the idea of changing the calendar is a pipe dream, regardless of the calendar you favour. 

Overall, we use the Gregorian Calendar because it works. Anything else may work as well or even better, but until it satisfies the needs of most people, it will not be adopted. Currently, the Gregorian Calendar (and no, I WON'T call it the "Roman-Gregorian Calendar. That is redundant. It's like saying "RSVP if you please". We know the Gregorian is Roman-based, both from the Ancient Roman month names, and even the modern fact that a Pope of Rome corrected a calendar that an Ancient Roman Dictator created based off the existing Roman Calendar. So no, I shall not be stupidly redundant.) satisfies the needs of most people. When it no longer does, then this discussion will have a point. Until then...

Jamison E. Painter, MA


On Mon, Jan 20, 2020, 10:57 AM Michael Ossipoff <[hidden email]> wrote:
This email originated from outside ECU.

I initially chose the ecliptic-months' lengths in the same way as the designers of Indian National Calendar did:
.
Round each ecliptic-month's length to the nearest day.  But those rounded month-lengths only add up to 364. So one of the months must get an extra day.
.
The month that could receive the extra day with the least resulting error would be Aries (it seems to me that I found). But then Capricorn would have 29 days. Giving the extra day instead to Capricorn would only make 18 minutes more error than giving that extra day to Aries, and so I, and the designers of the Indian National Calendar, gave the extra day to Capricorn, in order to keep all the months' lengths 30 or 31 days.
.
But then today would be Capricorn the 30th instead of Aquarius the 1st, and the calendrical ecliptic-date would no longer match the astronomical ecliptic-degree of the astronomical ecliptic-month..
.
Of course it goes without saying that, due to the requirements for civil calendars, it isn't possible for a calendar to always give a perfect match between its ecliptic-date and the astronomical ecliptic-degree of the ecliptic-month.  But why not at least do as well as possible?
.
One possibllity would be to give the extra day to Aries, which minimizes the local error caused. Also, then the error doesn't start until a quarter-year later than it would start if the extra day were given to Capricorn.
.
But why settle for that?  Why not give the extra day (and the leapday too) to the last ecliptic-month of the year, Sagittarius?  Then the only error caused by the extra day or the leapday would be in the last day or two of the last ecliptic-month.
.
The whole point of these calendrical ecliptic-months is to maximize ecliptic-accuracy. I choose that instead of more uniform and familiar month-lengths of only 30 and 31 days.
.
So that's what I now propose for the South-Solstice Ecliptic-Months Calendar.
.
5 M
Aquarius 1st
Januarty 20th, 2020
.
1657 UTC
.
Michael Ossipoff


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Re: Eclipic accuracy instead of uniform familiar month-lengths

Walter J Ziobro
In reply to this post by Michael Ossipoff
This email originated from outside ECU.

Dear Michael

It would be good when you refer to the Indian National Calendar to use the names of the used by them, at least for reference

Also, one way to resolve this issue would be to make the month in which the perihelion occurs a short month of 29 days in common years and a month of 30 days in leap years, with 6 months of 31 days distributed around the aphelion.

WalterZiobro




On Monday, January 20, 2020 Michael Ossipoff <[hidden email]> wrote:

This email originated from outside ECU.

I initially chose the ecliptic-months' lengths in the same way as the designers of Indian National Calendar did:
.
Round each ecliptic-month's length to the nearest day.  But those rounded month-lengths only add up to 364. So one of the months must get an extra day.
.
The month that could receive the extra day with the least resulting error would be Aries (it seems to me that I found). But then Capricorn would have 29 days. Giving the extra day instead to Capricorn would only make 18 minutes more error than giving that extra day to Aries, and so I, and the designers of the Indian National Calendar, gave the extra day to Capricorn, in order to keep all the months' lengths 30 or 31 days.
.
But then today would be Capricorn the 30th instead of Aquarius the 1st, and the calendrical ecliptic-date would no longer match the astronomical ecliptic-degree of the astronomical ecliptic-month..
.
Of course it goes without saying that, due to the requirements for civil calendars, it isn't possible for a calendar to always give a perfect match between its ecliptic-date and the astronomical ecliptic-degree of the ecliptic-month.  But why not at least do as well as possible?
.
One possibllity would be to give the extra day to Aries, which minimizes the local error caused. Also, then the error doesn't start until a quarter-year later than it would start if the extra day were given to Capricorn.
.
But why settle for that?  Why not give the extra day (and the leapday too) to the last ecliptic-month of the year, Sagittarius?  Then the only error caused by the extra day or the leapday would be in the last day or two of the last ecliptic-month.
.
The whole point of these calendrical ecliptic-months is to maximize ecliptic-accuracy. I choose that instead of more uniform and familiar month-lengths of only 30 and 31 days.
.
So that's what I now propose for the South-Solstice Ecliptic-Months Calendar.
.
5 M
Aquarius 1st
Januarty 20th, 2020
.
1657 UTC
.
Michael Ossipoff


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Re: Eclipic accuracy instead of uniform familiar month-lengths

k.palmen@btinternet.com
This email originated from outside ECU.

Dear Michael, Walter and Calendar People


I don't believe the Indian National Calendar was designed according to


"Round each ecliptic-month's length to the nearest day."


but is based on an Iranian Calendar with similar month lengths.


I think the Iranian and Indian National calendar month length rules are merely a simple month length sequence that puts the month starts near the ecliptic-month starts. If anyone has evidence to the contrary please provide it.


Walter's idea has the draw back that the leap day does not always occur at the end of the year. Instead one could have six 31s and six 30s with the perihelion near the start of the 4th 30, but with the last month of the year shortened by one day in a common year.


Karl


Tuesday Delta January 2020



------ Original Message ------
From: "Walter J Ziobro" <[hidden email]>
To: [hidden email]
Sent: Tuesday, 21 Jan, 2020 At 03:24
Subject: Re: Eclipic accuracy instead of uniform familiar month-lengths

This email originated from outside ECU.

Dear Michael

It would be good when you refer to the Indian National Calendar to use the names of the used by them, at least for reference

Also, one way to resolve this issue would be to make the month in which the perihelion occurs a short month of 29 days in common years and a month of 30 days in leap years, with 6 months of 31 days distributed around the aphelion.

WalterZiobro




On Monday, January 20, 2020 Michael Ossipoff <[hidden email]> wrote:

This email originated from outside ECU.

I initially chose the ecliptic-months' lengths in the same way as the designers of Indian National Calendar did:
.
Round each ecliptic-month's length to the nearest day. But those rounded month-lengths only add up to 364. So one of the months must get an extra day.
.
The month that could receive the extra day with the least resulting error would be Aries (it seems to me that I found). But then Capricorn would have 29 days. Giving the extra day instead to Capricorn would only make 18 minutes more error than giving that extra day to Aries, and so I, and the designers of the Indian National Calendar, gave the extra day to Capricorn, in order to keep all the months' lengths 30 or 31 days.
.
But then today would be Capricorn the 30th instead of Aquarius the 1st, and the calendrical ecliptic-date would no longer match the astronomical ecliptic-degree of the astronomical ecliptic-month..
.
Of course it goes without saying that, due to the requirements for civil calendars, it isn't possible for a calendar to always give a perfect match between its ecliptic-date and the astronomical ecliptic-degree of the ecliptic-month. But why not at least do as well as possible?
.
One possibllity would be to give the extra day to Aries, which minimizes the local error caused. Also, then the error doesn't start until a quarter-year later than it would start if the extra day were given to Capricorn.
.
But why settle for that? Why not give the extra day (and the leapday too) to the last ecliptic-month of the year, Sagittarius? Then the only error caused by the extra day or the leapday would be in the last day or two of the last ecliptic-month.
.
The whole point of these calendrical ecliptic-months is to maximize ecliptic-accuracy. I choose that instead of more uniform and familiar month-lengths of only 30 and 31 days.
.
So that's what I now propose for the South-Solstice Ecliptic-Months Calendar.
.
5 M
Aquarius 1st
Januarty 20th, 2020
.
1657 UTC
.
Michael Ossipoff


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Re: Eclipic accuracy instead of uniform familiar month-lengths

Walter J Ziobro
In reply to this post by Michael Ossipoff
This email originated from outside ECU.

Dear Karl et al

I believe that the Iranian calendar was based on Omar Khayyam's observations IMO Khayyam was trying to do something similar to Michael: have the months start close to ecliptic points 30 degrees apart from each other In fact sometimes the Iranian calendar has months of 29 days (near the perihelion) and even occasionally months of 32 days (near the aphelion)

WalterZiobro




On Tuesday, January 21, 2020 k.palmen <[hidden email]> wrote:

This email originated from outside ECU.

Dear Michael, Walter and Calendar People


I don't believe the Indian National Calendar was designed according to


"Round each ecliptic-month's length to the nearest day."


but is based on an Iranian Calendar with similar month lengths.


I think the Iranian and Indian National calendar month length rules are merely a simple month length sequence that puts the month starts near the ecliptic-month starts. If anyone has evidence to the contrary please provide it.


Walter's idea has the draw back that the leap day does not always occur at the end of the year. Instead one could have six 31s and six 30s with the perihelion near the start of the 4th 30, but with the last month of the year shortened by one day in a common year.


Karl


Tuesday Delta January 2020



------ Original Message ------
From: "Walter J Ziobro" <[hidden email]>
To: [hidden email]
Sent: Tuesday, 21 Jan, 2020 At 03:24
Subject: Re: Eclipic accuracy instead of uniform familiar month-lengths

This email originated from outside ECU.

Dear Michael

It would be good when you refer to the Indian National Calendar to use the names of the used by them, at least for reference

Also, one way to resolve this issue would be to make the month in which the perihelion occurs a short month of 29 days in common years and a month of 30 days in leap years, with 6 months of 31 days distributed around the aphelion.

WalterZiobro




On Monday, January 20, 2020 Michael Ossipoff <[hidden email]> wrote:

This email originated from outside ECU.

I initially chose the ecliptic-months' lengths in the same way as the designers of Indian National Calendar did:
.
Round each ecliptic-month's length to the nearest day. But those rounded month-lengths only add up to 364. So one of the months must get an extra day.
.
The month that could receive the extra day with the least resulting error would be Aries (it seems to me that I found). But then Capricorn would have 29 days. Giving the extra day instead to Capricorn would only make 18 minutes more error than giving that extra day to Aries, and so I, and the designers of the Indian National Calendar, gave the extra day to Capricorn, in order to keep all the months' lengths 30 or 31 days.
.
But then today would be Capricorn the 30th instead of Aquarius the 1st, and the calendrical ecliptic-date would no longer match the astronomical ecliptic-degree of the astronomical ecliptic-month..
.
Of course it goes without saying that, due to the requirements for civil calendars, it isn't possible for a calendar to always give a perfect match between its ecliptic-date and the astronomical ecliptic-degree of the ecliptic-month. But why not at least do as well as possible?
.
One possibllity would be to give the extra day to Aries, which minimizes the local error caused. Also, then the error doesn't start until a quarter-year later than it would start if the extra day were given to Capricorn.
.
But why settle for that? Why not give the extra day (and the leapday too) to the last ecliptic-month of the year, Sagittarius? Then the only error caused by the extra day or the leapday would be in the last day or two of the last ecliptic-month.
.
The whole point of these calendrical ecliptic-months is to maximize ecliptic-accuracy. I choose that instead of more uniform and familiar month-lengths of only 30 and 31 days.
.
So that's what I now propose for the South-Solstice Ecliptic-Months Calendar.
.
5 M
Aquarius 1st
Januarty 20th, 2020
.
1657 UTC
.
Michael Ossipoff


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Re: Eclipic accuracy instead of uniform familiar month-lengths

Michael Ossipoff
In reply to this post by Walter J Ziobro
This email originated from outside ECU.

Hi Walter--
.
You wrote:
.
It would be good when you refer to the Indian National Calendar to use the names of the used by them, at least for reference.
.
Yes of course, but they're difficult. And, even if I knew them, I couldn't assume that others would know what I meant.   ...which 3rd of which astronomical-quarter I was referring to.
.
And it's the same ecliptic-months, by either name.
.
To clarify which 3rd of which quarter I'm referring to, it would be best to say somthing like:
.
"Pisces, FromSouth3", or "Pisces, Feb-March".   Here, "FromSouth3" would probably be better. For a more general readership, "Feb-March" would probably be better.
.
Also, one way to resolve this issue would be to make the month in which the perihelion occurs a short month of 29 days in common years and a month of 30 days in leap years, with 6 months of 31 days distributed around the aphelion.
.
Sure, wanting to keep all the months 30 or 31 days long, I initially gave the extra day to the 29-day Capricorn, FromSouth1, and the leapday to Aries, ToNorth1 or to Gemini, ToNorth3.
.
But I value ecliptic accuracy more than familiar uniform month-length, and, by giving both the extra day and the leapday to Sagittarius, ToSouth3, the extra day and the leapday don't cause any ecliptic-error other than in the last day or two of the last month of the year.
.
5 Tu
Aquarius 2nd
January 21st, 2020
.
1946 UTC
.
Michael Ossipoff

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Re: Eclipic accuracy instead of uniform familiar month-lengths

Michael Ossipoff
In reply to this post by k.palmen@btinternet.com
This email originated from outside ECU.

merely a simple month length sequence that puts the month starts near the ecliptic-month starts

Fair enough, but I don't want the extra day or the leapday to cause any ecliptic-error other than to the last day or two of the last month.   Hench my giving of the extra day and the leapday to Sagittarius, ToSouth3.

5M
Aquarius 2nd
January 21st, 2020

Michael Ossipoff
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Re: Eclipic accuracy instead of uniform familiar month-lengths

Michael Ossipoff
In reply to this post by Walter J Ziobro
This email originated from outside ECU.

Walter--

Yes, Capricorn, FromSouth1,rounds to 29 days. Though none of the ecliptic-months round to 32 days, one of them, Cancer, FromNorth1, is nearly 31.5 days. 

I'm pleased to hear that the Iranian Calendar gave Capricorn, FromSouth1, 29 days, as I do.

Cancer, FromNorth1, is the ecliptic-month that comes closest to rounding up, and that would put it to 32 days, so there's justification for their giving it the extra day, or the leapday, and making it 32 days.

...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year.

5 W
Aquarius 3rd
January 22nd, 2020
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Invention of month names that usually result in making hash of the calendar.

Jamison Painter
This email originated from outside ECU.

I find it very interesting that that people invent month names for calendars that sound artificial and brittle, compared to month names that have the sanctity of time-honoured usage, such as Capricorn, FromSouth 1. I mean, seriously, not only does that LOOK awkward, it even SOUNDS awkward! For Heaven's sake, if you are going to invent something new, at LEAST try to make it sound pleasant to the ears, and try to make it come off the tongue mellifluously. 

Although the FRC perhaps had things about it that made its continued use impractical (the fact that the month and day names were designed to be compatible with the Île-de-France region in particular, thus rendering its use outside of Metropolitan France impractical [this issue even presenting a problem in French colonial possessions, let alone anywhere else]), at least the month and day names were lovely, and evocative of an ideal life, acknowledging the very real fact that the primary purpose of a calendar is to know when to plant, when to sow, when to reap, and essentially, to know as much about agriculture as possible. Even today, we can see that the continued success of Farmer's Almanacs, even among city-folk, is proof that the point of a calendar is for agriculture and knowledge of the seasons, and the weather that goes along with them.

Then again, when it comes to MICHAEL O, I have more or less given up hope of anything intelligent issuing forth from his brain. Someone who (a), cannot spell a simple name like "Jamison" correctly, even though I sign off with it with every post, and (b), doesn't seem to understand the concept of four seasons (no, I have NOT forgotten the argument you made trying to indicate that we could declare the seasons to start before or after they in fact do [the Equinoxes and the Solstices]), can't be expected to offer much to a discussion. I suspect very strongly that if this list were moderated he probably would have been booted long ago for (a), being a troll, (b), insulting others gratuitously, and making them leave the list, and (c), for then getting offended when he is subjected to same treatment. 

Of course, I DO have a few ideas re: how one could make the FRC usable world-wide. The first thing would be to acknowledge that the Complimentary Days, and the Festivals for them, are worthy of being celebrated world-wide. However, the sixth day, which is Leap Day, Festival of the Revolution (in France), could serve for other nations as a National Day specific to their own country.

As for the names of the months and the days of the year, where the existing ones work well, they should be retained (a good portion of the USA would fit into this category). But where the seasons and weather are different, especially such that different food grows at various times, the months could be renamed (still using the concept of neo-logisms from the French and Latin), and the day names could be changed. 

The FRC is a good calendar. It is by far better than the Gregorian Calendar, and more accurate, at least when calculations for Leap Year are made based on when the Autumnal Equinox occurs in Paris. For that matter, the von Mädler rules are more accurate than Gregory's rules are. To be fair, one could apply the von Mädler rules to our existing calendar.

Of course, I shall be asked how the FRC is better than the Gregorian or other calendars. The first way it is better is in terms of calculating Leap Years, as demonstrated above. Secondly, the more logical Decimal "week", with every month having precisely 30 days, means that one never has to buy a new calendar, at least not until the existing one wears out. Thirdly, the FRC is centered on agriculture. If one lives in or near a territory with weather like the Île-de-France region, when a day comes up, the food for that day is generally in season. Again, for other regions, the days could be renamed. Fourthly, the months quite correctly predict the weather. Again, for other regions, the months could be renamed. 

So there you have it. My calendar recommendation in a nut-shell. I am sure many of you also have excellent ideas, and it is interesting to read them.

Jamison E. Painter, MA 

3 Pluviôse CCXXVIII, Butcher's Broom

On Wed, Jan 22, 2020, 7:34 AM Michael Ossipoff <[hidden email]> wrote:
This email originated from outside ECU.

Walter--

Yes, Capricorn, FromSouth1,rounds to 29 days. Though none of the ecliptic-months round to 32 days, one of them, Cancer, FromNorth1, is nearly 31.5 days. 

I'm pleased to hear that the Iranian Calendar gave Capricorn, FromSouth1, 29 days, as I do.

Cancer, FromNorth1, is the ecliptic-month that comes closest to rounding up, and that would put it to 32 days, so there's justification for their giving it the extra day, or the leapday, and making it 32 days.

...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year.

5 W
Aquarius 3rd
January 22nd, 2020
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Re: Eclipic accuracy instead of uniform familiar month-lengths

k.palmen@btinternet.com
In reply to this post by Michael Ossipoff
This email originated from outside ECU.

Dear Michael, Walter and Calendar People


Michael said

"...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year."


I'm not sure that this is actually true in practice. One would need to measure the month starts against their corresponding ecliptic longitudes to verify this. The main advantage of have the leap day at the end of the year is in calendar calculations. In particular, the day of year number of any date is the same every year.


I see Micheal refers to an extra day. Why does Micheal think this is necessary?



Karl


Thursday Delta January 2020




------ Original Message ------
From: "Michael Ossipoff" <[hidden email]>
To: [hidden email]
Sent: Wednesday, 22 Jan, 2020 At 13:33
Subject: Re: Eclipic accuracy instead of uniform familiar month-lengths

This email originated from outside ECU.

Walter--

Yes, Capricorn, FromSouth1,rounds to 29 days. Though none of the ecliptic-months round to 32 days, one of them, Cancer, FromNorth1, is nearly 31.5 days.

I'm pleased to hear that the Iranian Calendar gave Capricorn, FromSouth1, 29 days, as I do.

Cancer, FromNorth1, is the ecliptic-month that comes closest to rounding up, and that would put it to 32 days, so there's justification for their giving it the extra day, or the leapday, and making it 32 days.

...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year.

5 W
Aquarius 3rd
January 22nd, 2020
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Re: Eclipic accuracy instead of uniform familiar month-lengths

Walter J Ziobro
In reply to this post by Michael Ossipoff
This email originated from outside ECU.

Dear Karl

Good point The Iranians don't have an "extra day" in leap year They just recalculate the month lengths every year

WalterZiobro




On Thursday, January 23, 2020 k.palmen <[hidden email]> wrote:

This email originated from outside ECU.

Dear Michael, Walter and Calendar People


Michael said

"...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year."


I'm not sure that this is actually true in practice. One would need to measure the month starts against their corresponding ecliptic longitudes to verify this. The main advantage of have the leap day at the end of the year is in calendar calculations. In particular, the day of year number of any date is the same every year.


I see Micheal refers to an extra day. Why does Micheal think this is necessary?



Karl


Thursday Delta January 2020




------ Original Message ------
From: "Michael Ossipoff" <[hidden email]>
To: [hidden email]
Sent: Wednesday, 22 Jan, 2020 At 13:33
Subject: Re: Eclipic accuracy instead of uniform familiar month-lengths

This email originated from outside ECU.

Walter--

Yes, Capricorn, FromSouth1,rounds to 29 days. Though none of the ecliptic-months round to 32 days, one of them, Cancer, FromNorth1, is nearly 31.5 days.

I'm pleased to hear that the Iranian Calendar gave Capricorn, FromSouth1, 29 days, as I do.

Cancer, FromNorth1, is the ecliptic-month that comes closest to rounding up, and that would put it to 32 days, so there's justification for their giving it the extra day, or the leapday, and making it 32 days.

...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year.

5 W
Aquarius 3rd
January 22nd, 2020
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Re: Eclipic accuracy instead of uniform familiar month-lengths

k.palmen@btinternet.com
This email originated from outside ECU.

Dear Walter, Michael and Calendar People


The "extra day" is in addition to the leap day. The Iranian calendar does have leap day, which occurs at the end of the year whenever necessary to ensure the following year begins on the correct day. It has no extra day.


I want Michael to explain why he has this extra day, to make that issue clear to the list. Walter's reply shows that this is necessary.


Karl


Friday Delta January 2020




------ Original Message ------
From: "Walter J Ziobro" <[hidden email]>
To: [hidden email]
Sent: Thursday, 23 Jan, 2020 At 18:04
Subject: Re: Eclipic accuracy instead of uniform familiar month-lengths

This email originated from outside ECU.

Dear Karl

Good point The Iranians don't have an "extra day" in leap year They just recalculate the month lengths every year

WalterZiobro




On Thursday, January 23, 2020 k.palmen <[hidden email]> wrote:

This email originated from outside ECU.

Dear Michael, Walter and Calendar People


Michael said

"...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year."


I'm not sure that this is actually true in practice. One would need to measure the month starts against their corresponding ecliptic longitudes to verify this. The main advantage of have the leap day at the end of the year is in calendar calculations. In particular, the day of year number of any date is the same every year.


I see Micheal refers to an extra day. Why does Micheal think this is necessary?



Karl


Thursday Delta January 2020

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Re: Eclipic accuracy instead of uniform familiar month-lengths

Michael Ossipoff
In reply to this post by k.palmen@btinternet.com
This email originated from outside ECU.

Karl said:
.
Michael said
.
"...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year."
.
Karl said:
.
I'm not sure that this is actually true in practice. One would need to measure the month starts against their corresponding ecliptic longitudes to verify this.
.
No.  What Karl suggests above is one approach, but definitely not the only one.
.
In fact, it doesn't work well. Trying to define the month-system by the correspondence between calendrical month-starts and astronomical ecliptic-month-starts gives different results in different years.  It gives different results when the calendar-date is defined with respect to different longitudes.
.
Whereas, defining the system by 1) yearstart rule; an 2) month-lengths is consistently universally applicable, by year and by longitude.
.
Yes, I considered the approach that Karl suggests, and rejected it for the reason stated above.
.
Karl continued:
.
The main advantage of have the leap day at the end of the year is in calendar calculations. In particular, the day of year number of any date is the same every year.
.
...and, additionally, as I said, the exra day and the leapday don't cause any error other than in the last day or two of the year.
.
Karl continues:
.
I see Micheal refers to an extra day. Why does Micheal think this is necessary?
.
Because, when the lengths of the actual astronomical ecliptic-months are rounded to the nearest day, they only add up to 364.
.
I wanted a common-year to have 365 days (as did the designers of the Indian National Calendar), and so I add an extra day to one of the calendrical-months.   i.e. I give to one of the calendrical-months, in common-years, a day more than the number that its corresponding astronomical ecliptic-month rounds to.   (...as did the designers of the Indian National Calendar.)
.
5 F
Aquarius 5th
January 24th
.
Michael Ossipoff

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Re: Eclipic accuracy instead of uniform familiar month-lengths

Michael Ossipoff
In reply to this post by Walter J Ziobro
This email originated from outside ECU.



On Thu, Jan 23, 2020 at 1:04 PM Walter J Ziobro <[hidden email]> wrote:
This email originated from outside ECU.

Dear Karl

Good point The Iranians don't have an "extra day" in leap year They just recalculate the month lengths every year

WalterZiobro

South-Solstice Ecliptic-Months doesn't have an explicit leapyear or leapday. It uses the Nearest-Day yearstart rule:  The calendar year starts on the day that starts closest to the South-Solstice.

That automatically, not explicitly, makes some years a day longer. They're the leapyears.

But, with many calendars, there will be (at least effective, if not explicitly-designated) leapyears that are a day (or a week) longer than usual.

5 F
Aquarius 5th
January 24th, 2020

Michael Ossipoff


 



On Thursday, January 23, 2020 k.palmen <[hidden email]> wrote:

This email originated from outside ECU.

Dear Michael, Walter and Calendar People


Michael said

"...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year."


I'm not sure that this is actually true in practice. One would need to measure the month starts against their corresponding ecliptic longitudes to verify this. The main advantage of have the leap day at the end of the year is in calendar calculations. In particular, the day of year number of any date is the same every year.


I see Micheal refers to an extra day. Why does Micheal think this is necessary?



Karl


Thursday Delta January 2020




------ Original Message ------
From: "Michael Ossipoff" <[hidden email]>
To: [hidden email]
Sent: Wednesday, 22 Jan, 2020 At 13:33
Subject: Re: Eclipic accuracy instead of uniform familiar month-lengths

This email originated from outside ECU.

Walter--

Yes, Capricorn, FromSouth1,rounds to 29 days. Though none of the ecliptic-months round to 32 days, one of them, Cancer, FromNorth1, is nearly 31.5 days.

I'm pleased to hear that the Iranian Calendar gave Capricorn, FromSouth1, 29 days, as I do.

Cancer, FromNorth1, is the ecliptic-month that comes closest to rounding up, and that would put it to 32 days, so there's justification for their giving it the extra day, or the leapday, and making it 32 days.

...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year.

5 W
Aquarius 3rd
January 22nd, 2020
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Re: Eclipic accuracy instead of uniform familiar month-lengths

k.palmen@btinternet.com
In reply to this post by Michael Ossipoff
This email originated from outside ECU.

Dear Michael and Calendar People


Thank you Michael for your reply.


I asked Michael why he thinks the extra day is necessary. Here is his reply:


Because, when the lengths of the actual astronomical ecliptic-months are rounded to the nearest day, they only add up to 364.


A better way would be to round the first astronomical ecliptic-month, the first two, first three, etc. up to the whole year, which of course rounds to 365 days and so no extra day is needed, only an occasional leap day. The number of days in the individual months can of course be obtained by taking the differences.


The month starts are then close to the corresponding ecliptic-month starts, whereas Michael's method would cause some later months to start early. If the new year is within half a day of the March equinox (like in the Iranian Calendar), every subsequent month would start within one day of corresponding ecliptic-month start every year.


Karl


Saturday Delta January 2020




------ Original Message ------
From: "Michael Ossipoff" <[hidden email]>
To: [hidden email]
Sent: Friday, 24 Jan, 2020 At 21:15
Subject: Re: Eclipic accuracy instead of uniform familiar month-lengths

This email originated from outside ECU.

Karl said:
.
Michael said
.
"...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year."
.
Karl said:
.
I'm not sure that this is actually true in practice. One would need to measure the month starts against their corresponding ecliptic longitudes to verify this.
.
No. What Karl suggests above is one approach, but definitely not the only one.
.
In fact, it doesn't work well. Trying to define the month-system by the correspondence between calendrical month-starts and astronomical ecliptic-month-starts gives different results in different years. It gives different results when the calendar-date is defined with respect to different longitudes.
.
Whereas, defining the system by 1) yearstart rule; an 2) month-lengths is consistently universally applicable, by year and by longitude.
.
Yes, I considered the approach that Karl suggests, and rejected it for the reason stated above.
.
Karl continued:
.
The main advantage of have the leap day at the end of the year is in calendar calculations. In particular, the day of year number of any date is the same every year.
.
...and, additionally, as I said, the exra day and the leapday don't cause any error other than in the last day or two of the year.
.
Karl continues:
.
I see Micheal refers to an extra day. Why does Micheal think this is necessary?
.
Because, when the lengths of the actual astronomical ecliptic-months are rounded to the nearest day, they only add up to 364.
.
I wanted a common-year to have 365 days (as did the designers of the Indian National Calendar), and so I add an extra day to one of the calendrical-months. i.e. I give to one of the calendrical-months, in common-years, a day more than the number that its corresponding astronomical ecliptic-month rounds to. (...as did the designers of the Indian National Calendar.)
.
5 F
Aquarius 5th
January 24th
.
Michael Ossipoff

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Re: Eclipic accuracy instead of uniform familiar month-lengths

Walter J Ziobro
In reply to this post by Michael Ossipoff
This email originated from outside ECU.

Dear Karl and Michael

If I am not mistaken, isn't it the case that the position of the moon will also cause the earth to reach an ecliptic degree sooner in some months than others? Doesn't this partly explain why the distribution of short and long months in the Iranian calendar is uneven? Unless you are going to approximate the ecliptic month lengths, as in the Indian calendar, you are going to have to astronomically recalculate the month lengths every year, as in the Iranian and Chinese solar term calendars

WalterZiobro




On Saturday, January 25, 2020 k.palmen <[hidden email]> wrote:

This email originated from outside ECU.

Dear Michael and Calendar People


Thank you Michael for your reply.


I asked Michael why he thinks the extra day is necessary. Here is his reply:


Because, when the lengths of the actual astronomical ecliptic-months are rounded to the nearest day, they only add up to 364.


A better way would be to round the first astronomical ecliptic-month, the first two, first three, etc. up to the whole year, which of course rounds to 365 days and so no extra day is needed, only an occasional leap day. The number of days in the individual months can of course be obtained by taking the differences.


The month starts are then close to the corresponding ecliptic-month starts, whereas Michael's method would cause some later months to start early. If the new year is within half a day of the March equinox (like in the Iranian Calendar), every subsequent month would start within one day of corresponding ecliptic-month start every year.


Karl


Saturday Delta January 2020




------ Original Message ------
From: "Michael Ossipoff" <[hidden email]>
To: [hidden email]
Sent: Friday, 24 Jan, 2020 At 21:15
Subject: Re: Eclipic accuracy instead of uniform familiar month-lengths

This email originated from outside ECU.

Karl said:
.
Michael said
.
"...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year."
.
Karl said:
.
I'm not sure that this is actually true in practice. One would need to measure the month starts against their corresponding ecliptic longitudes to verify this.
.
No. What Karl suggests above is one approach, but definitely not the only one.
.
In fact, it doesn't work well. Trying to define the month-system by the correspondence between calendrical month-starts and astronomical ecliptic-month-starts gives different results in different years. It gives different results when the calendar-date is defined with respect to different longitudes.
.
Whereas, defining the system by 1) yearstart rule; an 2) month-lengths is consistently universally applicable, by year and by longitude.
.
Yes, I considered the approach that Karl suggests, and rejected it for the reason stated above.
.
Karl continued:
.
The main advantage of have the leap day at the end of the year is in calendar calculations. In particular, the day of year number of any date is the same every year.
.
...and, additionally, as I said, the exra day and the leapday don't cause any error other than in the last day or two of the year.
.
Karl continues:
.
I see Micheal refers to an extra day. Why does Micheal think this is necessary?
.
Because, when the lengths of the actual astronomical ecliptic-months are rounded to the nearest day, they only add up to 364.
.
I wanted a common-year to have 365 days (as did the designers of the Indian National Calendar), and so I add an extra day to one of the calendrical-months. i.e. I give to one of the calendrical-months, in common-years, a day more than the number that its corresponding astronomical ecliptic-month rounds to. (...as did the designers of the Indian National Calendar.)
.
5 F
Aquarius 5th
January 24th
.
Michael Ossipoff

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Re: Eclipic accuracy instead of uniform familiar month-lengths

k.palmen@btinternet.com
This email originated from outside ECU.

Dear Walter, Michael and Calendar People


I know the planets advance or delay the equinoxes and solstices by a few minutes. This can be seen by subtracting a year's displacement from an equinox or solstice time for a few consecutive years. I remember doing this on this list.


These fluctuations of a few minutes, become an issue only when the fractional part rounded is near a half. Then the slow long term changes could also change the result.


I expect the figures used by Michael are averages over several years, but they could be from just one year.


This raises the issue of where Michael got his figures from. I have not found any webpage that tells me when the sun reaches a given ecliptic longitude or just the 12 ecliptic longitudes a multiple of 30 degrees, which form the start & ends of the ecliptic-months (also known in the Chinese calendar as principal terms). If any calendar person knows of such a website, they could let gives us a link to it. Also I'd appreciate Michael letting us know about his figures.


Sunday Delta January 2020


Karl




------ Original Message ------
From: "Walter J Ziobro" <[hidden email]>
To: [hidden email]
Sent: Saturday, 25 Jan, 2020 At 11:46
Subject: Re: Eclipic accuracy instead of uniform familiar month-lengths

This email originated from outside ECU.

Dear Karl and Michael

If I am not mistaken, isn't it the case that the position of the moon will also cause the earth to reach an ecliptic degree sooner in some months than others? Doesn't this partly explain why the distribution of short and long months in the Iranian calendar is uneven? Unless you are going to approximate the ecliptic month lengths, as in the Indian calendar, you are going to have to astronomically recalculate the month lengths every year, as in the Iranian and Chinese solar term calendars

WalterZiobro




On Saturday, January 25, 2020 k.palmen <[hidden email]> wrote:

This email originated from outside ECU.

Dear Michael and Calendar People


Thank you Michael for your reply.


I asked Michael why he thinks the extra day is necessary. Here is his reply:


Because, when the lengths of the actual astronomical ecliptic-months are rounded to the nearest day, they only add up to 364.


A better way would be to round the first astronomical ecliptic-month, the first two, first three, etc. up to the whole year, which of course rounds to 365 days and so no extra day is needed, only an occasional leap day. The number of days in the individual months can of course be obtained by taking the differences.


The month starts are then close to the corresponding ecliptic-month starts, whereas Michael's method would cause some later months to start early. If the new year is within half a day of the March equinox (like in the Iranian Calendar), every subsequent month would start within one day of corresponding ecliptic-month start every year.


Karl


Saturday Delta January 2020




------ Original Message ------
From: "Michael Ossipoff" <[hidden email]>
To: [hidden email]
Sent: Friday, 24 Jan, 2020 At 21:15
Subject: Re: Eclipic accuracy instead of uniform familiar month-lengths

This email originated from outside ECU.

Karl said:
.
Michael said
.
"...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year."
.
Karl said:
.
I'm not sure that this is actually true in practice. One would need to measure the month starts against their corresponding ecliptic longitudes to verify this.
.
No. What Karl suggests above is one approach, but definitely not the only one.
.
In fact, it doesn't work well. Trying to define the month-system by the correspondence between calendrical month-starts and astronomical ecliptic-month-starts gives different results in different years. It gives different results when the calendar-date is defined with respect to different longitudes.
.
Whereas, defining the system by 1) yearstart rule; an 2) month-lengths is consistently universally applicable, by year and by longitude.
.
Yes, I considered the approach that Karl suggests, and rejected it for the reason stated above.
.
Karl continued:
.
The main advantage of have the leap day at the end of the year is in calendar calculations. In particular, the day of year number of any date is the same every year.
.
...and, additionally, as I said, the exra day and the leapday don't cause any error other than in the last day or two of the year.
.
Karl continues:
.
I see Micheal refers to an extra day. Why does Micheal think this is necessary?
.
Because, when the lengths of the actual astronomical ecliptic-months are rounded to the nearest day, they only add up to 364.
.
I wanted a common-year to have 365 days (as did the designers of the Indian National Calendar), and so I add an extra day to one of the calendrical-months. i.e. I give to one of the calendrical-months, in common-years, a day more than the number that its corresponding astronomical ecliptic-month rounds to. (...as did the designers of the Indian National Calendar.)
.
5 F
Aquarius 5th
January 24th
.
Michael Ossipoff

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Re: Eclipic accuracy instead of uniform familiar month-lengths

Amos Shapir-2
This email originated from outside ECU.

Hi Karl and calendar people,

I get all the information I need of the Sun, Moon and planets from horizons.jpl.nasa.gov .
Its interface is terribly ancient (it needs TELNET connection for full functionality) but it really has more that you'd ever need to calculate positions of solar system bodies.

On Sun, Jan 26, 2020 at 12:53 PM [hidden email] <[hidden email]> wrote:
This email originated from outside ECU.

Dear Walter, Michael and Calendar People


I know the planets advance or delay the equinoxes and solstices by a few minutes. This can be seen by subtracting a year's displacement from an equinox or solstice time for a few consecutive years. I remember doing this on this list.


These fluctuations of a few minutes, become an issue only when the fractional part rounded is near a half. Then the slow long term changes could also change the result.


I expect the figures used by Michael are averages over several years, but they could be from just one year.


This raises the issue of where Michael got his figures from. I have not found any webpage that tells me when the sun reaches a given ecliptic longitude or just the 12 ecliptic longitudes a multiple of 30 degrees, which form the start & ends of the ecliptic-months (also known in the Chinese calendar as principal terms). If any calendar person knows of such a website, they could let gives us a link to it. Also I'd appreciate Michael letting us know about his figures.


Sunday Delta January 2020


Karl


--
Amos Shapir
 
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Re: Eclipic accuracy instead of uniform familiar month-lengths

Michael Ossipoff
In reply to this post by k.palmen@btinternet.com
This email originated from outside ECU.



On Sun, Jan 26, 2020 at 5:53 AM [hidden email] <[hidden email]> wrote:
This email originated from outside ECU.

Dear Walter, Michael and Calendar People


I know the planets advance or delay the equinoxes and solstices by a few minutes. This can be seen by subtracting a year's displacement from an equinox or solstice time for a few consecutive years. I remember doing this on this list.


These fluctuations of a few minutes, become an issue only when the fractional part rounded is near a half. Then the slow long term changes could also change the result.


I expect the figures used by Michael are averages over several years, but they could be from just one year.


They're from just one year. But I'll remind you that variations of a few minutes, in the entry of the center of the Sun into the tropical ecliptic-divisions is insignificant when we're talking about rounding to the nearest day.

As for where I found the times for the starts of the astronomical ecliptic-months--I'll look around the Internet and find it again, and will then post where I found it.

The method you suggested for choosing the lengths of the calendrical ecliptic-months amounts to the same as the proposal that you'd earlier made, and my objection to it is the same.

For some particular year, you'd make each calendrical monthstart as close as possible to the correspoinding astronomical monthstart.  The problem with that it it's unstable and arbitrary, and would give differfent results for differrent years and different longitudes in the same year.

Detrermining the lengths of the astronomical ecliptic-months, and rounding to the nearest day is stable and uniform (yes, you mentioned that it can vary by a few minutes).

That isn't surprising, because, if we want month-lengths for the calendrical months, then the most direct source of that is the month-lengths of the astronomical months.

I trust that you weren't suggesting that the calendrical monthlengths be separately designated for each different year, with monthlengths often different in different years.

As soon as I find where I got the astronoimcal ecliptic monthstarts, I'll post it here.

5 Su
Aquarius 7th
January 26th

Michael Ossipoff



This raises the issue of where Michael got his figures from. I have not found any webpage that tells me when the sun reaches a given ecliptic longitude or just the 12 ecliptic longitudes a multiple of 30 degrees, which form the start & ends of the ecliptic-months (also known in the Chinese calendar as principal terms). If any calendar person knows of such a website, they could let gives us a link to it. Also I'd appreciate Michael letting us know about his figures.


Sunday Delta January 2020


Karl




------ Original Message ------
From: "Walter J Ziobro" <[hidden email]>
To: [hidden email]
Sent: Saturday, 25 Jan, 2020 At 11:46
Subject: Re: Eclipic accuracy instead of uniform familiar month-lengths

This email originated from outside ECU.

Dear Karl and Michael

If I am not mistaken, isn't it the case that the position of the moon will also cause the earth to reach an ecliptic degree sooner in some months than others? Doesn't this partly explain why the distribution of short and long months in the Iranian calendar is uneven? Unless you are going to approximate the ecliptic month lengths, as in the Indian calendar, you are going to have to astronomically recalculate the month lengths every year, as in the Iranian and Chinese solar term calendars

WalterZiobro




On Saturday, January 25, 2020 k.palmen <[hidden email]> wrote:

This email originated from outside ECU.

Dear Michael and Calendar People


Thank you Michael for your reply.


I asked Michael why he thinks the extra day is necessary. Here is his reply:


Because, when the lengths of the actual astronomical ecliptic-months are rounded to the nearest day, they only add up to 364.


A better way would be to round the first astronomical ecliptic-month, the first two, first three, etc. up to the whole year, which of course rounds to 365 days and so no extra day is needed, only an occasional leap day. The number of days in the individual months can of course be obtained by taking the differences.


The month starts are then close to the corresponding ecliptic-month starts, whereas Michael's method would cause some later months to start early. If the new year is within half a day of the March equinox (like in the Iranian Calendar), every subsequent month would start within one day of corresponding ecliptic-month start every year.


Karl


Saturday Delta January 2020




------ Original Message ------
From: "Michael Ossipoff" <[hidden email]>
To: [hidden email]
Sent: Friday, 24 Jan, 2020 At 21:15
Subject: Re: Eclipic accuracy instead of uniform familiar month-lengths

This email originated from outside ECU.

Karl said:
.
Michael said
.
"...though I prefer to give the extra day and the leapday to the last month of the year, to maimize ecliptic-accuracy except in the last day or two of the year."
.
Karl said:
.
I'm not sure that this is actually true in practice. One would need to measure the month starts against their corresponding ecliptic longitudes to verify this.
.
No. What Karl suggests above is one approach, but definitely not the only one.
.
In fact, it doesn't work well. Trying to define the month-system by the correspondence between calendrical month-starts and astronomical ecliptic-month-starts gives different results in different years. It gives different results when the calendar-date is defined with respect to different longitudes.
.
Whereas, defining the system by 1) yearstart rule; an 2) month-lengths is consistently universally applicable, by year and by longitude.
.
Yes, I considered the approach that Karl suggests, and rejected it for the reason stated above.
.
Karl continued:
.
The main advantage of have the leap day at the end of the year is in calendar calculations. In particular, the day of year number of any date is the same every year.
.
...and, additionally, as I said, the exra day and the leapday don't cause any error other than in the last day or two of the year.
.
Karl continues:
.
I see Micheal refers to an extra day. Why does Micheal think this is necessary?
.
Because, when the lengths of the actual astronomical ecliptic-months are rounded to the nearest day, they only add up to 364.
.
I wanted a common-year to have 365 days (as did the designers of the Indian National Calendar), and so I add an extra day to one of the calendrical-months. i.e. I give to one of the calendrical-months, in common-years, a day more than the number that its corresponding astronomical ecliptic-month rounds to. (...as did the designers of the Indian National Calendar.)
.
5 F
Aquarius 5th
January 24th
.
Michael Ossipoff

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Re: Eclipic accuracy instead of uniform familiar month-lengths

k.palmen@btinternet.com
In reply to this post by Amos Shapir-2
This email originated from outside ECU.

Dear Amos and Calendar People


Thank you for the web page. I access the web interface and found that it's not quite what I wanted. I wanted the times the the sun reaches a certain ecliptic longitude, especially the multiples of 30 degrees. Here I assume the R.A. is the ecliptic longitude in hours (difference between sidereal and solar time). I remember finding another such page.


Karl


Monday Alpha February 2020




------ Original Message ------
From: "Amos Shapir" <[hidden email]>
To: [hidden email]
Sent: Sunday, 26 Jan, 2020 At 15:14
Subject: Re: Eclipic accuracy instead of uniform familiar month-lengths

This email originated from outside ECU.

Hi Karl and calendar people,

I get all the information I need of the Sun, Moon and planets from horizons.jpl.nasa.gov .
Its interface is terribly ancient (it needs TELNET connection for full functionality) but it really has more that you'd ever need to calculate positions of solar system bodies.

On Sun, Jan 26, 2020 at 12:53 PM [hidden email] <[hidden email]> wrote:
This email originated from outside ECU.

Dear Walter, Michael and Calendar People


I know the planets advance or delay the equinoxes and solstices by a few minutes. This can be seen by subtracting a year's displacement from an equinox or solstice time for a few consecutive years. I remember doing this on this list.


These fluctuations of a few minutes, become an issue only when the fractional part rounded is near a half. Then the slow long term changes could also change the result.


I expect the figures used by Michael are averages over several years, but they could be from just one year.


This raises the issue of where Michael got his figures from. I have not found any webpage that tells me when the sun reaches a given ecliptic longitude or just the 12 ecliptic longitudes a multiple of 30 degrees, which form the start & ends of the ecliptic-months (also known in the Chinese calendar as principal terms). If any calendar person knows of such a website, they could let gives us a link to it. Also I'd appreciate Michael letting us know about his figures.


Sunday Delta January 2020


Karl


--
Amos Shapir
123