Subtraction of Displacement

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Subtraction of Displacement

Karl Palmen

Dear Michael, Irv, Victor, Walter and Calendar People

 

I’ll take some more time to read about what Michael has written about “oscillation” etc. before commenting on it. In the meantime I’ll demonstrate why subtracting displacement form the date of a solar ecliptic longitude is a good idea. For my demonstration, I choose the March equinox, but note that any other solar ecliptic longitude can be used.

 

For years 2017-2021 we have

Mon, 20 Mar 2017 10:28:31 GMT

Tue, 20 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 20 Mar 2020 03:49:35 GMT

Sat, 20 Mar 2021 09:37:05 GMT

From https://stellafane.org/misc/equinox.html

 

Now I use a minimum-displacement leap-week calendar with mean year (Y) 365.24215 days (as agreed by Michael) and displacement of -0.6288 days for year 2017. So for these years, we have displacements:

2017 -0.6288

2018 +0.61335

2019 +1.8555

2020 +3.09765 (leap year)

2021 -2.6602

 

I then convert the equinox dates to this calendar with 30-30-31-day quarters starting on Monday.

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.

 

Before subtracting the displacements, I convert them to days, hours, minutes  (rounded to nearest).

2017 –(0d 15h 05m)   

2018 +(0d 14h 43m)

2019 +(1d 20h 32m)

2020 +(3d 02h 21m)

2021 –(2d 15h 51m)

 

Finally I subtract the displacements from the dates of the March equinox in the leap week calendar.

Tue, 19 Mar 2017 01:34 GMT

Tue, 19 Mar 2018 01:22 GMT

Tue, 19 Mar 2019 01:26 GMT

Tue, 19 Mar 2020 01:29 GMT

Tue, 19 Mar 2021 01:28 GMT

Now  there are now just a few minutes of variation, which can be attributed to the gravitational effects of the other planets. Nearly all the ‘oscillation’ has been removed.

 

What one has effectively done here is isolate the jitter of the calendar from the equinox dates, so making it easy to analyse the drift of the equinox. This can be applied to any other solar ecliptic longitude. I have previously isolated jitter by choosing dates a whole number of calendar cycles apart. This is something that the concept of calendar displacement is useful for.

 

Karl

 

16(06(14

 

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Re: Subtraction of Displacement

Michael Ossipoff
Interesting. Subtracting the calculated displacements shows that something else is affecting the calendar-date-&-time of a SEL.

But, because you're looking at the March equinox, shouldn't Y be the length of the March equinox year? Using (a fairly near future value of) the MTY is sure to result in some drift in your final times.

But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements.

As you said, planetary-perturbations, &/or nutations, might cause the discrepencies, .

Michael Ossipoff



On Fri, Feb 10, 2017 at 8:09 AM, Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv, Victor, Walter and Calendar People

 

I’ll take some more time to read about what Michael has written about “oscillation” etc. before commenting on it. In the meantime I’ll demonstrate why subtracting displacement form the date of a solar ecliptic longitude is a good idea. For my demonstration, I choose the March equinox, but note that any other solar ecliptic longitude can be used.

 

For years 2017-2021 we have

Mon, 20 Mar 2017 10:28:31 GMT

Tue, 20 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 20 Mar 2020 03:49:35 GMT

Sat, 20 Mar 2021 09:37:05 GMT

From https://stellafane.org/misc/equinox.html

 

Now I use a minimum-displacement leap-week calendar with mean year (Y) 365.24215 days (as agreed by Michael) and displacement of -0.6288 days for year 2017. So for these years, we have displacements:

2017 -0.6288

2018 +0.61335

2019 +1.8555

2020 +3.09765 (leap year)

2021 -2.6602

 

I then convert the equinox dates to this calendar with 30-30-31-day quarters starting on Monday.

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.

 

Before subtracting the displacements, I convert them to days, hours, minutes  (rounded to nearest).

2017 –(0d 15h 05m)   

2018 +(0d 14h 43m)

2019 +(1d 20h 32m)

2020 +(3d 02h 21m)

2021 –(2d 15h 51m)

 

Finally I subtract the displacements from the dates of the March equinox in the leap week calendar.

Tue, 19 Mar 2017 01:34 GMT

Tue, 19 Mar 2018 01:22 GMT

Tue, 19 Mar 2019 01:26 GMT

Tue, 19 Mar 2020 01:29 GMT

Tue, 19 Mar 2021 01:28 GMT

Now  there are now just a few minutes of variation, which can be attributed to the gravitational effects of the other planets. Nearly all the ‘oscillation’ has been removed.

 

What one has effectively done here is isolate the jitter of the calendar from the equinox dates, so making it easy to analyse the drift of the equinox. This can be applied to any other solar ecliptic longitude. I have previously isolated jitter by choosing dates a whole number of calendar cycles apart. This is something that the concept of calendar displacement is useful for.

 

Karl

 

16(06(14

 


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Re: Subtraction of Displacement

Michael Ossipoff
I said:

"But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements."

If "oscillatory" implies regularity, then I probably should have just said "nonmonotonic", and not "oscillatory".

I said:


"As you said, planetary-perturbations, &/or nutations, might cause the discrepencies,"

When your source told when the equinoxes would be, I don't know if they were referring to the Sun's arrival at the actual or mean equinox. So I don't know if nutation is averaged out, for the purpose of those predicted equinox-times.

Another thing that would have some effect on the equinox times (unless it's averaged out too) is the Earth's motion about the Earth-Moon barycenter.

Though that barycenter is inside the Earth, that orbital motion of the Earth about it would be enough to change the time of an SEL by up to around a half-hour--just a very rough order-of-magnitude estimate.

I said:

"But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements."

If "oscillatory" implies regularity, then I probably should have just said "nonmonotonic", and not "oscillatory".

I said:


"As you said, planetary-perturbations, &/or nutations, might cause the discrepencies,"

When your source told when the equinoxes would be, I don't know if they were referring to the Sun's arrival at the actual or mean equinox. So I don't know if nutation is averaged out, for the purpose of those predicted equinox-times.

Another thing that would have some effect on the equinox times (unless it's averaged out too) is the Earth's motion about the Earth-Moon barycenter.

Though that barycenter is inside the Earth, that orbital motion of the Earth about it would be enough to change the time of an SEL by up to around a half-hour--just a very rough order-of-magnitude estimate.

I said:

"But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements."

If "oscillatory" implies regularity, then I probably should have just said "nonmonotonic", and not "oscillatory".

I said:


"As you said, planetary-perturbations, &/or nutations, might cause the discrepencies,"

When your source told when the equinoxes would be, I don't know if they were referring to the Sun's arrival at the actual or mean equinox. So I don't know if nutation is averaged out, for the purpose of those predicted equinox-times.

Another thing that would have some effect on the equinox times (unless it's averaged out too) is the Earth's motion about the Earth-Moon barycenter.

Though that barycenter is inside the Earth, that orbital motion of the Earth about it would be enough to change the time of an SEL by up to around a half-hour--just a very rough order-of-magnitude estimate.

I said:

"But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements."

If "oscillatory" implies regularity, then I probably should have just said "nonmonotonic", and not "oscillatory".

I said:


"As you said, planetary-perturbations, &/or nutations, might cause the discrepencies,"

When your source told when the equinoxes would be, I don't know if they were referring to the Sun's arrival at the actual or mean equinox. So I don't know if nutation is averaged out, for the purpose of those predicted equinox-times.

Another thing that would have some effect on the equinox times (unless it's averaged out too) is the Earth's motion about the Earth-Moon barycenter.

Though that barycenter is inside the Earth, that orbital motion of the Earth about it would be enough to change the time of an SEL by up to around a half-hour--just a very rough order-of-magnitude estimate.

You said:

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.

[endquote]

You think?

Well, I said that i was referring to the oscillation of an SEL's calendar-date, from one leapyear to the next.

You be the judge.

Michael Ossipoff

(All of this posting's replies are above this point. I have no way to delete large amounts of text.)


On Sat, Feb 11, 2017 at 12:40 AM, Michael Ossipoff <[hidden email]> wrote:
Interesting. Subtracting the calculated displacements shows that something else is affecting the calendar-date-&-time of a SEL.

But, because you're looking at the March equinox, shouldn't Y be the length of the March equinox year? Using (a fairly near future value of) the MTY is sure to result in some drift in your final times.

But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements.

As you said, planetary-perturbations, &/or nutations, might cause the discrepencies, .

Michael Ossipoff



On Fri, Feb 10, 2017 at 8:09 AM, Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv, Victor, Walter and Calendar People

 

I’ll take some more time to read about what Michael has written about “oscillation” etc. before commenting on it. In the meantime I’ll demonstrate why subtracting displacement form the date of a solar ecliptic longitude is a good idea. For my demonstration, I choose the March equinox, but note that any other solar ecliptic longitude can be used.

 

For years 2017-2021 we have

Mon, 20 Mar 2017 10:28:31 GMT

Tue, 20 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 20 Mar 2020 03:49:35 GMT

Sat, 20 Mar 2021 09:37:05 GMT

From https://stellafane.org/misc/equinox.html

 

Now I use a minimum-displacement leap-week calendar with mean year (Y) 365.24215 days (as agreed by Michael) and displacement of -0.6288 days for year 2017. So for these years, we have displacements:

2017 -0.6288

2018 +0.61335

2019 +1.8555

2020 +3.09765 (leap year)

2021 -2.6602

 

I then convert the equinox dates to this calendar with 30-30-31-day quarters starting on Monday.

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.



On Sat, Feb 11, 2017 at 12:40 AM, Michael Ossipoff <[hidden email]> wrote:
Interesting. Subtracting the calculated displacements shows that something else is affecting the calendar-date-&-time of a SEL.

But, because you're looking at the March equinox, shouldn't Y be the length of the March equinox year? Using (a fairly near future value of) the MTY is sure to result in some drift in your final times.

But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements.

As you said, planetary-perturbations, &/or nutations, might cause the discrepencies, .

Michael Ossipoff



On Fri, Feb 10, 2017 at 8:09 AM, Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv, Victor, Walter and Calendar People

 

I’ll take some more time to read about what Michael has written about “oscillation” etc. before commenting on it. In the meantime I’ll demonstrate why subtracting displacement form the date of a solar ecliptic longitude is a good idea. For my demonstration, I choose the March equinox, but note that any other solar ecliptic longitude can be used.

 

For years 2017-2021 we have

Mon, 20 Mar 2017 10:28:31 GMT

Tue, 20 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 20 Mar 2020 03:49:35 GMT

Sat, 20 Mar 2021 09:37:05 GMT

From https://stellafane.org/misc/equinox.html

 

Now I use a minimum-displacement leap-week calendar with mean year (Y) 365.24215 days (as agreed by Michael) and displacement of -0.6288 days for year 2017. So for these years, we have displacements:

2017 -0.6288

2018 +0.61335

2019 +1.8555

2020 +3.09765 (leap year)

2021 -2.6602

 

I then convert the equinox dates to this calendar with 30-30-31-day quarters starting on Monday.

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.



On Sat, Feb 11, 2017 at 12:40 AM, Michael Ossipoff <[hidden email]> wrote:
Interesting. Subtracting the calculated displacements shows that something else is affecting the calendar-date-&-time of a SEL.

But, because you're looking at the March equinox, shouldn't Y be the length of the March equinox year? Using (a fairly near future value of) the MTY is sure to result in some drift in your final times.

But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements.

As you said, planetary-perturbations, &/or nutations, might cause the discrepencies, .

Michael Ossipoff



On Fri, Feb 10, 2017 at 8:09 AM, Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv, Victor, Walter and Calendar People

 

I’ll take some more time to read about what Michael has written about “oscillation” etc. before commenting on it. In the meantime I’ll demonstrate why subtracting displacement form the date of a solar ecliptic longitude is a good idea. For my demonstration, I choose the March equinox, but note that any other solar ecliptic longitude can be used.

 

For years 2017-2021 we have

Mon, 20 Mar 2017 10:28:31 GMT

Tue, 20 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 20 Mar 2020 03:49:35 GMT

Sat, 20 Mar 2021 09:37:05 GMT

From https://stellafane.org/misc/equinox.html

 

Now I use a minimum-displacement leap-week calendar with mean year (Y) 365.24215 days (as agreed by Michael) and displacement of -0.6288 days for year 2017. So for these years, we have displacements:

2017 -0.6288

2018 +0.61335

2019 +1.8555

2020 +3.09765 (leap year)

2021 -2.6602

 

I then convert the equinox dates to this calendar with 30-30-31-day quarters starting on Monday.

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.



On Sat, Feb 11, 2017 at 12:40 AM, Michael Ossipoff <[hidden email]> wrote:
Interesting. Subtracting the calculated displacements shows that something else is affecting the calendar-date-&-time of a SEL.

But, because you're looking at the March equinox, shouldn't Y be the length of the March equinox year? Using (a fairly near future value of) the MTY is sure to result in some drift in your final times.

But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements.

As you said, planetary-perturbations, &/or nutations, might cause the discrepencies, .

Michael Ossipoff



On Fri, Feb 10, 2017 at 8:09 AM, Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv, Victor, Walter and Calendar People

 

I’ll take some more time to read about what Michael has written about “oscillation” etc. before commenting on it. In the meantime I’ll demonstrate why subtracting displacement form the date of a solar ecliptic longitude is a good idea. For my demonstration, I choose the March equinox, but note that any other solar ecliptic longitude can be used.

 

For years 2017-2021 we have

Mon, 20 Mar 2017 10:28:31 GMT

Tue, 20 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 20 Mar 2020 03:49:35 GMT

Sat, 20 Mar 2021 09:37:05 GMT

From https://stellafane.org/misc/equinox.html

 

Now I use a minimum-displacement leap-week calendar with mean year (Y) 365.24215 days (as agreed by Michael) and displacement of -0.6288 days for year 2017. So for these years, we have displacements:

2017 -0.6288

2018 +0.61335

2019 +1.8555

2020 +3.09765 (leap year)

2021 -2.6602

 

I then convert the equinox dates to this calendar with 30-30-31-day quarters starting on Monday.

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.

 

Before subtracting the displacements, I convert them to days, hours, minutes  (rounded to nearest).

2017 –(0d 15h 05m)   

2018 +(0d 14h 43m)

2019 +(1d 20h 32m)

2020 +(3d 02h 21m)

2021 –(2d 15h 51m)

 

Finally I subtract the displacements from the dates of the March equinox in the leap week calendar.

Tue, 19 Mar 2017 01:34 GMT

Tue, 19 Mar 2018 01:22 GMT

Tue, 19 Mar 2019 01:26 GMT

Tue, 19 Mar 2020 01:29 GMT

Tue, 19 Mar 2021 01:28 GMT

Now  there are now just a few minutes of variation, which can be attributed to the gravitational effects of the other planets. Nearly all the ‘oscillation’ has been removed.

 

What one has effectively done here is isolate the jitter of the calendar from the equinox dates, so making it easy to analyse the drift of the equinox. This can be applied to any other solar ecliptic longitude. I have previously isolated jitter by choosing dates a whole number of calendar cycles apart. This is something that the concept of calendar displacement is useful for.

 

Karl

 

16(06(14

 



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Re: Subtraction of Displacement

Michael Ossipoff

Somehow, I posted a 3-times repetition of the first part of the post. That could have prevented the end of the post from being noticed, and so I'm re-posting it here:


You said:

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.

[endquote]

You think?

Well, I said that i was referring to the oscillation of an SEL's calendar-date, from one leapyear to the next.

You be the judge.

Michael Ossipoff

(All of this posting's replies are above this point. I have no way to delete large amounts of text.)

On Sat, Feb 11, 2017 at 9:57 AM, Michael Ossipoff <[hidden email]> wrote:
I said:

"But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements."

If "oscillatory" implies regularity, then I probably should have just said "nonmonotonic", and not "oscillatory".

I said:


"As you said, planetary-perturbations, &/or nutations, might cause the discrepencies,"

When your source told when the equinoxes would be, I don't know if they were referring to the Sun's arrival at the actual or mean equinox. So I don't know if nutation is averaged out, for the purpose of those predicted equinox-times.

Another thing that would have some effect on the equinox times (unless it's averaged out too) is the Earth's motion about the Earth-Moon barycenter.

Though that barycenter is inside the Earth, that orbital motion of the Earth about it would be enough to change the time of an SEL by up to around a half-hour--just a very rough order-of-magnitude estimate.

I said:

"But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements."

If "oscillatory" implies regularity, then I probably should have just said "nonmonotonic", and not "oscillatory".

I said:


"As you said, planetary-perturbations, &/or nutations, might cause the discrepencies,"

When your source told when the equinoxes would be, I don't know if they were referring to the Sun's arrival at the actual or mean equinox. So I don't know if nutation is averaged out, for the purpose of those predicted equinox-times.

Another thing that would have some effect on the equinox times (unless it's averaged out too) is the Earth's motion about the Earth-Moon barycenter.

Though that barycenter is inside the Earth, that orbital motion of the Earth about it would be enough to change the time of an SEL by up to around a half-hour--just a very rough order-of-magnitude estimate.

I said:

"But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements."

If "oscillatory" implies regularity, then I probably should have just said "nonmonotonic", and not "oscillatory".

I said:


"As you said, planetary-perturbations, &/or nutations, might cause the discrepencies,"

When your source told when the equinoxes would be, I don't know if they were referring to the Sun's arrival at the actual or mean equinox. So I don't know if nutation is averaged out, for the purpose of those predicted equinox-times.

Another thing that would have some effect on the equinox times (unless it's averaged out too) is the Earth's motion about the Earth-Moon barycenter.

Though that barycenter is inside the Earth, that orbital motion of the Earth about it would be enough to change the time of an SEL by up to around a half-hour--just a very rough order-of-magnitude estimate.

I said:

"But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements."

If "oscillatory" implies regularity, then I probably should have just said "nonmonotonic", and not "oscillatory".

I said:


"As you said, planetary-perturbations, &/or nutations, might cause the discrepencies,"

When your source told when the equinoxes would be, I don't know if they were referring to the Sun's arrival at the actual or mean equinox. So I don't know if nutation is averaged out, for the purpose of those predicted equinox-times.

Another thing that would have some effect on the equinox times (unless it's averaged out too) is the Earth's motion about the Earth-Moon barycenter.

Though that barycenter is inside the Earth, that orbital motion of the Earth about it would be enough to change the time of an SEL by up to around a half-hour--just a very rough order-of-magnitude estimate.

You said:

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.

[endquote]

You think?

Well, I said that i was referring to the oscillation of an SEL's calendar-date, from one leapyear to the next.

You be the judge.

Michael Ossipoff

(All of this posting's replies are above this point. I have no way to delete large amounts of text.)


On Sat, Feb 11, 2017 at 12:40 AM, Michael Ossipoff <[hidden email]> wrote:
Interesting. Subtracting the calculated displacements shows that something else is affecting the calendar-date-&-time of a SEL.

But, because you're looking at the March equinox, shouldn't Y be the length of the March equinox year? Using (a fairly near future value of) the MTY is sure to result in some drift in your final times.

But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements.

As you said, planetary-perturbations, &/or nutations, might cause the discrepencies, .

Michael Ossipoff



On Fri, Feb 10, 2017 at 8:09 AM, Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv, Victor, Walter and Calendar People

 

I’ll take some more time to read about what Michael has written about “oscillation” etc. before commenting on it. In the meantime I’ll demonstrate why subtracting displacement form the date of a solar ecliptic longitude is a good idea. For my demonstration, I choose the March equinox, but note that any other solar ecliptic longitude can be used.

 

For years 2017-2021 we have

Mon, 20 Mar 2017 10:28:31 GMT

Tue, 20 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 20 Mar 2020 03:49:35 GMT

Sat, 20 Mar 2021 09:37:05 GMT

From https://stellafane.org/misc/equinox.html

 

Now I use a minimum-displacement leap-week calendar with mean year (Y) 365.24215 days (as agreed by Michael) and displacement of -0.6288 days for year 2017. So for these years, we have displacements:

2017 -0.6288

2018 +0.61335

2019 +1.8555

2020 +3.09765 (leap year)

2021 -2.6602

 

I then convert the equinox dates to this calendar with 30-30-31-day quarters starting on Monday.

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.



On Sat, Feb 11, 2017 at 12:40 AM, Michael Ossipoff <[hidden email]> wrote:
Interesting. Subtracting the calculated displacements shows that something else is affecting the calendar-date-&-time of a SEL.

But, because you're looking at the March equinox, shouldn't Y be the length of the March equinox year? Using (a fairly near future value of) the MTY is sure to result in some drift in your final times.

But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements.

As you said, planetary-perturbations, &/or nutations, might cause the discrepencies, .

Michael Ossipoff



On Fri, Feb 10, 2017 at 8:09 AM, Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv, Victor, Walter and Calendar People

 

I’ll take some more time to read about what Michael has written about “oscillation” etc. before commenting on it. In the meantime I’ll demonstrate why subtracting displacement form the date of a solar ecliptic longitude is a good idea. For my demonstration, I choose the March equinox, but note that any other solar ecliptic longitude can be used.

 

For years 2017-2021 we have

Mon, 20 Mar 2017 10:28:31 GMT

Tue, 20 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 20 Mar 2020 03:49:35 GMT

Sat, 20 Mar 2021 09:37:05 GMT

From https://stellafane.org/misc/equinox.html

 

Now I use a minimum-displacement leap-week calendar with mean year (Y) 365.24215 days (as agreed by Michael) and displacement of -0.6288 days for year 2017. So for these years, we have displacements:

2017 -0.6288

2018 +0.61335

2019 +1.8555

2020 +3.09765 (leap year)

2021 -2.6602

 

I then convert the equinox dates to this calendar with 30-30-31-day quarters starting on Monday.

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.



On Sat, Feb 11, 2017 at 12:40 AM, Michael Ossipoff <[hidden email]> wrote:
Interesting. Subtracting the calculated displacements shows that something else is affecting the calendar-date-&-time of a SEL.

But, because you're looking at the March equinox, shouldn't Y be the length of the March equinox year? Using (a fairly near future value of) the MTY is sure to result in some drift in your final times.

But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements.

As you said, planetary-perturbations, &/or nutations, might cause the discrepencies, .

Michael Ossipoff



On Fri, Feb 10, 2017 at 8:09 AM, Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv, Victor, Walter and Calendar People

 

I’ll take some more time to read about what Michael has written about “oscillation” etc. before commenting on it. In the meantime I’ll demonstrate why subtracting displacement form the date of a solar ecliptic longitude is a good idea. For my demonstration, I choose the March equinox, but note that any other solar ecliptic longitude can be used.

 

For years 2017-2021 we have

Mon, 20 Mar 2017 10:28:31 GMT

Tue, 20 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 20 Mar 2020 03:49:35 GMT

Sat, 20 Mar 2021 09:37:05 GMT

From https://stellafane.org/misc/equinox.html

 

Now I use a minimum-displacement leap-week calendar with mean year (Y) 365.24215 days (as agreed by Michael) and displacement of -0.6288 days for year 2017. So for these years, we have displacements:

2017 -0.6288

2018 +0.61335

2019 +1.8555

2020 +3.09765 (leap year)

2021 -2.6602

 

I then convert the equinox dates to this calendar with 30-30-31-day quarters starting on Monday.

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.



On Sat, Feb 11, 2017 at 12:40 AM, Michael Ossipoff <[hidden email]> wrote:
Interesting. Subtracting the calculated displacements shows that something else is affecting the calendar-date-&-time of a SEL.

But, because you're looking at the March equinox, shouldn't Y be the length of the March equinox year? Using (a fairly near future value of) the MTY is sure to result in some drift in your final times.

But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements.

As you said, planetary-perturbations, &/or nutations, might cause the discrepencies, .

Michael Ossipoff



On Fri, Feb 10, 2017 at 8:09 AM, Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv, Victor, Walter and Calendar People

 

I’ll take some more time to read about what Michael has written about “oscillation” etc. before commenting on it. In the meantime I’ll demonstrate why subtracting displacement form the date of a solar ecliptic longitude is a good idea. For my demonstration, I choose the March equinox, but note that any other solar ecliptic longitude can be used.

 

For years 2017-2021 we have

Mon, 20 Mar 2017 10:28:31 GMT

Tue, 20 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 20 Mar 2020 03:49:35 GMT

Sat, 20 Mar 2021 09:37:05 GMT

From https://stellafane.org/misc/equinox.html

 

Now I use a minimum-displacement leap-week calendar with mean year (Y) 365.24215 days (as agreed by Michael) and displacement of -0.6288 days for year 2017. So for these years, we have displacements:

2017 -0.6288

2018 +0.61335

2019 +1.8555

2020 +3.09765 (leap year)

2021 -2.6602

 

I then convert the equinox dates to this calendar with 30-30-31-day quarters starting on Monday.

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.

 

Before subtracting the displacements, I convert them to days, hours, minutes  (rounded to nearest).

2017 –(0d 15h 05m)   

2018 +(0d 14h 43m)

2019 +(1d 20h 32m)

2020 +(3d 02h 21m)

2021 –(2d 15h 51m)

 

Finally I subtract the displacements from the dates of the March equinox in the leap week calendar.

Tue, 19 Mar 2017 01:34 GMT

Tue, 19 Mar 2018 01:22 GMT

Tue, 19 Mar 2019 01:26 GMT

Tue, 19 Mar 2020 01:29 GMT

Tue, 19 Mar 2021 01:28 GMT

Now  there are now just a few minutes of variation, which can be attributed to the gravitational effects of the other planets. Nearly all the ‘oscillation’ has been removed.

 

What one has effectively done here is isolate the jitter of the calendar from the equinox dates, so making it easy to analyse the drift of the equinox. This can be applied to any other solar ecliptic longitude. I have previously isolated jitter by choosing dates a whole number of calendar cycles apart. This is something that the concept of calendar displacement is useful for.

 

Karl

 

16(06(14

 




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Re: Subtraction of Displacement

Karl Palmen
In reply to this post by Michael Ossipoff

Dear Michael and Calendar People

 

From: East Carolina University Calendar discussion List [mailto:[hidden email]] On Behalf Of Michael Ossipoff
Sent: 11 February 2017 05:41
To: [hidden email]
Subject: Re: Subtraction of Displacement

 

Interesting. Subtracting the calculated displacements shows that something else is affecting the calendar-date-&-time of a SEL.

But, because you're looking at the March equinox, shouldn't Y be the length of the March equinox year? Using (a fairly near future value of) the MTY is sure to result in some drift in your final times.

KARL REPLIES: One can use any Y and any SEL and over a long time, it will show the drift.

If one uses Y=365.25, one can see the Julian mean year drift over just 5 years:

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

 

One gets (with D(2018)=0):

Tue, 19 Mar 2017 16:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Tue, 19 Mar 2019 15:58:05 GMT

Tue, 19 Mar 2020 15:49:35 GMT

Tue, 19 Mar 2021 15:37:05 GMT

 

MICHAEL CONTINUED: But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements.

As you said, planetary-perturbations, &/or nutations, might cause the discrepencies, .

KARL REPLIES: Yes, I believe that is the cause of the variation of a few minutes.

Karl

16(06(17

 

Michael Ossipoff

 

 

On Fri, Feb 10, 2017 at 8:09 AM, Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv, Victor, Walter and Calendar People

 

I’ll take some more time to read about what Michael has written about “oscillation” etc. before commenting on it. In the meantime I’ll demonstrate why subtracting displacement form the date of a solar ecliptic longitude is a good idea. For my demonstration, I choose the March equinox, but note that any other solar ecliptic longitude can be used.

 

For years 2017-2021 we have

Mon, 20 Mar 2017 10:28:31 GMT

Tue, 20 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 20 Mar 2020 03:49:35 GMT

Sat, 20 Mar 2021 09:37:05 GMT

From https://stellafane.org/misc/equinox.html

 

Now I use a minimum-displacement leap-week calendar with mean year (Y) 365.24215 days (as agreed by Michael) and displacement of -0.6288 days for year 2017. So for these years, we have displacements:

2017 -0.6288

2018 +0.61335

2019 +1.8555

2020 +3.09765 (leap year)

2021 -2.6602

 

I then convert the equinox dates to this calendar with 30-30-31-day quarters starting on Monday.

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.

 

Before subtracting the displacements, I convert them to days, hours, minutes  (rounded to nearest).

2017 –(0d 15h 05m)   

2018 +(0d 14h 43m)

2019 +(1d 20h 32m)

2020 +(3d 02h 21m)

2021 –(2d 15h 51m)

 

Finally I subtract the displacements from the dates of the March equinox in the leap week calendar.

Tue, 19 Mar 2017 01:34 GMT

Tue, 19 Mar 2018 01:22 GMT

Tue, 19 Mar 2019 01:26 GMT

Tue, 19 Mar 2020 01:29 GMT

Tue, 19 Mar 2021 01:28 GMT

Now  there are now just a few minutes of variation, which can be attributed to the gravitational effects of the other planets. Nearly all the ‘oscillation’ has been removed.

 

What one has effectively done here is isolate the jitter of the calendar from the equinox dates, so making it easy to analyse the drift of the equinox. This can be applied to any other solar ecliptic longitude. I have previously isolated jitter by choosing dates a whole number of calendar cycles apart. This is something that the concept of calendar displacement is useful for.

 

Karl

 

16(06(14

 

 

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Re: Subtraction of Displacement

Michael Ossipoff


On Mon, Feb 13, 2017 at 8:05 AM, Karl Palmen <[hidden email]> wrote:

Dear Michael and Calendar People

 

From: East Carolina University Calendar discussion List [mailto:[hidden email]] On Behalf Of Michael Ossipoff
Sent: 11 February 2017 05:41
To: [hidden email]
Subject: Re: Subtraction of Displacement

 

Interesting. Subtracting the calculated displacements shows that something else is affecting the calendar-date-&-time of a SEL.

But, because you're looking at the March equinox, shouldn't Y be the length of the March equinox year? Using (a fairly near future value of) the MTY is sure to result in some drift in your final times.

KARL REPLIES: One can use any Y and any SEL and over a long time, it will show the drift.


I just meant that the drift of the date/time of a SEL will be less if Y matches the length of that SEL's tropical-year.

If one uses Y=365.25, one can see the Julian mean year drift over just 5 years:

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

 

One gets (with D(2018)=0):

Tue, 19 Mar 2017 16:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Tue, 19 Mar 2019 15:58:05 GMT

Tue, 19 Mar 2020 15:49:35 GMT

Tue, 19 Mar 2021 15:37:05 GMT

 

MICHAEL CONTINUED: But that unidirectional drift can't explain the nonmonotonic, oscillatory, changes in the times that remain after the subtraction of the displacements.

As you said, planetary-perturbations, &/or nutations, might cause the discrepencies, .

KARL REPLIES: Yes, I believe that is the cause of the variation of a few minutes.


...and our orbital motion about the Earth-Moon barycenter, unless that's averaged out, for that table's equinox times.  It's potentially as much as roughly a half-hour, in the time of a SEL.

Michael Ossipoff

Karl

16(06(17

 

Michael Ossipoff

 

 

On Fri, Feb 10, 2017 at 8:09 AM, Karl Palmen <[hidden email]> wrote:

Dear Michael, Irv, Victor, Walter and Calendar People

 

I’ll take some more time to read about what Michael has written about “oscillation” etc. before commenting on it. In the meantime I’ll demonstrate why subtracting displacement form the date of a solar ecliptic longitude is a good idea. For my demonstration, I choose the March equinox, but note that any other solar ecliptic longitude can be used.

 

For years 2017-2021 we have

Mon, 20 Mar 2017 10:28:31 GMT

Tue, 20 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 20 Mar 2020 03:49:35 GMT

Sat, 20 Mar 2021 09:37:05 GMT

From https://stellafane.org/misc/equinox.html

 

Now I use a minimum-displacement leap-week calendar with mean year (Y) 365.24215 days (as agreed by Michael) and displacement of -0.6288 days for year 2017. So for these years, we have displacements:

2017 -0.6288

2018 +0.61335

2019 +1.8555

2020 +3.09765 (leap year)

2021 -2.6602

 

I then convert the equinox dates to this calendar with 30-30-31-day quarters starting on Monday.

Mon, 18 Mar 2017 10:28:31 GMT

Tue, 19 Mar 2018 16:14:45 GMT

Wed, 20 Mar 2019 21:58:05 GMT

Fri, 22 Mar 2020 03:49:35 GMT

Sat, 16 Mar 2021 09:37:05 GMT

They are spread over a week (Sat 16 to Fri 22). I think this may be what Michael means by ‘oscillation’.

 

Before subtracting the displacements, I convert them to days, hours, minutes  (rounded to nearest).

2017 –(0d 15h 05m)   

2018 +(0d 14h 43m)

2019 +(1d 20h 32m)

2020 +(3d 02h 21m)

2021 –(2d 15h 51m)

 

Finally I subtract the displacements from the dates of the March equinox in the leap week calendar.

Tue, 19 Mar 2017 01:34 GMT

Tue, 19 Mar 2018 01:22 GMT

Tue, 19 Mar 2019 01:26 GMT

Tue, 19 Mar 2020 01:29 GMT

Tue, 19 Mar 2021 01:28 GMT

Now  there are now just a few minutes of variation, which can be attributed to the gravitational effects of the other planets. Nearly all the ‘oscillation’ has been removed.

 

What one has effectively done here is isolate the jitter of the calendar from the equinox dates, so making it easy to analyse the drift of the equinox. This can be applied to any other solar ecliptic longitude. I have previously isolated jitter by choosing dates a whole number of calendar cycles apart. This is something that the concept of calendar displacement is useful for.

 

Karl

 

16(06(14