Circumambulation through the Bounds Module

[ABer]

Hi there - update your software to include the latest version of the Circumambulation through the Bounds module:

Horoscope - Classical - Circumambulation through the Bounds: v. 1.51 - now includes choice of four bounds and one deg or naibod arc, helpfile improved and updated

From the Helpfile:

This module is designed to complement the Hellenistic, medieval and early modern period astrology modules in Planetdance.

The module calculates a list of primary directions of the ascendant through the bounds according to the method of Ptolemy. The Ptolemaic key may be used - one year of life for each degree that passes the midheaven. Alternatively the naibod key may be used which is 59 minutes, 8 seconds of arc per annum, which is equivalent to the average daily motion of the Sun.

The list of directions represents the rising of the bounds across the horizon for a period of hours after the birth. The algorithm converts this into equivalent years. Calculations are provided for up to 120 years of human life.

All directions are calculated 'in zodiaco'. This means that the bound cusp positions are taken to be the zodiacal degree (without latitude). However, the declination of the degree occupied by the bound cusp means that the time taken for the aspect to form may be more or less than number of ecliptic degrees between the two points suggests.

Primary directions are a very time sensitive method of forecasting. If the birthtime is inaccurate by four minutes, the directions to the angles will be out by +/- year.

The method may be used to rectify a chart where the birth time is accurately known. However, if the birthtime is not accurately known, alternative methods of forecasting should be preferred.

For further reference, please see Martin Gansten (2009) Primary Directions: Astrology's Old Master Technique. The Wessex Astrologer, Bournemouth.

All algorithms are adapted from Gansten's book.

The text used for the list of directions may be enlarged or reduced by right-clicking in the text frame and selecting fontsize+ or fontsize-.

[Sindy]

Thank you very much for this feature!

[ABer]

Thanks Sindy. It's a good development of this script. I'm still working on the medieval module. It's proved rather complex! I hope it won't be too long until I can release it.

All the best. Ed

[Mercurio0311]

CLASSICAL - CIRCUMAMBULATION THROUGH THE BOUNDS
Asc displacement error.
when I use sidereal zodiac (Bhasin)
I am investigating the use of Asc Directed through Egyptian Terms.
Comparing PlanetDance with two other software, the results do not agree.
In the attached image I underlined the entry of the Asc in the different signs as an example of what I am saying.
Would it be possible to correct that error?
Thank you!!!

[Jean]

This is Ed's work, he will surely come and answer you.

[ABer]

Thanks for your feedback. I will take a look at this. However I'm very busy at the moment so please be patient! Ed

[ABer]

HI there - do you know if this is correct if the tropical zodiac is used?

See attached screenshot.

By the way, you have Enfield at 00E05, when your other programs are showing 00W05. It doesn't affect this issue but you might want to change your places database for maximum accuracy.

Thanks. Ed

[Mercurio0311]

Hello good day!!!
I corrected the Cordenadas. Thank you!!
Using Zodiac Tropical, Planet Dance is totally correct.
The problem only occurs when switching to the Sidereal zodiac.

Thanks again for taking care of the problem!!!

[ABer]

Hi there - thanks for the confirmation. I'm trying to fix the problem but it's an odd bug. I'll keep you up to date. Ed

[ABer]

Hi there - can you let me know if this happens with all sidereal charts, and with different ayanamsas. Thanks. Ed

[Mercurio0311]

I tried Chaplin's letter and Fagan's ayanamsa. The error persists, it's still there.
I also noticed that the calculation is wrong in the 'Ascensions in Years through the Bounds' window in the 'Ed Greek Horoscope' module. For example:
Chaplin's Jupiter (14°59 Sagittarius according to Fagan's Ayanamsa) in the Table of Ascensions. says that he enters Capricorn at 18.90 Years, when in fact he does so at approximately 13 years. And then at age 32 (approximately) he enters Aquarius. In the PlanetDance chart he says that he enters Aquarius at 45.52 years.
The Ascension Time of Aquarius for London is about 17.20

Undoubtedly the error is when doing the calculations on the Sidereal zodiac, the Sign of Leo is not the same as the Constellation of Leo, there is a 23° phase shift. Still I wish the same method could be used with the Sidereal zodiac. (There are some Valens cards that correspond to a sidereal zodiac and I would like to investigate his methods using such a zodiac)
Sorry for my bad command of the English language, Google and its translator are helping me 

[ABer]

Hi there - I think I've discovered the problem, but it's not a bug in the coding. The issue is that simply subtracting the ayanamsa value from the asc and mc means that the methodology I'm using, which works for the tropical zodiac, doesn't work with the sidereal. I've taken the method from Martin Gansten's book on primary directions, and it clearly works for the tropical zodiac. It's difficult to explain, but the following might help:

Sidereal angles for Winehouse's chart are Asc 25 TA 14 and MC 19 CP 28. However, if you make a chart using the tropical zodiac using the MC 19 CP 28, the ascendant is 15 TA 31. So the right ascension of the MC at this longitude is associated with a rising degree of 15 TA 31 at this latitude, not a rising degree of 25 TA 14. The issue is that there is simply not an equivalence between subtracting the ayanamsa from the angles and using the actual values for right ascension and so on. To me it seems that mixing a methodology like this with two different zodiacs is potentially flawed.

Put simply, the relationship between the MC and ascendant when the sidereal zodiac is used, is an artificial one, defined solely by the subtraction of the ayanamsa, rather than anything astronomical. This seems problematic to me when the method that is being deployed, the rising of the bounds, is based on the principle of ascensions which is underpinned by astronomy.

If I'm honest, I don't know how the values for the ascensions in the other software are calculated, because they must be using a different methodology from Gansten.

I'm not really sure whether I want to pursue this because the modules are designed for use with the tropical zodiac by default. I will mull it over but I wonder if it's worth the effort if you have access to software that already does this for you.

Sorry that I don't have an easy answer for you.

[Mercurio0311]

I understand, and I know that what I'm proposing is a lot of work (what you say about Gansten strikes me, since he is a defender of the sidereal zodiac, anyway I'm not up to date with the mathematical questions... So sure you are right).
My interest in the sidereal zodiac arose as a result of maps clearly calculated on such a system, Maps that can be found in the books of Valens and Doroteo for example, and they (especially the first), used the method of Ascension Times.
Anyway, I thank you for your time and the improvements that PlanetDance improves day by day.
As a curiosity I leave the link of an article (I have more, but they are in Spanish) by Deborah Houlding where recent research shows that a map in Dorotheus is clearly calculated on the sidereal zodiac.

What is interesting and what comes to the subject, is from page 7 of the pdf

http://www.skyscript.co.uk/dorotheus3notes.pdf

[ABer]

Thanks for your reply. I will keep thinking about this. However I have some other projects that I would like to prioritise. Thanks for the link. My interpretation of the text tends to support the conclusions I have reached. Whatever is being done probably does not involve a methodology using calculations of right ascension and oblique ascension (see the paragraph at the foot of p. 7 and footnote 27). My guess is that the classical author referred to in Deb Houlding's text was using a 'rule of thumb' approach which was probably accurate enough for his purposes. (In my view precision is an over-rated concept in astrology.)

The other thought that I have is that these authors might have been using some sort of sidereal zodiac, but weren't using an adjustment ('ayanamsa') of 23-26 degrees, It is likely that the difference between the two zodiacs would have perhaps been a couple of degrees. Given the levels of precision being employed by the classical author in this article, it is not unreasonable to suggest that the differences between a tropical and sidereal calculation would not have been noticeable, especially when translated into the approximate ages at which the ascendant entered the various bounds.

Of course we now have to contend with a highly divergent pair of zodiacs and this throws up the problems that I have highlighted in trying to sort out this apparent 'bug' in the module. As the two zodiacs continue to diverge and the ayanamsa increases, the issue will just be compounded.

There is potentially a way to resolve this, but it would involve calculating the ascensions for the bounds in the tropical zodiac and then 'overlaying' these values onto the sidereal degrees. However it is methodologically inconsistent because it won't bear any relationship to the actual astronomical situation obtaining at the moment for which the chart is cast. It would be interesting to see if values calculated this way agree with the values worked out in your other software. It all looks a bit muddled to me.

For what it's worth, I gave up exploring the sidereal zodiac after reading Fagan and Firebrace's A Primer of Sidereal Astrology. The only evidence they use to support their case is that of a young girl aged 10 years 5 months. This seems suspicious to me because over the course of that period of time precession will have made little difference to most of the timing of the astrological significations they describe. I think their case would have been more compelling had they used someone who's age was 70+ years where precession would have made a much more noticeable difference.

Anyway, thanks for your kind words about Planetdance. It's always good to hear positive feedback.

[ABer]

Hi again - I'm gradually piecing this together. It seems that to calculate ascensional times using the sidereal zodiac, you have to add the value of the ayanamsa to 0 Aries. I have been cross checking with Petr's Astroseek site and I now get ascensional times close to his data. See attached. I still think this is an incoherent marriage of methodologies but I will keep exploring this for you. To see the comparison see the column 'Degrees over MC` in the Planetdance screenshot and the 'Rising Times' column in Petr's data.

One thing to note is that the symmetry of rising times about the equinoxes and solstices does not persist when the sidereal zodiac is used which immediately strikes me as odd.

All the best. Ed