Houses in Polar Zone

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Calculations of house cusps in Polar Zones is known problem. Here is one point, which seems insufficiently taked into account. I sent some postings to alt.astrology to clarify situation. Here is copy of my last posting to alt.astrology, also some illustrations to this problem.

I wrote earlier to newsgroup about this problem. It seems to be
clear now. 

Look situation where we placed in Polar Zone in summer in midnight 
(or in winter in midday - result is same). Outside Polar Zone all 
is OK. If we increase latitude, we will find point, where Zenit-Nadir 
line is parallel to Ecliptic axis, that mean, local horizon match 
Ecliptic. If we increase latitude more, then MC, calculated by 
latitude-idependent formula, goes under local horizon. So I thought, 
that MC must be flipped in this case. 

I looked, how are calculated house cusps in this case in Astrolog 5.20 
and some other programs. Astrolog doesn't flips anything and for 
example Porphyry house cusps are mixed. "Astroloy for Windows" 
demoversion 2.2d by Halloran Software flips MC, but it reverses also 
direction of houses on Zodiac:  with increasing of house numbers 
zodiacal coordinates of house cusps decreases. I wasn't sure, which 
result is true and sent short message to alt.astrology to clarify 

John Halloran sent me letter, where draw my attention to point, that 
in this situation Ascendent is flipped - point on zodiac, which was 
ascending on lower latitudes, is now descending.

In Astrolog 5.20f I changed calculations of house cusps in Polar Zone. 
In situations described above MC-IC and ASC-DES was reverted, also 
houses order on zodiac (depending of house system). In other words, 
Astrolog 5.20f gives in such situations same result, than Halloran's 

After posting to alt.astrology about changes in Astrolog5.20f, 
I received letter from Jonathan C. Dunn, where he wrote, that Polar 
Zone MC is same as normal latitudes. Reason - definition of MC:
MC and IC are defined as points, formed by an intersection between 
Ecliptic and meridian. (quotation from letter follows):

:   1) Which point of ecliptic is highest relative to horizon?
:   2) Which point of ecliptic is at ITS OWN highest point relative 
:   to horizon?
:   #1, above, is not the MC, it is the zenith/birthplace, also 
:   called the  nonegesimal, the point always square to the ASC. 
:   No conceptualization of motion is required to conceptualize 
:   or understand it. You just run a line from the zenith down to 
:   the nearest point on the ecliptic. 
:   #2, above, is the MC. It is seldom square the ASC, and requires 
:   a calculation or conceptualization of daily motion of ecliptic 
:   points. The daily motion of each ecliptic point is an a small 
:   circle parallel to the equator. It turns out that to find the MC, 
:   you run a line from the zenith toward the nearest point on the 
:   equator. Whatever point on the ecliptic that this line passes 
:   through it the MC. A more complex notion.

So I found three points of view:

1. Original Astrolog calculations, where MC and (or) Asc aren't flipped.
Seems there named problem isn't taked into account at all.

2. Point of view of Halloran's Software. Flipped are both MC and Asc, and
houses order on Zodiac is reversed too.

3. Point of view of Jonathan C. Dunn. Flipped is only Asc. MC in Polar 
Zone is same, as at normal latitudes.

Discussion with Mr. Dunn cleared situation. If we use second definition 
(which is correct definition of MC), MC is same independent of latitude 
and DOESN'T flip in situations like above, but Ascendent flips. As result 
houses order on Zodiac isn't reverted. 

So I have made more changes in Astrolog 5.20f than necessary. Enough to 
flip only Ascndent in situations described above. In near future I hope 
to finish with version 5.20g where this problem will be solved.

Valentin Abramov

I finished changes in Astrolog 5.20g and sent corresponding message to alt.astrology. After this I received first reply to my posting about houses in polar zone. Here it is quoted.

Date sent:        Fri, 16 Aug 1996 19:30:36 -0700 (MST)
From:    (John A. Halloran)
Subject:          Re: MC in polar zone

Valentin et al.,

The grand master of modern astrology, Robert Hand, has already
thoroughly explored this subject of the ascendant, midheaven, and
vertex at extreme latitudes.

There are two ways to define and determine the ascending or descending
nodes of intersection between the great circle planes of the ecliptic
and the horizon and meridian circle.

I quote from Essays on Astrology, copyright 1982 Robert Hand.

"1.  The Ascendant

"A. According to Direction: The intersection of the ecliptic and
    rational horizon in the east, i.e., the eastern node.
"B. According to Up and Down: The ascending node of the ecliptic
    upon the rational horizon.

"2. The Midheaven

"A. According to Direction: The intersection of the meridian circle
    and the ecliptic in the south.  This is expressed by the old
    English term "southing," used for upper meridian passes.
"B. According to Up and Down: The intersection of the meridian circle
    and the ecliptic that is above the horizon, as opposed to the one
    below the horizon, which in normal latitudes is the Imum Coeli

The important point is that one be consistent in defining both the
Ascendant and Midheaven either according to Direction or according
to Up and Down.  One should not mix them.

You should obtain and read Hand's book yourself.  He concludes a
lengthy discussion by saying, "I always favor making the Ascendant
the ascending node of the ecliptic upon the horizon, and
concurrently making the Midheaven the ecliptic-meridian intercept
above the horizon.  This sometimes necessitates reversing some of
the other cusps, but these reversals do not violate the spirit of
the mathematical bases of any of these systems."

Robert Hand's conclusion is consistent with the practice of Swedish
astrologers and with the behavior of AstrolDeluxe for Windows and
Astrology for Windows.

John Halloran, Halloran Software
P.O. Box 75713, Los Angeles, CA 90075 U.S.A.

This letter cleared point of view of Halloran Software. Clear is also point of view of Jonathan C. Dunn. Unfortunately I haven't heard point of view of Walter D. Pullen, author of Astrolog, and I think, discussion isn't ended. Anyway, original Astrolog needs changes in this part.

Discussion really isn't ended. Because following postings and letters are relatively capacious, they are designed as separate text files, available from this page.

At 25th Aug. 1996 Per Dahlin posted an article to alt.astrology, where is explained flipping of both, ASC and MC. You can read this article, also my answer, posted at 29th Aug 1996, here.

Answer of Jonathan C. Dunn reached our news-server only at 30th aug. (posted to alt.astrology at 25th aug).

At 29th Aug 1996 I received letter from Jonathan C. Dunn (also posted to alt.astrology), where this question is discussed times more, also it is answer to letter from John A. Halloran.

So discussion in alt.astrology shows, that exist two points of view to flipping of MC -IC in circumpolar situations. (Asc - Des must be flipped in both cases).

1) MC is defined as upper culmination, then MC - IC aren't flipped, but MC is under horizon.
2) MC is defined as culmination above horizon and MC - IC are flipped.

In changed version 5.30a user can choose, flip then only Asc or also MC.


Graphics wheels of Astrolog 5.20 (original 5.30 gives same results):
Outside polar zone is chart normal. If we increase latitude over point, where Zenit-Nadir line is parallel to Ecliptic axis and don't flip anything, for example Porphyry house cusps positions are mixed.

I checked this point on three program - Astrolog 5.20, demoversion of "Astrowin" (AST4WIN) by Allen Edwall and demoversion of "Astrology for Windows" (version 2.2d) by Halloran Software. Demo pictures are made by Astrolog, here IC and MC aren't reversed, and house cusps are mixed. Same result is given by Astrowin. Halloran's Astrology reverses IC and MC, but it reverses also direction on Zodiac: with increasing of house numbers zodiacal coordinates of house cusps decreases. I wasn't sure, which result is true and sent short message to alt.astrology to clarify situation. Below are samples of printouts of programs.

Here are examples of results of changed astrolog with Porphyry houses (here are used outputs of older changed versions, but Astrolog 5.30a gives same results):

In polar zone are flipped both Asc and MC.

In polar zone is flipped only Asc.

Here are printouts of "Astrolog 5.20" and Halloran's "Astrology for Windows".
"Astrowin" demo version don't allows saving of outputs to file.

Astrolog 5.20 chart for Wed  3- 7-1985 21:55 (ST +3:00 GMT)
Polar zone  26:43E 80:00N
Body  Locat. Ret. Lati. Rul.      House  Rul. Veloc.    Porphyry Houses.
Sun : 11Can46   + 0:00' (-) [ 4th house] [-] +0.953  -  House cusp  1: 21Lib49
Moon: 28Cap28   - 4:50' (F) [ 2nd house] [e] +13.77  -  House cusp  2:  2Cap44
Merc:  5Leo54   + 1:10' (d) [ 4th house] [-] +1.395  -  House cusp  3: 13Pis39
Venu: 27Tau17   - 2:49' (R) [ 4th house] [-] +1.064  -  House cusp  4: 24Tau34
Mars: 16Can05   + 0:59' (d) [ 4th house] [d] +0.655  -  House cusp  5: 13Vir39
Jupi: 15Aqu40 R - 0:46' (-) [ 2nd house] [-] -0.087  -  House cusp  6:  2Cap44
Satu: 21Sco51 R + 2:15' (-) [ 1st house] [d] -0.034  -  House cusp  7: 21Ari49
Uran: 14Sag56 R - 0:02' (-) [ 1st house] [-] -0.035  -  House cusp  8:  2Can44
Nept:  1Cap58 R + 1:10' (-) [ 1st house] [-] -0.026  -  House cusp  9: 13Vir39
Plut:  1Sco57 R +16:53' (R) [ 1st house] [-] -0.004  -  House cusp 10: 24Sco34
Node: 15Tau25 R + 0:00' (-) [ 3rd house] [-] +0.053  -  House cusp 11: 13Pis39
Fort:  8Tau31   _______ (-) [ 3rd house] [d] ______  -  House cusp 12:  2Can44
                                                        Car Fix Mut TOT   +: 5
                                                     Fir  1   1   1   3   -:11
                                                     Ear  2   4   0   6   M: 0
                                                     Air  1   1   0   2   N:12
                                                     Wat  2   3   0   5   A: 8
                                                     TOT  6   9   1  16   D: 4
                                                                          <: 8

Unnamed Chart
03 July 1985   21:55:00
Polar Zone
Time Zone:  -03:00 (BAT)
Longitude:  026d E 43m
Latitude:  80d N 00m
Porphyry Houses
Tropical Zodiac
Mean Nodes

Table of Planets and Houses

Planet     Position   Planet     Position   Planet     Position   Planet     Position

Sun        11Can46    Mars       16Can06    Neptune    01Cap59 R  MNNode     15Tau25
Moon       28Cap28    Jupiter    15Aqu41 R  Pluto      01Sco56 R  MSNode     15Sco25
Mercury    05Leo54    Saturn     21Sco52 R  Ascendant  21Ari49    P_Fortune  08Sco31
Venus      27Tau17    Uranus     14Sag56 R  Midheaven  24Tau34    Chiron     11Gem27

House      Position   House      Position   House      Position   House      Position
First      21Ari49    Fourth     24Sco34    Seventh    21Lib49    Tenth      24Tau34
Second     02Pis44    Fifth      13Sco39    Eighth     02Vir44    Eleventh   13Tau39
Third      13Cap39    Sixth      02Sco44    Ninth      13Can39    Twelfth    02Tau44