Western astrology is based mainly upon the construction of a horoscope , which is a map or ''chart'' of the heavens at a particular moment. The moment chosen is the beginning of the existence of the subject of the horoscope, as it is believed that the subject will carry with it the pattern of the heavens from that moment throughout its life. The most common form of horoscope is the natal chart based on the moment of a person's birth; though in theory a horoscope can be drawn up for the beginning of anything, from a business enterprise to the foundation of a nation state.
Interpretation
In Western horoscopic astrology the interpretation of a horoscope is governed by:*The position of the planets in the astrological signs of the zodiac,
*The position of the planets in the houses of the horoscope,
*The position of the primary angles of the horoscope, namely the horizon line (called the ascendant/descendant axis), and the prime vertical line (called the zenith/midheaven and nadir/imum coeli axis),
*The angles formed by the planets relative to each other and the primary angles, called aspects
*The position of deduced astronomical entities, such as the Lunar nodes.
Some astrologers also use the position of various mathematical points such as the Arabic parts.
The primary angles
There are four primary angles in the horoscope (though the cusps of the houses are often included as important angles by some astrologers).
* - The ascendant or ''rising sign'' is the eastern point where the ecliptic and horizon intersect. During the course of a day, because of the Earth's rotation, the entire circle of the ecliptic will pass through the ascendant and will be advanced by about 1°. This provides us with the term ''rising sign, which is the sign of the zodiac that was rising in the east at the exact time that the horoscope or natal chart is calculated. In creating a horoscope the ascendant is traditionally placed as the left-hand side point of the chart. In most house systems the ascendant lies on the cusp of the 1st house of the horoscope.
The ascendant is generally considered the most important and personalized angle in the horoscope by the vast majority of astrologers. It signifies a person's awakening consciousness, in the same way that the Sun's appearance on the eastern horizon signifies the dawn of a new day. Due to the fact that the ascendant is specific to a particular time and place, it signifies the individual environment and conditioning that a person receives during their upbringing, and also the circumstances of their childhood. For this reason, the ascendant is also concerned with how a person has learned to present him or herself to the world, especially in public and in impersonal situations.
The opposite point to the ascendant in the west is the descendant , which denotes how a person reacts in their relationships with others. It also show the kind of person we are likely to be attracted to, and our ability to form romantic attachments. In most house systems the descendant lies on the cusp of the 7th house of the horoscope.
* - The midheaven or ''medium coeli'' is the point on the ecliptic that is furthest above the plane of the horizon. For events occurring where the planes of the ecliptic and the horizon coincide, the limiting position for these points is located 90° from the ascendant. For astrologers, the midheaven traditionally indicates a person's career, status, aim in life, aspirations, public reputation, and life goal. In ''quadrant house'' systems the midheaven lies on the cusp of the 10th house of the horoscope.
The opposite point to the midheaven is known as the imum coeli. For astrologers the nadir or IC traditionally indicates the circumstances at the beginning and end of a person's life, their parents and the parental home, and their own domestic life. In ''quadrant house'' systems it lies on the cusp of the 4th house of the horoscope.
The houses
The horoscope is divided by astrologers into twelve portions called the houses. The houses of the horoscope are interpreted as being twelve different spheres of life or activity. There are various ways of calculating the houses in the horoscope or birth chart. However, there is no dispute about their meanings, and the twelve houses
Many modern astrologers assume that the houses relate to their corresponding signs, i.e. that the first house has a natural affinity with the first sign, Aries, and so on.
Aspects
The aspects are the angles the planets make to each other in the horoscope, and also to the ascendant, midheaven, descendant and nadir. The aspects are measured by the angular distance along the ecliptic in degrees and minutes of celestial longitude between two points, as viewed from the earth. They indicate focal points in the horoscope where the energies involved are given extra emphasis. The more exact the angle, the more powerful the aspect, although an allowance of a few degrees each side of the aspect called an ''orb'' is allowed for interpretation. The following are the aspects in order of importance
* - Conjunction 0° (orb ±8°). The conjunction is a major point in the chart, giving strong emphasis to the planets involved. The planets will act together to outside stimulus and act on each other.
* - Opposition 180° (orb ±8°). The opposition is indicative of tension, conflict and confrontation, due to the polarity between the two elements involved. Stress arises when one is used over the other, causing an imbalance; but the opposition can work well if the two parts of the aspect are made to complement each other in a synthesis.
* - Trine 120°(orb ±8°). The trine indicates harmony, and ease of expression, with the two elements reinforcing each other. The trine is a source of artistic and creative talent, but can be a 'line of least resistance' to a person of weak character.
* - Square 90°(orb ±8°). The square indicates frustration, inhibitions, disruption and inner conflict, but can become a source of energy and activation to a person determined to overcome limitations.
* - Sextile 60°(orb ±6°). The sextile is similar to the trine, but of less significance. It indicates ease of communication between the two elements involved, with compatibility and harmony between them.
* - Quincunx 150°(orb ±3°). The quincunx indicates difficulty and stress, due to incompatible elements being forced together. It can mean an area of self neglect in a person's life (especially health), or obligations being forced on a person. The quincunx can vary from minor to quite major in impact.
* - Semisextile 30° (orb ±2°). Slight in effect. Indicates an area of life where a conscious effort to be positive will have to be made.
* - Semisquare 45°(orb ±2°). Indicates somewhat difficult circumstance. Similar in effect to semisextile.
* - Sesquiquadrate 135°(orb ±2°). Indicates somewhat stressful conditions. Similar to semisextile.
* - Quintile 72° (orb ±2°). Slight in effect. Indicates talent and vaguely fortunate circumstances.
* - Biquintile 144° (orb ±2°). Slight in effect. Indicates talent and vaguely fortunate circumstances.
* - Retrograde: A planet is retrograde when it appears to move backwards across the sky when seen from the earth, due to one planet moving more quickly relative to the other. Although it is not an aspect, some astrologers believe that it should be included for consideration in the chart. Planets which are retrograde in the natal chart are considered by them to be potential weak points.
