Primary Directions Tests and Comparisons – tropical and sidereal.
Updated 3rd September 2025.
PD = Primary Directions
Bounds = Terms
Many parts of this post were written before AC for iPhone was released. Note that although most AC screenshots are for the iPad they apply to the iPhone and Mac too as they share the same underlying code.
All images/designs/procedures subject to change without notice.
Here’s an excellent introduction to Primary Directions.
Astrological Predictive Techniques | Primary Directions | 1. Ascensions and Bounds
Whitney Houston’s Chart and Primary Directions through the Bounds/Terms (iPad/Mac – same results for iPhone) – see Seven Stars Astrology link above.
Whitney Housten Chart and PD directions
How the Technique Works (AI generated)
- 1. The “Primary Motion”:
This refers to the Earth’s daily rotation, which causes the sky (including planets, stars, and zodiac signs) to appear to move around a place of observation.
- 2. The “Direction” of the Point:
The Ascendant, the Sun, Moon, or another significant point in the natal chart is considered to be in “primary” motion, meaning it moves against the direction of the Earth’s daily rotation, with the motion calibrated so that one degree of movement corresponds to one year of life.
- 3. The “Bounds” (or Terms):
Each zodiac sign is divided into five unequal sections called “bounds” or “terms”.These terms are ruled by one of the traditional planets (Mars, Mercury, Venus, Jupiter, or Saturn), which is called the Distributor.
- 4. The “Partner”:
As the directed point moves, it will eventually make an aspect (like a conjunction, square, or opposition) or join another planet, which is called the Partner.
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5. Interpreting the Period:
- Distributor: The planet ruling the bound provides the overall theme and nature of the period, governing the affairs related to the directed point.
- Partner: The Partner planet indicates specific people, events, or activities that will manifest within the theme set by the Distributor.
- Distributor: The planet ruling the bound provides the overall theme and nature of the period, governing the affairs related to the directed point.
- Predicting Major Life Phases:
By observing the sequence of Distributors and Partners, astrologers can identify major life periods and phases, such as periods of career focus, relationship changes, or significant life events.
- Connecting Natal Chart Potentials to Life Events:The technique links potential events indicated in a birth chart to specific years of a person’s life.
This post shows AC’s primary direction calculations in comparison with :
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Valens (Mac)
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Morinus (Windows)
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Astro.com (internet)
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Astro Gold ver 9 (Windows)
Note Valens and Morinus invariably agree in their results as Valens is a slimmed-down version of Morinus.
Antiscia
Example Chart: Winston Churchill: Tropical, Mundane. Antiscia. iPad/Mac – ver 3.35, iPhone ver 1.38
“A” prefixed to promissor = Antiscia
“CA” prefixed to promissor = Contra-Antiscia
Note that all antiscia aspects are conjunctions even when contra-antiscia aspects are shown. Enabling (by a tick) the opposition aspect from the Aspect table has no effect on the displayed antiscia aspects.
PD with Antiscia aspects – Churchill #1
PD with Antiscia and Contra aspects – Churchill #1
PD with Antiscia aspects – Churchill #2
PD with Antiscia and Contra aspects – Churchill #2
For comparison: Morinus – Churchill tropical antiscia aspects Primary Directions mundane example
Morinus Churchill tropical antiscia aspects Primary Directions mundane example
iPhone
PD with Antiscia and Contra aspects – Churchill – iPhone
Settings
Antiscia PD Settings for Results table
Note: Lat and long adjusted to Morinus’ lat and long for Churchill.
Primary Directions through the bounds/terms
Example Chart: Winston Churchill: Sidereal. Placidus cusps, Egyptian Terms/Bounds, Zodiacal.
Terms to Asc.
AC Churchill Sidereal Terms to Asc Primary Directions zodiacal
AC Churchill Sidereal Terms to Asc Primary Directions zodiacal #2
Morinus Churchill Sidereal Terms to Asc Primary Directions zodiacal
Example Chart: King Charles III, aka Prince Charles: Tropical. Placidus cusps
Note that all King Charles III charts have their lat and long adjusted to match the Astro.com chart so that comparisons are geographically valid.
AC Chart
AC King Charles III natal
Solar Fire Chart
Solar Fire King Charles natal
Speculum (natal) comparison (especially for Asc, MC), with lat and longitude as per astro.com, 51°N30’00” 00°W10’00” :
Astrodatabank
Valens speculum
Valens – Speculum King Charles
AstroConnexions Speculum
AC – Speculum King Charles
Primary Direction, Saturn Trine MC, promissor no latitude, calculation results comparison
Valens results
Valens King Charles Primary Direction Saturn Trine MC
AC results
Primary Directions King Charles III
Primary Direction, Saturn Trine MC, with promissor latitude, calculation results comparison
AC results
Primary Directions King Charles III – Promissor
Valens results
Valens Saturn trine MC King Charles with Lat Naibod key
Latest AC PD view
Latest AC PD
Promissor’s directed to the ASC. No latitude. Added 39 secs to birth date
AC
Aspects to the ASC results
Morinus (MS Windows) comparison:
Morinus King Charles aspects to the ASC no latitude
Moon aspects to King Charles III – direct and converse
AC King Charles PDs Results Moon aspects to ASC
Valens results
Valens King Charles PDs Results Moon aspects to ASC
AC latest PD view
Interplanetary PD aspects – Tropical
Valens PD Mercury aspects to Mars – Einstein
Valens PD Mercury aspects to Mars Einstein
AC Mercury aspects to Mars – Einstein
AC PD Mercury aspects to Mars Einstein
PD Terms/Bounds as Promissors to ASC
Einstein PD terms to Asc – Morinus (Windows) – Direct
AC Einstein PD Terms to Asc – Direct
AC Einstein Terms to Asc
Einstein PD terms to Asc – Morinus (Windows) – Converse
Morinus Einstein tropical Terms to Asc converse
AC Einstein Terms to Asc – Converse
AC Einstein Terms to Asc PD aspects
AC Einstein Terms to Asc PD aspects – more
Sidereal Examples, Sassanian ayanamsha
AC Allen Ginsberg Sidereal PD terms to Asc and Desc
Terms – sidereal Ginsberg
Morinus – Ginsberg Sidereal PD terms to Asc and Desc
Morinus Ginsberg Sidereal Terms to Asc sass
Calculating Terms as Promissors – tropical. for King Charts III.
If the terms are not shown in the chart:
Show terms in the chart
Show terms
Terms wheel choice
Results:
Terms to Asc results
Sidereal Interplanetary Aspects, Sassanian ayanamsha
King Charles III, Jupiter aspecting Moon
AC King Charles III planet to planet Jupiter Moon Sidereal
Morinus results
Morinus King Charles III planet to planet Jupiter Moon Sidereal
Primary Directions. Placidus semi-arc zodiacal, fixed stars as promissors
From AC ver 3.29, AC for iPhone ver 1.34
AC Churchill Fixed Stars to Asc, Mc Tropical
Comparison with Morinus
Primary Directions Mundane Promissor and Significator for South Node.
Solar Fire Mercury Churchill to true node, asc, mc Primary Directions Mundane Direct
AC Mercury Churchill to true node, asc, mc Primary Directions Mundane Direct
Comparison: Solar Fire Gold ver 9.029 vs AC Mundane Direct aspects to Asc
Please note that the following will apply to the iPad as the code is the same, although the UI is different.
Comparison Solar Fire Gold ver 9.029 vs AC Direct mundane aspects to asc
Comparison Solar Fire Gold ver 9.029 vs Morinus vs AC Direct Mars Sun Mundane aspects to the Sun
Comparison Solar Fire Gold ver 9.029 vs Morinus vs AC Direct Mars Sun mundane aspects to the asc
Rectification – Comparison – Morinus vs AC, Mundane.
Note: if changing from Zodiacal aspects to Mundane aspects or vice versa when using rectification you must start again by changing the chart from Transit to Natal. This only applies to the rectification result.
iPhone model: XR
Al Pacino chart
Morinus rectif mundane moon sq mercury
AC rectif mundane moon sq mercury
Rectification by 5 minutes
Morinus rectif mundane moon sq mercury plus 5 mins
AC rectif mundane moon sq mercury plus 5 mins
Adding 10 seconds
Morinus rectif mundane moon sq mercury plus 10 secs
AC rectif mundane moon sq mercury plus 10 secs