Solar Calendar Accuracy RE: New Henry-Hanke calendar/website, old shortcomings

classic Classic list List threaded Threaded
4 messages Options
Reply | Threaded
Open this post in threaded view
|

Solar Calendar Accuracy RE: New Henry-Hanke calendar/website, old shortcomings

Karl Palmen

Dear Michael, Irv and Calendar People

 

I see a difference of opinion between Irv and Michael over the type of accuracy to be aimed for by a solar calendar, especially a leap week calendar.

 

Irv has expressed the opinion that the mean year should be very near a tropical year beginning at a chosen equinox and solstice and prefers the March equinox or June solstice because either tropical year in days will change little in the next few thousand years. This preference implies that Irv would not use the same equinox or solstice throughout an entire precession cycle (Michael has brought up this issue).

 

Michael has expressed the opinion that the mean year should be very near the mean tropical year so that all ecliptic longitudes would be treated equally, but may consider the June solstice, because this will change little in the next ten thousand years.

 

My opinion is that for a civil calendar, especially a leap week calendar, it is sufficient that the mean year lies within the range of tropical years. Then the mean year is very near the tropical year for some unspecified ecliptic longitude. Irv has called such an ecliptic longitude a calendar season. Only when calendar mean year approaches the edge of the range, is it changed.  I would not support any additional complication to bring a civil calendar beyond this to either Irv’s or Michael’s aim.

 

Karl

 

16(05(12

 

From: East Carolina University Calendar discussion List [mailto:[hidden email]] On Behalf Of Michael Ossipoff
Sent: 09 January 2017 03:59
To: [hidden email]
Subject: Re: New Henry-Hanke calendar/website, old shortcomings

 

 

 

On Sun, Jan 8, 2017 at 6:40 PM, Irv Bromberg <[hidden email]> wrote:

From: East Carolina University Calendar discussion List [[hidden email]] on behalf of Michael Ossipoff [[hidden email]]

Sent: Sunday, January 08, 2017 17:25

 

I'd said:
 

 

But my main point was that year-round accuracy is more practical, and probably better for public acceptability, rather than calendar-stability about one particular ecliptic point.

 

...and that using the mean of the March & September equinoxes doesn't result in serious displacements over the long cycle of back-&-forth tropical-year-length drift.

Bromberg replies:

With regard to what Ossipoff is calling "year-round accuracy", note that I've been there, done that

 

That's great. Why you aren't still there, and are now doing something else, is your business, and none of my business.

Suit yourself.

immune to this drift because it explicitly uses the contemporaneously most accurate Delta T adjustment.


Even though I developed MOY and RAY, I don't particularly promote them, because I became convinced that it is better to use a simple fixed arithmetic leap rule to approximate the mean north solstitial year or the mean northward equinoctial year. Note also that when I detailed them in this CALNDR LISTSERV, they were met by severe criticism, which is why I practically abandoned them -- so I'm surprised that the same critics haven't been blasting you with similar remarks. Possibly it is because my description was very detailed, but yours has been consistently vague?

 

Do you realize that you're being vague now? If you want to say that something that I said was vague or unclear in meaning, then you need to specify what statement of mine you're referring to, and in what way it lacks meaning.

Otherwise it's just more of your usual vague, unsupported, nonspecific, referentless angry noises.

If you think that there's a valid criticism of, or objection to, using the mean tropical year, for the purpose of year-round accuracy (or maybe using the mean of the March equinox year & the September equinox year), then you need to say so. Otherwise we have no way of knowing what you're trying to say.


As an example of Ossipoff's vagueness, I have no idea what he means by "the mean of the March & September equinoxes",

 

No, I spoke of the mean of the March equinox year and the September equinox year.

Because that was said in the context of discussion of the choice of reference-tropical-year, for choosing the value of Y, then it should be obvious that I was referring to the mean of the lengths of the March equinox year and the September equinox year.



 

but anyway he persists in asserting that it "doesn't result in serious displacements over the long cycle of back-&-forth tropical-year-length drift" even though he hasn't evaluated or demonstrated the veracity of that claim in any way.

 

Don't worry about it.

If the use (for Y in my leapyear-rule) of the length of the mean tropical year, or the use of the mean of the lengths of the September equinox year & the March equinox year, would cause a problematic amount of periodic calendar-displacement over the long cycle of back-&-forth tropical-year-length drift, then your use of the June solstice year or the March equinox year would result in an even greater maximum displacement, measured throughout the year (instead of only at the June solstice or March equinox).

Yes, you don't propose using the March equinox year or the June solstice year over the entire (20,000 year?--I haven't looked at the graphs for a while) cycle of tropical-year length-changes that your graphs imply. But, even during the time that you would propose using one of those as the RTY, the result would be more maximum accumulated calendar-displacement (where that maximum is the maximum of calendar-displacements observed at all times of year), compared to what it would be with the mean tropical year as the RTY, or with the mean of the September equinox year's length and the March equinox year's length as the Y value..

 

As for the magnitude of the displacement over that long year-length-drift cycle, it was some time ago when I calculated it (based on your tropical-year-length graphs). So, right now I couldn't tell you what that magnitude was.

It wasn't much. A few days? I don't know. But, considering that it represents the extremes of a cycle with a period of 10,000 or 20,000 years or something, it didn't seem much at all.

The back & forth accumulated calendar-displacements, resulting from the ongoing tropical-year-length changes over each 10,000 years or so, are somewhat less each time (over the next several tens of thousands of years), according to your graphs. I mention that only so that you won't crow that I believed otherwise.

 

It wasn't very much. But, as I said, the amount doesn't matter, because the maximum, over all times of year, during that long cycle, is worse when you use the March equinox year or the June solstice year (instead of the mean tropical year,  or the mean of the lengths of the March & September equinox years) as the reference tropical year length for a calendar's leapyear-rule.

When I mentioned that the long-cycle calendar-displacement isn't so great, I didn't mean it as an assertion that I want to convince you of, or as an issue of angry contention. I just mentioned it, that's all. I'd gladly tell you what my estimate of the amount was, but it was some time ago when I calculated it,  and I didn't think that the number would be needed later.

(...and, as I've said, this matter of what the calendar will do over the next 10,000 years isn't of great interest to most people.)

You have a lot of anger, and a strong need to contradict. So much, that it sometimes motivates you to contradict, even when doing so requires you to say something that's obviously, blatantly, wrong. There have been several instances of that, and I've called attention to each when it happened.

Always, it's your anger, usually in the form of vague, nonspecific angry noises.  ...when not in the form of outright incorrect statements.

I have no idea why you have that anger and that need. I have no idea why you can't disagree  politely.  ...or why you can't behave peacefully, why you need to rage. That's none of my business.

Michael Ossipoff


 


-- Irv Bromberg, University of Toronto, Canada

http://www.sym454.org/seasons/

 

Reply | Threaded
Open this post in threaded view
|

Re: Solar Calendar Accuracy RE: New Henry-Hanke calendar/website, old shortcomings

Walter J Ziobro

Dear Karl and Calendar List

I think that I have mentioned this before, but it's possible with a leap week calendar to place the leap week at the end of the quarter in which the aphelion occurs to keep the relative lengths of the quarters close to the seasonal lengths The leap week could be shifted to the following quarter about once every 5200 years in the current precession era

Walter Ziobro

Sent from AOL Mobile Mail




On Monday, January 9, 2017 Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv and Calendar People

 

I see a difference of opinion between Irv and Michael over the type of accuracy to be aimed for by a solar calendar, especially a leap week calendar.

 

Irv has expressed the opinion that the mean year should be very near a tropical year beginning at a chosen equinox and solstice and prefers the March equinox or June solstice because either tropical year in days will change little in the next few thousand years. This preference implies that Irv would not use the same equinox or solstice throughout an entire precession cycle (Michael has brought up this issue).

 

Michael has expressed the opinion that the mean year should be very near the mean tropical year so that all ecliptic longitudes would be treated equally, but may consider the June solstice, because this will change little in the next ten thousand years.

 

My opinion is that for a civil calendar, especially a leap week calendar, it is sufficient that the mean year lies within the range of tropical years. Then the mean year is very near the tropical year for some unspecified ecliptic longitude. Irv has called such an ecliptic longitude a calendar season. Only when calendar mean year approaches the edge of the range, is it changed.  I would not support any additional complication to bring a civil calendar beyond this to either Irv’s or Michael’s aim.

 

Karl

 

16(05(12

 

From: East Carolina University Calendar discussion List [mailto:CALNDR-L@...] On Behalf Of Michael Ossipoff
Sent: 09 January 2017 03:59
To: CALNDR-L@...
Subject: Re: New Henry-Hanke calendar/website, old shortcomings

 

 

 

On Sun, Jan 8, 2017 at 6:40 PM, Irv Bromberg <[hidden email]> wrote:

From: East Carolina University Calendar discussion List [[hidden email]] on behalf of Michael Ossipoff [[hidden email]]

Sent: Sunday, January 08, 2017 17:25

 

I'd said:
 

 

But my main point was that year-round accuracy is more practical, and probably better for public acceptability, rather than calendar-stability about one particular ecliptic point.

 

...and that using the mean of the March & September equinoxes doesn't result in serious displacements over the long cycle of back-&-forth tropical-year-length drift.

Bromberg replies:

With regard to what Ossipoff is calling "year-round accuracy", note that I've been there, done that

 

That's great. Why you aren't still there, and are now doing something else, is your business, and none of my business.

Suit yourself.

immune to this drift because it explicitly uses the contemporaneously most accurate Delta T adjustment.


Even though I developed MOY and RAY, I don't particularly promote them, because I became convinced that it is better to use a simple fixed arithmetic leap rule to approximate the mean north solstitial year or the mean northward equinoctial year. Note also that when I detailed them in this CALNDR LISTSERV, they were met by severe criticism, which is why I practically abandoned them -- so I'm surprised that the same critics haven't been blasting you with similar remarks. Possibly it is because my description was very detailed, but yours has been consistently vague?

 

Do you realize that you're being vague now? If you want to say that something that I said was vague or unclear in meaning, then you need to specify what statement of mine you're referring to, and in what way it lacks meaning.

Otherwise it's just more of your usual vague, unsupported, nonspecific, referentless angry noises.

If you think that there's a valid criticism of, or objection to, using the mean tropical year, for the purpose of year-round accuracy (or maybe using the mean of the March equinox year & the September equinox year), then you need to say so. Otherwise we have no way of knowing what you're trying to say.


As an example of Ossipoff's vagueness, I have no idea what he means by "the mean of the March & September equinoxes",

 

No, I spoke of the mean of the March equinox year and the September equinox year.

Because that was said in the context of discussion of the choice of reference-tropical-year, for choosing the value of Y, then it should be obvious that I was referring to the mean of the lengths of the March equinox year and the September equinox year.



 

but anyway he persists in asserting that it "doesn't result in serious displacements over the long cycle of back-&-forth tropical-year-length drift" even though he hasn't evaluated or demonstrated the veracity of that claim in any way.

 

Don't worry about it.

If the use (for Y in my leapyear-rule) of the length of the mean tropical year, or the use of the mean of the lengths of the September equinox year & the March equinox year, would cause a problematic amount of periodic calendar-displacement over the long cycle of back-&-forth tropical-year-length drift, then your use of the June solstice year or the March equinox year would result in an even greater maximum displacement, measured throughout the year (instead of only at the June solstice or March equinox).

Yes, you don't propose using the March equinox year or the June solstice year over the entire (20,000 year?--I haven't looked at the graphs for a while) cycle of tropical-year length-changes that your graphs imply. But, even during the time that you would propose using one of those as the RTY, the result would be more maximum accumulated calendar-displacement (where that maximum is the maximum of calendar-displacements observed at all times of year), compared to what it would be with the mean tropical year as the RTY, or with the mean of the September equinox year's length and the March equinox year's length as the Y value..

 

As for the magnitude of the displacement over that long year-length-drift cycle, it was some time ago when I calculated it (based on your tropical-year-length graphs). So, right now I couldn't tell you what that magnitude was.

It wasn't much. A few days? I don't know. But, considering that it represents the extremes of a cycle with a period of 10,000 or 20,000 years or something, it didn't seem much at all.

The back & forth accumulated calendar-displacements, resulting from the ongoing tropical-year-length changes over each 10,000 years or so, are somewhat less each time (over the next several tens of thousands of years), according to your graphs. I mention that only so that you won't crow that I believed otherwise.

 

It wasn't very much. But, as I said, the amount doesn't matter, because the maximum, over all times of year, during that long cycle, is worse when you use the March equinox year or the June solstice year (instead of the mean tropical year,  or the mean of the lengths of the March & September equinox years) as the reference tropical year length for a calendar's leapyear-rule.

When I mentioned that the long-cycle calendar-displacement isn't so great, I didn't mean it as an assertion that I want to convince you of, or as an issue of angry contention. I just mentioned it, that's all. I'd gladly tell you what my estimate of the amount was, but it was some time ago when I calculated it,  and I didn't think that the number would be needed later.

(...and, as I've said, this matter of what the calendar will do over the next 10,000 years isn't of great interest to most people.)

You have a lot of anger, and a strong need to contradict. So much, that it sometimes motivates you to contradict, even when doing so requires you to say something that's obviously, blatantly, wrong. There have been several instances of that, and I've called attention to each when it happened.

Always, it's your anger, usually in the form of vague, nonspecific angry noises.  ...when not in the form of outright incorrect statements.

I have no idea why you have that anger and that need. I have no idea why you can't disagree  politely.  ...or why you can't behave peacefully, why you need to rage. That's none of my business.

Michael Ossipoff


 


-- Irv Bromberg, University of Toronto, Canada

http://www.sym454.org/seasons/

 

Reply | Threaded
Open this post in threaded view
|

Re: Solar Calendar Accuracy RE: New Henry-Hanke calendar/website, old shortcomings

Karl Palmen

Dear Walter, Michael, Irv and Calendar People

 

I think Walter’s idea is to effectively place the leap week at the quarter-end that is nearest to the aphelion. This I think could reduce the average variation of the ecliptic longitudes with respect to the dates, but not by very much. The amount of reduction would be about the same as for of a leap day calendar the same as this leap week calendar, but instead of a leap week, one has an extra day added to every year at the same place that the leap week would occur, and in a leap year, this is followed by the leap day.

 

This small reduction in the average variation of the ecliptic longitudes with respect to the dates may not be worth the complication of the moving leap week and the leap week not always occurring at the end of the calendar year. It may still be worth thinking about. For a minimum displacement calendar, each quarter could have a different displacement, but I have not figured out how this would work out.

 

Another idea, which could produce a greater reduction is to have a year of 51 ordinary weeks and a moving week, which is located near the aphelion, with leap week at end. Such a year cannot be divided into equal quarters, but could be divided into thirds of 17 weeks each not counting the moving week or leap week. Each third could be divided into 4 months of (5,4,4,4) weeks, the moving week could then be appended to any 4-week month, except the last month of the year, which would receive the leap week.

 

If the effect of the moving week is too strong, the leap week could be placed 6 months away from it (near perihelion) to reduce its effect. Then with (5,4,4,4) weeks, the moving week can only be appended to even-numbered months.

 

Karl

 

16(05(13

 

From: Walter J Ziobro [mailto:[hidden email]]
Sent: 10 January 2017 04:23
To: [hidden email]; Palmen, Karl (STFC,RAL,ISIS)
Subject: RE: Solar Calendar Accuracy RE: New Henry-Hanke calendar/website, old shortcomings

 

Dear Karl and Calendar List

I think that I have mentioned this before, but it's possible with a leap week calendar to place the leap week at the end of the quarter in which the aphelion occurs to keep the relative lengths of the quarters close to the seasonal lengths The leap week could be shifted to the following quarter about once every 5200 years in the current precession era

Walter Ziobro

Sent from AOL Mobile Mail

 


On Monday, January 9, 2017 Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv and Calendar People

 

I see a difference of opinion between Irv and Michael over the type of accuracy to be aimed for by a solar calendar, especially a leap week calendar.

 

Irv has expressed the opinion that the mean year should be very near a tropical year beginning at a chosen equinox and solstice and prefers the March equinox or June solstice because either tropical year in days will change little in the next few thousand years. This preference implies that Irv would not use the same equinox or solstice throughout an entire precession cycle (Michael has brought up this issue).

 

Michael has expressed the opinion that the mean year should be very near the mean tropical year so that all ecliptic longitudes would be treated equally, but may consider the June solstice, because this will change little in the next ten thousand years.

 

My opinion is that for a civil calendar, especially a leap week calendar, it is sufficient that the mean year lies within the range of tropical years. Then the mean year is very near the tropical year for some unspecified ecliptic longitude. Irv has called such an ecliptic longitude a calendar season. Only when calendar mean year approaches the edge of the range, is it changed.  I would not support any additional complication to bring a civil calendar beyond this to either Irv’s or Michael’s aim.

 

Karl

 

16(05(12

Reply | Threaded
Open this post in threaded view
|

Re: Solar Calendar Accuracy RE: New Henry-Hanke calendar/website, old shortcomings

Michael Ossipoff
In reply to this post by Karl Palmen


On Mon, Jan 9, 2017 at 8:27 AM, Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv and Calendar People

 

I see a difference of opinion between Irv and Michael over the type of accuracy to be aimed for by a solar calendar, especially a leap week calendar.

 

Irv has expressed the opinion that the mean year should be very near a tropical year beginning at a chosen equinox and solstice and prefers the March equinox or June solstice because either tropical year in days will change little in the next few thousand years. This preference implies that Irv would not use the same equinox or solstice throughout an entire precession cycle (Michael has brought up this issue).

 

Michael has expressed the opinion that the mean year should be very near the mean tropical year so that all ecliptic longitudes would be treated equally


Yes, it seems best to lower the maximum error throughout the year, because the calendar isn't just for the June solstice, it's for all year.

 

, but may consider the June solstice, because this will change little in the next ten thousand years.


Yes, that has appeal, honoring the June solstice, in recognition of its year's new current era of stability. Practicality isn't everything.

Either would be fine with me.

My main disagreement in that regard, is with the use of the March equinox year, because in the Southern Hemisphere that's the autumnal equinox instead of the vernal equinox. Both solstices are celebrated, but the vernal equinox is celebrated a lot more than the autumnal equinox is. That makes an equinox year an in-egalitarian choice for a calendar's mean year.

 

 

My opinion is that for a civil calendar, especially a leap week calendar, it is sufficient that the mean year lies within the range of tropical years.


Agreed. The tropical years based on solstices & equinoxes only drift, with respect to eachother, by a fraction of a day per millennium.

So it isn't really important which tropical year is used as the calendar's mean year.

Michael Ossipoff


 

Then the mean year is very near the tropical year for some unspecified ecliptic longitude. Irv has called such an ecliptic longitude a calendar season. Only when calendar mean year approaches the edge of the range, is it changed.  I would not support any additional complication to bring a civil calendar beyond this to either Irv’s or Michael’s aim.

 

Karl

 

16(05(12

 

From: East Carolina University Calendar discussion List [mailto:[hidden email]] On Behalf Of Michael Ossipoff
Sent: 09 January 2017 03:59
To: [hidden email]
Subject: Re: New Henry-Hanke calendar/website, old shortcomings

 

 

 

On Sun, Jan 8, 2017 at 6:40 PM, Irv Bromberg <[hidden email]> wrote:

From: East Carolina University Calendar discussion List [[hidden email]] on behalf of Michael Ossipoff [[hidden email]]

Sent: Sunday, January 08, 2017 17:25

 

I'd said:
 

 

But my main point was that year-round accuracy is more practical, and probably better for public acceptability, rather than calendar-stability about one particular ecliptic point.

 

...and that using the mean of the March & September equinoxes doesn't result in serious displacements over the long cycle of back-&-forth tropical-year-length drift.

Bromberg replies:

With regard to what Ossipoff is calling "year-round accuracy", note that I've been there, done that

 

That's great. Why you aren't still there, and are now doing something else, is your business, and none of my business.

Suit yourself.

immune to this drift because it explicitly uses the contemporaneously most accurate Delta T adjustment.


Even though I developed MOY and RAY, I don't particularly promote them, because I became convinced that it is better to use a simple fixed arithmetic leap rule to approximate the mean north solstitial year or the mean northward equinoctial year. Note also that when I detailed them in this CALNDR LISTSERV, they were met by severe criticism, which is why I practically abandoned them -- so I'm surprised that the same critics haven't been blasting you with similar remarks. Possibly it is because my description was very detailed, but yours has been consistently vague?

 

Do you realize that you're being vague now? If you want to say that something that I said was vague or unclear in meaning, then you need to specify what statement of mine you're referring to, and in what way it lacks meaning.

Otherwise it's just more of your usual vague, unsupported, nonspecific, referentless angry noises.

If you think that there's a valid criticism of, or objection to, using the mean tropical year, for the purpose of year-round accuracy (or maybe using the mean of the March equinox year & the September equinox year), then you need to say so. Otherwise we have no way of knowing what you're trying to say.


As an example of Ossipoff's vagueness, I have no idea what he means by "the mean of the March & September equinoxes",

 

No, I spoke of the mean of the March equinox year and the September equinox year.

Because that was said in the context of discussion of the choice of reference-tropical-year, for choosing the value of Y, then it should be obvious that I was referring to the mean of the lengths of the March equinox year and the September equinox year.



 

but anyway he persists in asserting that it "doesn't result in serious displacements over the long cycle of back-&-forth tropical-year-length drift" even though he hasn't evaluated or demonstrated the veracity of that claim in any way.

 

Don't worry about it.

If the use (for Y in my leapyear-rule) of the length of the mean tropical year, or the use of the mean of the lengths of the September equinox year & the March equinox year, would cause a problematic amount of periodic calendar-displacement over the long cycle of back-&-forth tropical-year-length drift, then your use of the June solstice year or the March equinox year would result in an even greater maximum displacement, measured throughout the year (instead of only at the June solstice or March equinox).

Yes, you don't propose using the March equinox year or the June solstice year over the entire (20,000 year?--I haven't looked at the graphs for a while) cycle of tropical-year length-changes that your graphs imply. But, even during the time that you would propose using one of those as the RTY, the result would be more maximum accumulated calendar-displacement (where that maximum is the maximum of calendar-displacements observed at all times of year), compared to what it would be with the mean tropical year as the RTY, or with the mean of the September equinox year's length and the March equinox year's length as the Y value..

 

As for the magnitude of the displacement over that long year-length-drift cycle, it was some time ago when I calculated it (based on your tropical-year-length graphs). So, right now I couldn't tell you what that magnitude was.

It wasn't much. A few days? I don't know. But, considering that it represents the extremes of a cycle with a period of 10,000 or 20,000 years or something, it didn't seem much at all.

The back & forth accumulated calendar-displacements, resulting from the ongoing tropical-year-length changes over each 10,000 years or so, are somewhat less each time (over the next several tens of thousands of years), according to your graphs. I mention that only so that you won't crow that I believed otherwise.

 

It wasn't very much. But, as I said, the amount doesn't matter, because the maximum, over all times of year, during that long cycle, is worse when you use the March equinox year or the June solstice year (instead of the mean tropical year,  or the mean of the lengths of the March & September equinox years) as the reference tropical year length for a calendar's leapyear-rule.

When I mentioned that the long-cycle calendar-displacement isn't so great, I didn't mean it as an assertion that I want to convince you of, or as an issue of angry contention. I just mentioned it, that's all. I'd gladly tell you what my estimate of the amount was, but it was some time ago when I calculated it,  and I didn't think that the number would be needed later.

(...and, as I've said, this matter of what the calendar will do over the next 10,000 years isn't of great interest to most people.)

You have a lot of anger, and a strong need to contradict. So much, that it sometimes motivates you to contradict, even when doing so requires you to say something that's obviously, blatantly, wrong. There have been several instances of that, and I've called attention to each when it happened.

Always, it's your anger, usually in the form of vague, nonspecific angry noises.  ...when not in the form of outright incorrect statements.

I have no idea why you have that anger and that need. I have no idea why you can't disagree  politely.  ...or why you can't behave peacefully, why you need to rage. That's none of my business.

Michael Ossipoff


 


-- Irv Bromberg, University of Toronto, Canada

http://www.sym454.org/seasons/