A horoscope is an astrological chart or diagram representing the positions of the Sun, Moon, planets, astrological aspects and sensitive angles at the time of an event, such as the moment of a person's birth. The word horoscope is derived from Greek words hõra and scopos meaning "time" and "observer" (horoskopos, pl. horoskopoi, or "marker(s) of the hour"). Other commonly used names for the horoscope in English include natal chart, astrological chart, astro-chart, celestial map, sky-map, star-chart, cosmogram, vitasphere, radical chart, radix, chart wheel or simply chart. It is used as a method of divination regarding events relating to the point in time it represents, and it forms the basis of the horoscopic traditions of astrology.
In common usage, horoscope often refers to an astrologer's interpretation, usually based on a system of solar Sun sign astrology; based strictly on the position of the Sun at the time of birth, or on the calendar significance of an event, as in Chinese astrology. In particular, many newspapers and magazines carry predictive columns, written in prose that may be written more for increasing readership than tied directly to the Sun or other aspects of the solar system, allegedly based on celestial influences in relation to the zodiacal placement of the Sun on the month of birth, cusp (2 days before or after any particular sign, an overlap), or decante (the month divided into 3 ten-day periods) of the person's month of birth, identifying the individual's Sun sign or "star sign" based on the tropical zodiac.
No scientific studies have shown support for the accuracy of horoscopes, and the methods used to make interpretations are pseudo-scientific.:1350 In modern scientific framework no known interaction exists that could be responsible for the transmission of the alleged influence between a person and the position of stars in the sky at the moment of birth. In all tests completed, keeping strict methods to include a control group and proper blinding between experimenters and subjects, horoscopes have shown no effect beyond pure chance. Furthermore, some psychological tests have shown that it is possible to construct personality descriptions and foretelling generic enough to satisfy most members of a large audience simultaneously, referred to as the Forer or Barnum effect.
The horoscope serves as a stylized map of the heavens over a specific location at a particular moment in time. In most applications the perspective is geocentric (heliocentric astrology being one exception). The positions of the actual planets (including Sun and Moon) are placed in the chart, along with those of purely calculated factors such as the lunar nodes, the house cusps including the midheaven and the ascendant, zodiac signs, fixed stars and the lots. Angular relationships between the planets themselves and other points, called aspects, are typically determined. The emphasis and interpretation of these factors varies with tradition.
The Sanskrit term for horo is hora (?). Horo-scope is hora-shastra (?-?). The Latin word horoscopus, ultimately from Greek "nativity, horoscope", literally "observer of the hour [of birth]", from "time, hour" and "observer, watcher". In Middle English texts from the 11th century, the word appears in the Latin form and is anglicized to horoscope in Early Modern English. The noun horoscopy for "casting of horoscopes" has been in use since the 17th century (OED). In Greek, in the sense of "ascendant" and "observation of the ascendant" is in use since Ptolemy (Tetrabiblos 33, 75).
There are four primary angles in the horoscope. These are, in order of power:
The ascendant is the easternmost or sunrise point where the ecliptic and horizon intersect; the ascendant and the midheaven are considered the most important angles in the horoscope by the vast majority of astrologers. In most systems of house division, the ascendant is the cusp of the 1st house and the midheaven is the cusp of the 10th house. The placement of the planetary ruler of the ascendant, called the chart ruler is also considered to be significant. The point in the west diametrically opposing the ascendant is called the descendant, normally the cusp of the 7th house; and the point opposing the M.C. is the cusp of the 4th house, the northernmost point of the chart, called the imum coeli or I.C.
In creating a horoscope the ascendant is traditionally placed at the "nine o'clock" position on the left-hand side of the chart wheel (though traditional rectangular chart formats need not follow this convention). 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 movement provides us with the term rising sign, which is the sign of the zodiac rising over the eastern horizon at the moment of birth. The point on the ecliptic that is furthest above the plane of the horizon at the time is called the Midheaven, or medium coeli (M.C.), placed at the "twelve o'clock position" effectively where the Sun would be if the birth time was midday.
The tropical zodiac defines the vernal point (the first day of spring in the northern hemisphere) as the first degree of Aries, but the sidereal zodiac allows it to precess. Many people are confused regarding the difference between the sidereal zodiac and the tropical zodiac signs. Because of a "wobble" in the Earth's axis of rotation over a period of about 26,000 years (often called a "great year"), the rate at which the vernal equinox precesses in the heavens is approximately 0 deg, 0 min, 50.23 seconds a year, drifting by one degree every 72 years. Precession of the equinoxes thus occurs at a rate of roughly 5 arc minutes of a degree every 6 years. The tropical signs relate to the seasons and not the stars. Here is an example: a person born on, say August 28, 2002 would come to understand that his/her Sun sign was in Virgo according to Western astrology (conventional Sun sign dates August 23, to September 22, of every year), but Sun on that same calendar date of the year 2002 was in the constellation Leo (where it had been since August 10, 2002 and would remain until September 15, when it would then finally cross into Virgo).
It is worth pointing out that the sidereal signs and the tropical signs are both geometrical conventions of 30° each, whereas the zodiacal constellations are pictorial representations of mythological figures projected onto the celestial sphere based on patterns of visible star groupings, none of which occupy precisely 30° of the ecliptic. So constellations and signs are not the same, although for historical reasons they might have the same names.
It is also worth noting that some astrologers don't use the signs of the zodiac at all, focusing more instead on the astrological aspects and other features of the horoscope.
To create a horoscope, an astrologer first has to ascertain the exact time and place of the subject's birth, or the initiation of an event. The local standard time (adjusting for any daylight saving time or war time) is then converted into Greenwich Mean Time or Universal Time at that same instant. The astrologer then has to convert this into the local sidereal time at birth in order to be able to calculate the ascendant and midheaven. The astrologer will next consult a set of tables called an ephemeris, which lists the location of the Sun, Moon and planets for a particular year, date and sidereal time, with respect to the northern hemisphere vernal equinox or the fixed stars (depending on which astrological system is being used). The astrologer then adds or subtracts the difference between the longitude of Greenwich and the longitude of the place in question to determine the true local mean time (LMT) at the place of birth to show where planets would be visible above the horizon at the precise time and place in question. Planets hidden from view beneath the earth are also shown in the horoscope.
The horoscope features 12 sectors around the circle of the ecliptic, starting from the eastern horizon with the ascendant or rising sign. These 12 sectors are called the houses and numerous systems for calculating these divisions exist. Tables of houses have been published since the 19th Century to make this otherwise demanding task easier.
The chart thus begins with a framework of 12 houses. Upon this the signs of the zodiac are superimposed. In the equal house system the cusp between any two houses will fall at the same degree for each of the at 12° of Leo, the second house will begin at 12° of Virgo, the third at 12° Libra, and so on. In house systems that take into consideration the effects of the angle of intersection between the planes of the horizon and the ecliptic, the calculations are more complicated. For these calculations it is essential to know the latitude of the event. Tables are available for these calculations, but they are now commonly calculated by computer. Most astrology computer programs allow the user to choose from a variety of house systems.
Having established the relative positions of the signs in the houses, the astrologer positions the sun, moon, and planets at their proper celestial longitudes. Some astrologers also take note of minor planetary bodies, fixed stars, asteroids (for example, Chiron) and other mathematically calculated points and angles such as the vertex, equatorial ascendant, etc. Many astrologers also use what are commonly referred to as Arabic parts (or Greek Lots), the most common of which is the Part of Fortune (Pars Fortunae).
To complete the horoscope the astrologer will consider the aspects or relative angles between pairs of planets. More exact aspects are considered more important. The difference between the exact aspect and the actual aspect is called the orb. Those generally recognized by the astrological community are Conjunction (0°), Opposition (180°), Square (90°), Trine (120°), Sextile (60°), Semi-Square (45°), Sesquisquare (135°), and Quincunx (150°). Understandably these aspects are more significant when they are exact, but they are considered to function within an orb of influence, the size of which varies according to the importance of each aspect. Thus conjunctions are believed to operate with a larger orb than sextiles. Most modern astrologers use an orb of 8° or less for aspects involving the Sun, Moon, and Jupiter and smaller orbs for the other points. Some astrologers, such as practitioners of Cosmobiology, and Uranian astrology, use minor aspects (15°, 22.5°, 67.5°, 72°, 75°, 105°, 112.5°, 157.5°, 165°) with much narrower orbs.
The major astrological system regarded universally is Vedic Hindu Astrology. As per this, all planets see just opposite i.e. 180 degree aspect. But Mars, Jupiter, and Saturn have special aspects. Mars sees the houses 4th and 8 too from its place in the horoscope, Saturn sees the houses 3 and 10 too from its place, and Jupiter sees 5 and 9 from its place in the horoscope i.e. the house in which they are posited in the lagna chart.
The ascendant (ASC) is a point on the ecliptic that rises on the eastern horizon at sunrise and changes as the earth rotates on its axis. The ascendant is very important in astrological chart interpretation. It exerts more power than the sun, moon and planets because it infiltrates everything in the natal chart. The ascendant is the first point of energy in the natal chart and it represents the way we view life. The sign on the ascendant characterises our expression of "who we are" when dealing with others, and our initial action when dealing with day-to-day concerns.Longitude is necessary in order to determine the position of the Ascendant because horoscopes use local time. Having constructed the horoscope, the astrologer can begin the task of interpreting the chart. This interpretation depends upon which branch of horoscopic astrology is being used......
In Chinese astrology, horoscopes are based on the symbolism of the Chinese zodiac, a system of elements and animals associated with each year according to a Sexagenary cycle. Chinese horoscopes often appear in horoscope sections in newspapers and magazine alongside Western horoscopes.
To optimise the chances of finding even remote relationships between date of birth and individual differences in personality and intelligence we further applied two different strategies. The first one was based on the common chronological concept of time (e.g. month of birth and season of birth). The second strategy was based on the (pseudo-scientific) concept of astrology (e.g. Sun Signs, The Elements, and astrological gender), as discussed in the book Astrology: Science or superstition? by Eysenck and Nias (1982).