converting geographic to geocentric lattitudes -- A REVIEW

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Dear Friends,

 

For your information and comment, my review is as below.

 

Thanks and regards,

 

tw

 

1. Please note "S. Balasundram & A.R. Raichur" are the authors of Universal Tables of Houses Book.

 

"Use the below formula (as given in Shri.K.Hariharan' s Universal Tables of Houses Book)."

 

 

2. In my opinion, Geocentric Latitude correction is nothing to do with the KP principle or KP SWs because of the following reasons:-- -

 

a). The maximum difference between Geocentric and Geographic latitudes is only about 11 minutes, not so much like in the case of Ayanamsa that it may not change the sub-lords and results of KP analysis, except in the border line case. I use and prefer the Geographic latitude as it is commonly used and well tested in East and West but I keep my mind open to experiment with the application of Geocentric latitude correction.

 

b) Preference for Geocentric positions in the Western literature is found mainly for "planetary" positions, for instance Llewellyn George is for Geocentric for the planetary positions, NOT for the Geocentric latitude as mentioned in the Astrosecrets & KP, Part II page 304;

 

c) The way of measuring the Geographic latitude seems in line what is required for the calculation of house cusps and the Geocentric latitude may not fulfill this condition. One may wonder if the Geocentric positions of all planets are used, why to use the Geographic latitude of birth place? The difference is that all planets are moving in the sky to measure from the center of earth but the birth place is located on earth at different levels from sea. Also N Blunsdon points out with pictures in "Low Thoughts on High Latitudes" that the angle, which determines the Ascendant, is much more accurately given by Geographic latitude than by Geocentric latitude. (Geoffrey Dean: Recent Advances in Natal Astrology page 183);

 

d) In tracking planets which are orbiting the Earth in space, the preference to use the geocentric coordinates is understandable. But for tracking a location of birth on the surface of Earth, the Geographic latitude measured on earth is supposed to represent the place of birth more accurately compared to a Geocentric representation measured from the center of earth because we live on earth, not in space.

 

e) Pl note the NASA or Swiss ephemeris' s Geocentric positions are "only for planetary positions" and not to be confused with the Geographic Latitudes of birth place. In the Western charts, Geocentric means Geocentric positions of planets and the Latitudes of birth place is Geographic. The Geocentric Latitude option is not yet available in the Astrodienst, the mostly relied accurate Western SW also providing the Hindu charts using Lahiri ayanamsa. It shows not yet much demand for Geocentric Latitude.

 

"Cuspal positions in any KP chart has to be erected only by taking this geocentric latitude for the Place of Birth, because NASA's data on planetary positions are provided only taking into consideration this Geocentric Latitudes, with respect to Earth's Centre point."

 

3. The Geocentric latitude equivalent to Geographic one can be found by the formula (UTOH or Astrosecrets & KP, Part II):

 

tan A = tan B x 0.993 30546

where A & B are the Geographic and Geocentric latitudes.

 

(or Log tan A = Log tan B + 9.9970828)

 

4. Since the decimal difference is not a big deal at all, for the easy reference, the following table values have been given (UTOH or Astrosecrets & KP, Part II) and to make a short list the more or less values are combined, for instance, for 10 or 80 deg of Geographic Latitudes, the correction minute 3.9 min is to be deducted from Geographic Latitudes to get Geocentric Latitudes; for 33 or 57 deg of Geographic Latitudes, the correction minute 10.6 min is to be substracted.

 

Table 14: Geocentric Correction to Latitudes

(Subtract from Geographic Latitudes)

 

GL.CM....GL

0--- 0.0-- 90

1 ---0.4-- 89

2----0.8-- 88

3-- -1.2-- 87

4-- -1.6-- 86

5-- -2.0-- 85

6 ---2.4-- 84

7 ---2.8-- 83

8 ---3.2-- 82

9-- -3.6-- 81

10- -3.9--80

11-- 4.3-- 79

12 --4.7-- 78

13 --5.0-- 77

14 --5.4-- 76

15 --5.8-- 75

16 --6.1-- 74

17 --6.4-- 73

18 --6.8-- 72

19 --7.1-- 71

20 --7.4-- 70

21 --7.7-- 69

22 --8.0-- 68

23 --8.3-- 67

24-- 8.6-- 66

25 --8.8-- 65

26 --9.1-- 64

27 --9.3-- 63

28 --9.6-- 62

29 --9.8-- 61

30 --0.0-- 60

31 -10.2-- 59

32 -10.4-- 58

33 -10.6-- 57

34 -10.7-- 56

35 -10.8-- 55

36- 11.0-- 54

37 -11.1-- 53

38 -11.2-- 52

39 -11.3-- 51

40 -11.4-- 50

41 -11.4-- 49

42 -11.5 --48

43 -11.5-- 47

44 -11.6-- 46

45 -11.6-- 45

 

GL= Geographic Latitude in Degree

 

CM= Correction in Minute

 

14. In the Example Chart 2, Geographic latitude 23N is converted

into Geocentric latitude 22N52 by subtracting 8min for 23deg as

given in Table 25. To get the cuspal position for 22N52 by

interpolation from the values for 22° N and 23° N, the cuspal

positions for 22° N are calculated as follows.

 

 

, Mohan Kumar Ragunathan <kpmk_astrology wrote:>> Dear Rao Sir,> Thanks again for the comment.> My intention is to help those who want to know about conversion from geographical to geocentric latitude.> Any SW not considering the Geocentric conversion in this manner for cuspal positions cannot be a KP SW at all.> One can check the geocentric values given by any SW by using the calculation I have mentioned here. > Cuspal positions in any KP chart has to be erected only by taking this geocentric latitude for the Place of Birth, because NASA's data on planetary positions are provided only taking into consideration this Geocentric Latitudes, with respect to Earth's Centre point. (KP Ephemeris - from the year 1980 onwards - notifies this aspect.) > Hence, the Cuspal positions also should be so. Just one of the basic lessons in KP.> Shri KSK had used only geographical latitudes - some may mention. > Sorry to say, it's sheer ignorance. May be our Guruji was not aware at that time. > Let's be clear in WHAT IS WHAT.> > With thanks and warm regards,> > Mohan Kumar.R.> Scientific Astrologer & Spoken English Tutor> Advanced Stellar Astrology Research Academy (KP based)> 219/84, Moongapadi St.,Gugai, SALEM - 636 006> Cell: 99443-07025> > --- On Wed, 8/27/08, Yogesh Rao Lajmi lyrastro1 wrote:> > Yogesh Rao Lajmi lyrastro1 Re: Re: converting geographic to geocentric lattitudes> > Wednesday, August 27, 2008, 6:38 AM> > > > > > > > > Dear Mohan Kumar,> Most of the better SWs today give the option for geocentric positions/chart. ..> For example Mr.Raichur's SW which I use has incorporated it....> With best wishes,> L.Y.Rao.> > > > > Mohan Kumar Ragunathan <kpmk_astrology@ >> @gro ups.com> Wednesday, 27 August, 2008 9:36:11 AM> Re: Re: converting geographic to geocentric lattitudes> > > > > > > > > Dear Swamy Ji,> Thanks for Shri TinWin's guidance.> To get accurate value, just use a scientific calculator. > Every KP astrologer should have one. It costs just Rs. 300 - 700. Go for a higher version around Rs. 600 - 700. > Learn how to use The Deg-Min-Sec (DMS) button. > Use the below formula (as given in Shri.K.Hariharan' s Universal Tables of Houses Book).> > To convert the Geographical Latitude of a Place to its Geocentric Latitude, do as below:> ------------ --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- --------> Example: for SALEM (TN): Geographic Lat is 11.39 N = Geocentric Lat is 11.34.27 N> ------------ --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- --------> Step 1: Press TAN button; > Press 11, then DMS button;> Press 39, then DMS button > (You will get this answer) = 0.206180118> Now multiply this answer by x 0.99330546 > (You will get another answer) = 0.204799837.> Keep it on the screen.> Step 2: Press Shift Button, then press TAN button.> This gives the Geocentric Latitude in Integer and Decimal) = 11.57411985> Keep it on the screen.> Step 3: Press Deg-Min-Sec button.> This gives the Geocentric Latitude in Deg.Min.Sec. ) = 11.34.26.83 N> to round off = 11.34..27 N > ------------ --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- ---------> Geocentric Latitude = Press TAN, then Press Geographical Lat (in DMS) > x by 0.99330546> Press Shift , then press TAN. > = in Integer-Decimal> Press DMS> = in Deg-Min-Sec. > ------------ --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- - > * Please check this out at the shop before you buy the calculator.> ------------ --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- ---------> With thanks and warm regards,> > Mohan Kumar.R.> Scientific Astrologer & Spoken English Tutor> Advanced Stellar Astrology Research Academy (KP based)> 219/84, Moongapadi St.,Gugai, SALEM - 636 006> Cell: 99443-07025> > --- On Tue, 8/26/08, tw853 tw853 > wrote:> > tw853 tw853 >> Re: converting geographic to geocentric lattitudes> @gro ups.com> Tuesday, August 26, 2008, 6:14 PM> > > > > Geocentric Correction (KP for Beginners- Part 2, KPE-Zine)> > 12. In the calculation of cuspal positions, these days there is a > tendency of preferring Geocentric latitude of a place of birth other > than Geographic latitude assuming for better accuracy. "Geocentric > Correction" is supported by many SWs like KPAstro 3.0, Astraura, > Jyotishya Deepika, Solar Fire. It is to note that the ephemeris > gives the Geocentric positions of the planets (i.e. the positions > are as seen form the center of the earth), and the charts with the > common indication of Geocentric are generally Geocentric for > planetary positions only but Geographic for cuspal positions. It is > supposed to be the same with the example charts in the KP Readers as > it is said that Guruji Sri K.S. Krishnamurti used Geographic > latitude only. So it is better to mention "Geocentric Correction", > if it is used, to make it clear in comparing with the commonly used > Geographic cuspal positions. > > 13. In using the "Geocentric Correction", the Geographic latitude of > birth place given by the atlas is to be converted into the > Geocentric latitude by subtracting the minute for correction given > in the Table 14. The minute for correction increases up to around 11 > minutes till 45 latitude and then declines. As 1 min roughly covers > 1.8 km, this maximum 11 min would cover about 20 km. This difference > is not much with compared to the differences in Ayanamsa values to > change the sub-lords except in the border line cases. However, the > better accuracy is preferable like taking the correct suburb of > birth in the case of big cities like Kolkata, Delhi, Mumbai and > Chennai. A short article will be presented on different views on > which one, Geographic or Geocentric latitude, is more accurate. > > Table 14: Geocentric Correction to Latitudes> (Subtract from Geographic Latitudes) > > GL......CN.. ....GL> 0 0.0 90> 1 0.4 89> 2 0.8 88> 3 1.2 87> 4 1.6 86> 5 2.0 85> 6 2.4 84> 7 2.8 83> 8 3.2 82> 9 3.6 81> 10 3.9 80> 11 4.3 79> 12 4.7 78> 13 5.0 77> 14 5.4 76> 15 5.8 75> 16 6.1 74> 17 6.4 73> 18 6.8 72> 19 7.1 71> 20 7.4 70> 21 7.7 69> 22 8.0 68> 23 8.3 67> 24 8.6 66> 25 8.8 65> 26 9.1 64> 27 9.3 63> 28 9.6 62> 29 9.8 61> 30 10.0 60> 31 10.2 59> 32 10.4 58> 33 10.6 57> 34 10.7 56> 35 10.8 55> 36 11.0 54> 37 11.1 53> 38 11.2 52> 39 11.3 51> 40 11.4 50> 41 11.4 49> 42 11.5 48> 43 11.5 47> 44 11.6 46> 45 11.6 45> > GL= Geographic Latitude in Degree > > CN= Correction in Minute > > 14. In the Example Chart 2, Geographic latitude 23N is converted > into Geocentric latitude 22N52 by subtracting 8min for 23deg as > given in Table 25. To get the cuspal position for 22N52 by > interpolation from the values for 22° N and 23° N, the cuspal > positions for 22° N are calculated as follows.> > @gro ups.com, "swami" swami@ wrote:> >> > "swamynathaniyer" swamynathaniyer@ .... > @gro ups.com> > converting geographic to geocentric > lattitudes> > Tuesday, August 26, 2008 1:59 PM > > I would like to do this conversion manually. No software with > me. How to do it, is my problem. ? Will somebody educate me in a > simple term? With basic mathematical calculations. NOT trigonometry > or Calculus etc., Expecting eagerly Swamynathan.> > > > Dear Swamynathaniyer ji,> > > > Since you are not using Software, for casting you may be using > Table of houses.> > Two tables are popular.1. Raphels 2. UTOH..> > In case You are using Raphels table of house it shows for > latitudes By name of city that falls at latitudes.> > In any case in olden days when we learned casting geocentric > sanskar was taught to be applied.> > For Each degree of Latitude we were given kala and vikla to be > deducted irrespective of It is North or south. It is in table form. > can be found in panchangs .> > For example For 27 Degree 9 kala and 22 vikla were deducted. to > get Geocentric latitude. UTOH gives 9 kala and 18 vikla.> > For it table is available in various panchangs also.> > In case you are using UTOH , table VI has got conversion sanskar > on page 198 > > Hope this helps.> > OM TAT SAT> >> > > > > > Download prohibited? No problem. CHAT from any browser, without download.>