In Western astrology, astrological signs are the twelve 30° sectors of the ecliptic, starting at the vernal equinox (one of the intersections of the ecliptic with the celestial equator), also known as the First Point of Aries. The order of the astrological signs is Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius and Pisces. Each sector was named for a constellation within it in the time of naming. These divisions were also used in scientific astronomy until the 19th century in some cases; see ecliptic coordinates.
The concept of the zodiac originated in Babylonian astrology, and was later influenced by Hellenistic culture. According to astrology, celestial phenomena relate to human activity on the principle of "as above, so below", so that the signs are held to represent characteristic modes of expression. Modern discoveries about the true nature of celestial objects have undermined the theoretical basis for assigning meaning to astrological signs, and empirical scientific investigation has shown that predictions and recommendations based on these systems are not accurate.:85;:424 Astrology is generally regarded as pseudoscience.
Various approaches to measuring and dividing the sky are currently used by differing systems of astrology, although the tradition of the Zodiac's names and symbols remain consistent. Western astrology measures from Equinox and Solstice points (points relating to equal, longest, and shortest days of the tropical year), while Jyoti?a or Vedic astrology measures along the equatorial plane (sidereal year). Precession results in Western astrology's zodiacal divisions not corresponding in the current era to the constellations that carry similar names, while Jyoti?a measurements still correspond with the background constellations.
Western astrology is a direct continuation of Hellenistic astrology as recorded by Ptolemy in the 2nd century. Hellenistic astrology in turn was partly based on concepts from Babylonian tradition. Specifically, the division of the ecliptic in twelve equal sectors is a Babylonian conceptual construction.
By the 4th century BC, Babylonian astronomy and its system of celestial omens influenced the culture of ancient Greece, as did the astronomy of Egypt by late 2nd century BC. This resulted, unlike the Mesopotamian tradition, in a strong focus on the birth chart of the individual and the creation of Horoscopic astrology, employing the use of the Ascendant (the rising degree of the ecliptic, at the time of birth), and of the twelve houses. Association of the astrological signs with Empedocles' four classical elements was another important development in the characterization of the twelve signs.
The body of the Hellenistic astrological tradition as it stood by the 2nd century is described in Ptolemy's Tetrabiblos. This is the seminal work for later astronomical tradition not only in the West but also in India and the Islamic sphere and has remained a reference for almost seventeen centuries as later traditions made few substantial changes to its core teachings.
The following table enumerates the twelve divisions of celestial longitude, with the Latin names (still widely used) and the English translation (gloss), which express the constellation they are named for. The longitude intervals, are treated as closed for the first endpoint (a) and open for the second (b) - for instance, 30° of longitude is the first point of Taurus, not part of Aries. The sign numbers, 0 through 11, are seen instead of the symbols in some astronomical works.
Any association of calendar dates with these signs only makes sense when referring to Sun sign astrology.
(a λ < b)
|Aries||1||0° to 30°||The Ram|
|Taurus||2||30° to 60°||The Bull|
|Gemini||3||60° to 90°||The Twins|
|Cancer||4||90° to 120°||The Crab|
|Leo||5||120° to 150°||The Lion|
|Virgo||6||150° to 180°||The Maiden|
|Libra||7||180° to 210°||The Scales|
|Scorpio||8||210° to 240°||The Scorpion|
|Sagittarius||9||240° to 270°||The Archer (Centaur)|
|Capricorn||10||270° to 300°||The Goat|
|Aquarius||11||300° to 330°||The Water-bearer|
|Pisces||12||330° to 360°||The Fish|
Empedocles, a fifth-century BC Greek philosopher, identified Fire, Earth, Air, and Water as elements. He explained the nature of the universe as an interaction of two opposing principles called love and strife manipulating the four elements, and stated that these four elements were all equal, of the same age, that each rules its own province, and each possesses its own individual character. Different mixtures of these elements produced the different natures of things. Empedocles said that those who were born with nearly equal proportions of the four elements are more intelligent and have the most exact perceptions.
Each sign is associated with one of the classical elements (fire, air, earth, and water), and these can also be grouped according to polarity (positive or negative): Fire and Air signs are considered positive signs while Water and Earth signs are considered negative signs. The four astrological elements are also considered as a direct equivalent to Hippocrates' personality types (sanguine = air; choleric = fire; melancholic = earth; phlegmatic = water). A modern approach looks at elements as "the energy substance of experience" and the next table tries to summarize their description through keywords.
|Fire||Assertion, drive, willpower||Aries, Leo, Sagittarius|
|Air||Communication, socialization, conceptualization||Gemini, Libra, Aquarius|
|Earth||Practicality, caution, material world||Taurus, Virgo, Capricorn|
|Water||Emotion, empathy, sensitivity||Cancer, Scorpio, Pisces|
This has gained such importance that some astrologers start their interpretation of a natal chart by studying the balance of elements shown by the position of planets and angles (especially the Sun's and Moon's ascendant signs).
|Cardinal||Action, dynamic, initiative, great force||Aries, Cancer, Libra, Capricorn|
|Fixed||Resistance to change, great willpower, inflexible||Taurus, Leo, Scorpio, Aquarius|
|Mutable||Adaptability, flexibility, resourcefulness||Gemini, Virgo, Sagittarius, Pisces|
The combination of element and modality provides a basic sign characterization. For instance, Capricorn is a cardinal earth sign, meaning that it is associated with action (cardinal modality) in the material world (earth element). The next table displays the twelve combinations of elements and modalities.
Rulership is the connection between planet and correlated sign and house. The conventional rulerships are as follows: Aries (Mars), Taurus (Venus), Gemini (Mercury), Cancer (Moon), Leo (Sun), Virgo (Mercury), Libra (Venus), Scorpio (Pluto), Sagittarius (Jupiter), Capricorn (Saturn), Aquarius (Uranus), and Pisces (Neptune).
Psychologically-oriented astrologers often believe that Uranus is the ruler or co-ruler of Aquarius instead of Saturn; Neptune is the ruler or co-ruler of Pisces instead of Jupiter, and, less often since its downgrade, that planetoid Pluto is the ruler or co-ruler of Scorpio instead of Mars. Some astrologers believe that the planetoid 2060 Chiron may be the ruler of Virgo, while other groups of modern astrologers claim that Ceres is the ruler of Taurus instead.
The following table shows both classical and modern rulerships. It also shows the approximate dates when the Sun is within these signs. By definition, Aries starts at the First Point of Aries which is the location of the Sun at the March equinox. The precise date of the Equinox varies from year to year but is always between 19 March and 21 March. The consequence is the start date of Aries and therefore the start date of all the other signs can change slightly from year to year.
|?||Aries||March 21 - April 19||Mars|
|?||Taurus||April 20 - May 20||Ceres (or)||Venus|
|?||Gemini||May 21 - June 20||Mercury|
|?||Cancer||June 21 - July 22||Moon|
|?||Leo||July 23 - August 22||Sun|
|?||Virgo||August 23 - September 22||Chiron (or)||Mercury|
|?||Libra||September 23 - October 22||Venus|
|?||Scorpio||October 23 - November 22||Pluto (or)||Mars|
|?||Sagittarius||November 23 - December 21||Jupiter|
|?||Capricorn||December 22 - January 19||Saturn|
|?||Aquarius||January 20 - February 18||Uranus||Saturn|
|?||Pisces||February 19 - March 20||Neptune||Jupiter|
The twelves signs each have opposites, resulting in six opposite couples. Fire and Air elements are opposites and Earth and Water elements are opposites. Spring signs are opposite to autumn ones, and winter signs are opposite to summer ones.
A traditional belief of astrology, known as essential dignity, is the idea that the Sun, Moon, and planets are more powerful and effective in some signs than others because the basic nature of both is held to be in harmony. By contrast, they are held to find some signs to be weak or difficult to operate in because their natures are thought to be in conflict. These categories are Dignity, Detriment, Exaltation, and Fall.
In traditional astrology, other levels of Dignity are recognised in addition to Rulership. These are known as Exaltation, Triplicity, Terms or bounds, and Face or Decan, which together are known as describing a planet's Essential dignity, the quality or ability of one's true nature.
The following table summarizes the positions described above:
|Planet (Symbol)||in dignity||in detriment||in exaltation||at fall|
|Mercury ()||Gemini and Virgo||Sagittarius and Pisces||Virgo||Pisces|
|Venus ()||Libra and Taurus||Aries and Scorpio||Pisces||Virgo|
|Mars ()||Aries and Scorpio||Libra and Taurus||Capricorn||Cancer|
|Jupiter ()||Sagittarius and Pisces||Gemini and Virgo||Cancer||Capricorn|
|Saturn ()||Capricorn and Aquarius||Cancer and Leo||Libra||Aries|
In addition to essential dignity, the traditional astrologer considers Accidental dignity of planets. This is placement by house in the chart under examination. Accidental dignity is the planet's "ability to act." So we might have, for example, Moon in Cancer, dignified by rulership, is placed in the 12th house it would have little scope to express its good nature. The 12th is a cadent house as are the 3rd, 6th and 9th and planets in these houses are considered weak or afflicted. On the other hand, Moon in the 1st, 4th, 7th, or 10th would be more able to act as these are Angular houses. Planets in Succedent houses of the chart (2nd, 5th, 8th, 11th) are generally considered to be of medium ability to act. Besides Accidental Dignity, there are a range of Accidental Debilities, such as retrogradation, Under the Sun's Beams, Combust, and so forth.
Each sign can be divided into three 10° sectors known as decans or decanates, though these have fallen into disuse. The first decanate is said to be most emphatically of its own nature and is ruled by the sign ruler. The next decanate is sub-ruled by the planet ruling the next sign in the same triplicity. The last decanate is sub-ruled by the next in order in the same triplicity.
While the element and modality of a sign are together sufficient to define it, they can be grouped to indicate their symbolism. The first four signs, Aries, Taurus, Gemini, and Cancer, form the group of personal signs. The next four signs, Leo, Virgo, Libra, and Scorpio form the group of interpersonal signs. The last four signs of the zodiac, Sagittarius, Capricorn, Aquarius, and Pisces, form the group of transpersonal signs.
Dane Rudhyar presented the tropical zodiac primary factors, used in the curriculum of the RASA School of Astrology. The tropical zodiac is the zodiac of seasonal factors as opposed to the sidereal zodiac (constellation factors). The primary seasonal factors are based on the changing ratio of sunlight and darkness across the year. The first factor is whether the chosen time falls in the half of the year when daylight is increasing, or the half of the year when darkness is increasing. The second factor is whether the chosen time falls in the half of the year when there is more daylight than darkness, or the half when there is more darkness than daylight. The third factor is which of the four seasons the chosen time falls in, defined by the first two factors. Thus
In Indian astrology, there are five elements: fire, earth, air, water, and ether. The master of fire is Mars, while Mercury is of earth, Saturn of air, Venus of water, and Jupiter of ether.
A nakshatra (Devanagari, Sanskrit nakshatra, a metaphorical compound of naksha- 'map/chart', and tra- 'guard'), or lunar mansion, is one of the 27 divisions of the sky identified by prominent star(s), as used in Hindu astronomy and astrology (Jyotisha). "Nakshatra" in Sanskrit and Tamil also, thus, refers to stars themselves.
Chinese astrological signs operate on cycles of years, lunar months, and two-hour periods of the day (also known as shichen). A particular feature of the Chinese zodiac is its operation in a 60-year cycle in combination with the Five Phases of Chinese astrology (Wood, Fire, Metal, Water and Earth). Nevertheless, some researches say that there is an obvious relationship between the Chinese 12-year cycle and zodiac constellations: each year of the cycle corresponds to a certain disposal of Jupiter. For example, in the year of Snake Jupiter is in the Sign of Gemini, in the year of Horse Jupiter is in the Sign of Cancer and so on. So the Chinese 12-year calendar is a solar-lunar-jovian calendar.
The following table shows the twelve signs and their attributes.
In Chinese astrology, the zodiac of twelve animal signs represents twelve different types of personality. The zodiac traditionally begins with the sign of the Rat, and there are many stories about the Origins of the Chinese Zodiac which explain why this is so. When the twelve zodiac signs are part of the 60-year calendar in combination with the four elements, they are traditionally called the twelve Earthly Branches. The Chinese zodiac follows the lunisolar Chinese calendar and thus the "changeover" days in a month (when one sign changes to another sign) vary each year. The following are the twelve zodiac signs in order.
The five elements operate together with the twelve animal signs in a 60-year calendar. The five elements appear in the calendar in both their yin and yang forms and are known as the ten Celestial stems. The yin/yang split seen in the Gregorian calendar means years that end in an even number are Yang (representing masculine, active, and light), those that end with an odd number are Yin (representing feminine, passive and darkness), subject to Chinese New Year having passed.