HOUSE DIVISION

Signs and Houses are not the same. Signs are twelve-fold divisions

of the zodiac which is a belt of space along the ecliptic extending

to 8° on either side. Planets traverse through the signs at

different speeds in their own orbits slightly inclined to the ecliptic.

Houses are divisions of space below and above the horizon of a

place. We know that the earth rotates and also revolves round the

Sun. Because of the diurnal motion of the earth, the planets

appear to rise in the eastern horizon of the place, reach the mid-

heaven and set in the West.                                

                                   

 

The above picture shows the principle of house division.

The horizontal line (East to West) is the horizon of the place. The

inner circle is the ecliptic. Z is the zenith, the point above head in

any particular locality. It is not the Medium Coeli which is South of

it (the M.C. is the highest point the Sun reaches on any particular

day). The sun and the other planets travel along the ecliptic.

The houses are marked 1, 2, 3 etc. Houses 1 to 6 are below the

horizon (night houses). Houses 7 to 12 are above the horizon ( day

houses ).

The Ascendant, generally, is the point where the ecliptic cuts the

horizon of the place.

As the pole of the earth is inclined at 23 1/2° to the ecliptic and

the earth is elliptical in shape, at any given moment, the heavens

portray different pictures at different places.

There are various systems of house division, a discussion of which

is beyond the scope of this article. However we shall give a brief

account of the different house systems. They can be broadly

classified into three types, based on the Ecliptic, Time and Space.

To understand the principles behind the various systems of house

division, the following points must be borne in mind.

 

 

Definition of Terms

CELESTIAL SPHERE: The sphere formed by the extension of the space

surrounding the Earth.

CELESTIAL EQUATOR: A great circle parallel to the Earth's equator projected

into the celestial sphere along which right ascension is measured.

CO-LATITUDE: The complementary angle of the terrestrial latitude. The city

of Bangalore is located at 13° North terrestrial latitude; the co-latitude of

Bangalore is 77° (the angular distance of the place from the earth's

North Pole).

CO-EQUATOR: The mirror image of the earth's equator (the equator which is

mathematically associated with the co-latitude of a locality on the earth).

CO-POLAR AXIS CIRCLE: The great circle formed when the mathematics

used to derive the polar axis circle is mirrored from the Earth's poles,

rather than from the Earth's equator.                               

ECLIPTIC: That great circle of the celestial sphere which the Sun traces,

when seen from the Earth, in its annual motion.

EQUATORIAL SYSTEM: A sphere of space using the celestial equator as its

main central circle or equator.

GREAT CIRCLE: A circle contained within the celestial sphere which has as

its center the center point of the celestial sphere.

HOUR CIRCLE: A great circle which is perpendicular to the Celestial Equator

and which passes through a particular body in space.

CELESTIAL HORIZON: A great circle of the celestial sphere formed by the

projection of the horizon of a locality on the earth.

HOUSE CIRCLE: A great circle which has as its poles the North and South

points of Horizon and which is perpendicular to the Prime Vertical. 

LOCAL SIDEREAL TIME: The time calculated for a horoscope when a time of

event is added to the longitude correction, the time zone correction, the

acceleration, the delta T correction, and ephemeris.

MERIDIAN: A great circle of the Horizon system which passes through the

Zenith, the nadir, and the North and South points of the horizon.

ZENITH: The North Pole of the horizon system. The point of the horizon

system which is over your head.

NADIR: The South Pole of the Celestial Horizon, Opposite to the Zenith.

OBLIQUITY: The angle in space formed between the ecliptic and the

celestial equator. At present it is 23°-27" and is decreasing slowly with

time.

POLAR AXIS CIRCLE: A great circle which passes through the North and

South Poles of the Earth and the East and West points of the Horizon.

VERTICAL CIRCLE: A great circle perpendicular to the Horizon, passing

through the Zenith and the Nadir.

PRIME VERTICAL: A great circle which passes through the Zenith, the Nadir

and the East and West points of the Horizon of the place perpendicular to

the Meridian.

ZODIAC: A broad band of space of the celestial sphere extending to 8° on

either side of the ecliptic. This is like a window. The constellations lying

several light years away visible through this window

are taken for astrological considerations. The Zodiac is divided into 12 solar

mansions starting from Aries and 27 lunar mansions with the asterism

Ashwini as the beginning.

 

Earth System Equatorial Sys. Ecliptic System Horizon

System

North & South Poles Celestial Poles Ecliptic Poles Zenith; Nadir

Equator Celestial Equator Ecliptic Horizon

Latitude Declination Zodiacal Latitude Altitude

Co-Latitude Polar Distance Polar Elevation Zenith

Distance

Parallels of Latitude,

or Latitude Circles

Diurnal Circles Latitude Circles Altitude

Circles

Meridians Hour Circles Longitude Circles Vertical

Circles

Longitude Right Ascension Zodiacal Longitude Azimuth

Angle

Greenwich Meridian Hour Circle of Aries Local Meridian Prime

Vertical

 

 

 

 

 

 

 

 

 

 

 

 

 Ecliptic based house systems

I. EQUAL HOUSES 

Sensitive Points

 

    

 Its opposite Intersection of

the Ecliptic and the

Ascendant Descendant Horizon

Medium Coile

(MC)

 Imum Coile (IC) Meridian

Equatorial ASC Equatorial DSC Polar Axis

Vertex Equatorial

Ascendant

Prime Vertical

Co-Ascendant Co-Descendant Co-Equator

Polar Ascendant Polar Descendant Co-Polar Axis Circle

The Vernal

Equinox

 The Autumnal

Equinox

Equator

Moon's North

Node

South Node  Plane of the

Moon's Orbit

a) The intersection of the horizon and the ecliptic is taken as the

ascendant. The other houses are 30° in length, starting from the

ascendant along the ecliptic. Note that the cusp of the X house is not

the Meridian Coile. 

 

b) The MC is taken as the reference point and the other houses are equal in

measure along the ecliptic. Note that the ascendant is not the intersection

of the horizon  and the ecliptic.

c) The Whole Sign system: The sign which contains the ascendant is taken

as a whole and this is the first house. The starting point of the house is 0°

of the sign. The Whole Sign system is the one followed by most

traditional astrologers.

II. QUADRANT SYSTEMS

The arc of the ascendant and MC (cusp of the X) is taken as the basis and

other cusps are determined. For example Porphyry trisects this arc to get

the cusps of house XII and XI. Cusps of houses II and III are got

by trisecting the arc of the ascendant and the IC. Cusps of other houses lie

opposite to these houses.

TIME BASED SYSTEMS

The Koch house system, also known as the Birthplace system, is a time-

based system introduced by Walter Koch. For cusps above the horizon: the

semi-diurnal arc is trisected; then, altitude circles (small circles parallel to

the horizon) are drawn through the points of trisection; the cusps are

determined by the intersections of these  altitude circles with the ecliptic.

For cusps below the horizon: the semi-nocturnal arc is used. The MC and

ascendant are the same respectively, as in the quadrant systems.

This system fails in high latitudes.

The Placidian, Topocentric, Regiomontanus are examples of some more

Time based house systems.

SPACE BASED HOUSE SYSTEMS

Meridian House System

The Meridian house system was proposed by the Australian astrologer

Zariel (David Cope). This system is also called the Equatorial House System.

Equal mid-heaven houses on the equator are projected by meridian circles

of right ascension to the ecliptic. Each house is exactly two sidereal hours

long. The MC is the cusp of the tenth house and the Equatorial Ascendant is

the cusp of the first house.

Each house system has its own merits and demerits. Some systems do not

work on high latitudes; some others are based on complex and fascinating

mathematical factors but not much of astrological relevance.

It is one's experience and purpose which could decide on which system is

the best.

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