The zodiac

The zodiac

The zodiac is the belt or band of constellations through which the Sun, Moon, and planets transit across the sky. Astrologers noted these constellations and so attached a particular significance to them. Over time they developed the system of twelve signs of the zodiac, based on twelve of the constellations they considered to be particularly important. The Western and Indian zodiac signs have a common origin in the tradition of horoscopic astrology, and so are very similar in meaning. In China on the other hand, the development of the zodiac was different. Although the Chinese too have a system of twelve signs (named after animals), the Chinese zodiac refers to a pure calendrical cycle, as there are no equivalent constellations linked to it like the Western or Indian zodiacs. The common choice of twelve zodiac signs is understandable considering the interaction of the Sun and Moon was central to all forms of astrology. Twelve cycles of the Moon — the months — coincided with one solar year, making twelve a natural choice.
The majority of Western astrologers base their work on the tropical zodiac which divides the sky into twelve equal segments of 30 degrees each, beginning with the first point of Aries, the point where the line of the earth's celestial equator and the ecliptic (the Sun's path through the sky) meet at the northern hemisphere spring equinox. Due to the precession of the equinoxes, the slow changing of the way Earth rotates in space, the zodiacal signs in this system bear no relation to the constellations of the same name but stay aligned to the months and seasons.
Practitioners of the Indian astrological tradition and a minority of Western astrologers use the sidereal zodiac. This zodiac uses the same evenly divided ecliptic but approximately stays aligned to the positions of the observable constellations with the same name as the zodiacal signs. The sidereal zodiac differs from the tropical zodiac by an offset called the ayanamsa which steadily increases as the equinoxes drift further.

Horoscopic astrology

Horoscopic astrology is a system that was developed in the Mediterranean region and specifically Hellenistic Egypt around the late 2nd or early 1st century BCE.[15] The tradition deals with two-dimensional diagrams of the heavens, or horoscopes, created for specific moments in time. The diagram is then used to interpret the inherent meaning underlying the alignment of celestial bodies at that moment based on a specific set of rules and guidelines. A horoscope was calculated normally for the moment of an individual's birth, or at the beginning of an enterprise or event, because the alignments of the heavens at that moment were thought to determine the nature of the subject in question. One of the defining characteristics of this form of astrology that makes it distinct from other traditions is the computation of the degree of the Eastern horizon rising against the backdrop of the ecliptic at the specific moment under examination, otherwise known as the ascendant. Horoscopic astrology has been the most influential and widespread form of astrology across the world, especially in Africa, India, Europe, and the Middle East, and there are several major traditions of horoscopic astrology whose origins are Hellenistic, including Indian, Medieval, and most other modern Western traditions of astrology.

The horoscope

Central to horoscopic astrology and its branches is the calculation of the horoscope or astrological chart. This two-dimensional diagrammatic representation shows the celestial bodies' apparent positions in the heavens from the vantage of a location on Earth at a given time and place. The horoscope is also divided into twelve different celestial houses which govern different areas of life. Calculations performed in casting a horoscope involve arithmetic and simple geometry which serve to locate the apparent position of heavenly bodies on desired dates and times based on astronomical tables. In ancient Hellenistic astrology the ascendant demarcated the first celestial house of a horoscope. The word for the ascendant in Greek was horoskopos from which horoscope derives. In modern times, the word has come to refer to the astrological chart as a whole.

Branches of horoscopic astrology

Traditions of horoscopic astrology can be divided into four branches which are directed towards specific subjects or purposes. Often these branches use a unique set of techniques or a different application of the core principles of the system to a different area. Many other subsets and applications of astrology are derived from these four fundamental branches.
Natal astrology, the study of a person's natal chart to gain information about the individual and his/her life experience.
Katarchic astrology, which includes both electional and event astrology. The former uses astrology to determine the most auspicious moment to begin an enterprise or undertaking, and the latter to understand everything about an event from the time at which it took place.
Horary astrology, used to answer a specific question by studying the chart of the moment the question is posed to an astrologer.
Mundane or world astrology, the application of astrology to world events, including weather, earthquakes, and the rise and fall of empires or religions.