quote="carriere.francois" wrote][/b]
AJ wrote:Therese Hamilton wrote:AJ wrote:
Would this one minute increase or decrease the Lahiri ayanamsa? That is, would the one minute increase or decrease the longitudes of planets in charts?
Increases.
Well, it depends on the period of the year. There are probably astronomical values I am not aware of that explain this. From my experience, it is always with 1'30" from Lahiri, plus or minus.
Hmmm... This is not correct. The value of ayanamsa does not oscillate plus or minus for different periods of the year, Chitrapaksa compared to Lahiri or not. You might check if your software is computing the ayanamsa correctly.
Most ayanamshas are defined by a milestone or epoch with a first offset value for that ayanamsha. This does not oscillate with the time of year or seasons. Chitrapaksa since it is referenced to a fixed star you must know its precise position so it does not quite work like a regular ayanamsa offset. If you want Chitra, or the star Spica as it is known in the west, at 180 degrees you must calculate the tropical position of the star for the date and then subtract it from the tropical position of the planet or another sensitive point. This too is not affected by any oscillation due to the "period of the year".
Below are two sets of calculations for the ascendant at Washinton DC for the first day of the month for the next three years at 0600 hours. Note that the difference between Lahiri and Chitrpaksha has Chitrapaksha usually
about one arc minute ahead of Lahiri in the final calc. There is no plus or minus oscillation and the difference is not over an arc minute. When they are the same it is due to rounding, because the difference between them is not quite an arc minute. The actual difference is around 50 or 51 arc seconds if I remember right. The values are the degrees and minutes rather than to the second as it was just not worth the time to calculate to that degree of precision. Also, considering we are lucky to have a birth time accurate to a minute in time, calculating to the minute of arc is fine. At the end of the day, you really can't be more accurate than your original input data. One minute in time is equal to a quarter of a degree or 15 arc minutes.
I wanted to align them side by side but cannot do a table in the editor. Note that over three years
the values of Chiitrapaksa do not...
"...depends on the period of the year. ...is always with 1'30" from Lahiri, plus or minus".
Washington Ascendant Lahiri
1/ 1/2019 Mo 6:00 25°30'Sc
2/ 1/2019 Th 6:00 24°30'Sg
3/ 1/2019 Th 6:00 29° 2'Cp
4/ 1/2019 Su 6:00 23°17'Aq
5/ 1/2019 Tu 6:00 11° 9'Ar
6/ 1/2019 Sa 6:00 19°16'Ta
7/ 1/2019 Mo 6:00 17° 1'Ge
8/ 1/2019 We 6:00 12° 3'Ca
9/ 1/2019 Sa 6:00 6°20'Le
10/ 1/2019 Mo 6:00 0° 4'Vg
11/ 1/2019 Th 6:00 24°42'Vg
12/ 1/2019 Sa 6:00 0°13'Sc
1/ 1/2020 Tu 6:00 25°17'Sc
2/ 1/2020 Fr 6:00 24°13'Sg
3/ 1/2020 Sa 6:00 0° 7'Aq
4/ 1/2020 Tu 6:00 24°30'Aq
5/ 1/2020 Th 6:00 12°14'Ar
6/ 1/2020 Mo 6:00 20° 2'Ta
7/ 1/2020 We 6:00 17°39'Ge
8/ 1/2020 Fr 6:00 12°38'Ca
9/ 1/2020 Mo 6:00 6°55'Le
10/ 1/2020 We 6:00 0°39'Vg
11/ 1/2020 Sa 6:00 7°18'Li
12/ 1/2020 Mo 6:00 0°48'Sc
1/ 1/2021 Th 6:00 25°55'Sc
2/ 1/2021 Su 6:00 25° 1'Sg
3/ 1/2021 Su 6:00 29°45'Cp
4/ 1/2021 We 6:00 24° 5'Aq
5/ 1/2021 Fr 6:00 11°52'Ar
6/ 1/2021 Tu 6:00 19°46'Ta
7/ 1/2021 Th 6:00 17°26'Ge
8/ 1/2021 Sa 6:00 12°26'Ca
9/ 1/2021 Tu 6:00 6°42'Le
10/ 1/2021 Th 6:00 0°27'Vg
11/ 1/2021 Su 6:00 25° 4'Vg
12/ 1/2021 Tu 6:00 0°36'Sc
Washington Ascendant Chitrapaksa
1/ 1/2019 Mo 6:00 25°31'Sc
2/ 1/2019 Th 6:00 24°30'Sg
3/ 1/2019 Th 6:00 29° 3'Cp
4/ 1/2019 Su 6:00 23°17'Aq
5/ 1/2019 Tu 6:00 11°10'Ar
6/ 1/2019 Sa 6:00 19°16'Ta
7/ 1/2019 Mo 6:00 17° 2'Ge
8/ 1/2019 We 6:00 12° 4'Ca
9/ 1/2019 Sa 6:00 6°21'Le
10/ 1/2019 Mo 6:00 0° 5'Vg
11/ 1/2019 Th 6:00 24°43'Vg
12/ 1/2019 Sa 6:00 0°14'Sc
1/ 1/2020 Tu 6:00 25°18'Sc
2/ 1/2020 Fr 6:00 24°14'Sg
3/ 1/2020 Sa 6:00 0° 8'Aq
4/ 1/2020 Tu 6:00 24°30'Aq
5/ 1/2020 Th 6:00 12°15'Ar
6/ 1/2020 Mo 6:00 20° 3'Ta
7/ 1/2020 We 6:00 17°40'Ge
8/ 1/2020 Fr 6:00 12°39'Ca
9/ 1/2020 Mo 6:00 6°56'Le
10/ 1/2020 We 6:00 0°40'Vg
11/ 1/2020 Sa 6:00 7°20'Li
12/ 1/2020 Mo 6:00 0°49'Sc
1/ 1/2021 Th 6:00 25°56'Sc
2/ 1/2021 Su 6:00 25° 2'Sg
3/ 1/2021 Su 6:00 29°46'Cp
4/ 1/2021 We 6:00 24° 6'Aq
5/ 1/2021 Fr 6:00 11°53'Ar
6/ 1/2021 Tu 6:00 19°47'Ta
7/ 1/2021 Th 6:00 17°27'Ge
8/ 1/2021 Sa 6:00 12°27'Ca
9/ 1/2021 Tu 6:00 6°43'Le
10/ 1/2021 Th 6:00 0°28'Vg
11/ 1/2021 Su 6:00 25° 6'Vg
12/ 1/2021 Tu 6:00 0°37'Sc