A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a young protostar orbited by a protoplanetary disk. Planets grow in this disk by the gradual accumulation of material driven by gravity, a process called accretion. The Solar System has at least eight planets: the terrestrial planets Mercury, Venus, Earth, and Mars, and the giant planets Jupiter, Saturn, Uranus, and Neptune.
In astronomy, a conjunction occurs when two astronomical objects or spacecraft appear to be close to each other in the sky. This means they have either the same right ascension or the same ecliptic longitude, usually as observed from Earth.
Astronomical symbols are abstract pictorial symbols used to represent astronomical objects, theoretical constructs and observational events in European astronomy. The earliest forms of these symbols appear in Greek papyrus texts of late antiquity. The Byzantine codices in which many Greek papyrus texts were preserved continued and extended the inventory of astronomical symbols. New symbols have been invented to represent many planets and minor planets discovered in the 18th to the 21st centuries.
In Western astrology, astrological signs are the twelve 30-degree sectors that make up Earth's 360-degree orbit around the Sun. The signs enumerate from the first day of spring, known as the First Point of Aries, which is the vernal equinox. The astrological signs are Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius, and Pisces. The Western zodiac originated in Babylonian astrology, and was later influenced by the Hellenistic culture. Each sign was named after a constellation the sun annually moved through while crossing the sky. This observation is emphasized in the simplified and popular sun sign astrology. Over the centuries, Western astrology's zodiacal divisions have shifted out of alignment with the constellations they were named after by axial precession of the Earth while Hindu astrology measurements correct for this shifting. Astrology was developed in Chinese and Tibetan cultures as well but these astrologies are not based upon the zodiac but deal with the whole sky.
Alchemical symbols, originally devised as part of alchemy, were used to denote some elements and some compounds until the 18th century. Although notation was partly standardized, style and symbol varied between alchemists. Lüdy-Tenger published an inventory of 3,695 symbols and variants, and that was not exhaustive, omitting for example many of the symbols used by Isaac Newton. This page therefore lists only the most common symbols.
Astrological belief in correspondences between celestial observations and terrestrial events have influenced various aspects of human history, including world-views, language and many elements of social culture.
The planetary hours are an ancient system in which one of the seven classical planets is given rulership over each day and various parts of the day. Developed in Hellenistic astrology, it has possible roots in older Babylonian astrology, and it is the origin of the names of the days of the week as used in English and numerous other languages.
In astrology, exaltation is one of the five essential dignities of a planet. The exaltation is a place of awareness for the planet, whereas the fall is a position of weakness concerning the function of the planet.
In astrology, a planet's domicile is the zodiacal sign over which it has rulership. This is a separate concept from the houses of the horoscope. A planetary ruler is given to each sign, over which the planet is said to have a more powerful influence when positioned therein. The ruling planet associated with a sign is also used as an implied focus of interpretation for the signs on house cusps in a chart. A planet is considered to be in domal dignity when it is positioned in the sign it rules. This is the strongest of the five essential dignities of a planet. Domicile is an archaic term in infrequent, specialist uses today; most astrologers use the simpler term "sign".
Babylonian astrology was the first known organized system of astrology, arising in the second millennium BC.
Historically, astrological and astronomical symbols have overlapped. Frequently used symbols include signs of the zodiac and classical planets. These originate from medieval Byzantine codices. Their current form is a product of the European Renaissance. Other symbols for astrological aspects are used in various astrological traditions.
A planet symbol or planetary symbol is a graphical symbol used in astrology and astronomy to represent a classical planet or one of the modern planets. The symbols were also used in alchemy to represent the metals associated with the planets, and in calendars for their associated days. Most of the symbols originated in Greco-Roman astronomy; their modern forms developed in the 16th century.
The Thema Mundi was a mythical horoscope used in Hellenistic astrology that shows the supposed positions of the seven visible planets at the beginning of the universe. It purports to exemplify the logic behind the sign rulerships, exaltations, and meanings of the aspects, among other things. The purely symbolic nature of the chart is readily perceived from the impossible positions of Venus and Mercury in it. In the late Middle Ages there has been a confusion between a horoscope of the world and the thema mundi.
In astrology, planets have a meaning different from the astronomical understanding of what a planet is. Before the age of telescopes, the night sky was thought to consist of two similar components: fixed stars, which remained motionless in relation to each other, and moving objects/"wandering stars", which moved relative to the fixed stars over the course of the year(s).
Planetary aspects are interchange of energies at great distances; the respective mass of each planet generates and radiates its own specific energy-field. At times these planetary aspects take a lead over planetary conjunctions. Planetary aspects play an important role in predicting future events. However, there are three great differences between Western astrology and Hindu astrology in computing these aspects - (1) in the former system the count is made from degree to degree, in the latter system the count is made from sign to sign, (2) in the former system the aspect will be mutually the same i.e. if Mars and Jupiter are in trine it can be expressed as either Mars Trine Jupiter or Jupiter Trine Mars, in the latter system if Jupiter is in Aries and Mars in Leo, Jupiter will have full aspect on Mars but Mars will have 50% aspect on Jupiter and, (3) in the former system certain aspects such as sextile are good whereas square and opposition are evil, the latter system does not have such classification in which system aspects by benefic planets and those owning trines i.e. the 5th and the 9th, are always good, and by malefic planets and those owning cadent houses i.e. the 6th, 8th or 12th, are always evil; moreover, the aspect of any planet on its own sign strengthens that house and causes no harm to its indications.
Balarishta in Hindu astrology is one of the Arishtas. These Arishtas are indicated by certain specific planetary situations or combinations or associations present at the time of one's birth or at the time of query or at a particular muhurta or happening as are revealed by the Natal Chart or the Query Chart or the Muhurta Chart. It is a Dosha.
Sanyasa yoga in Hindu astrology are the peculiar planetary situations or combinations seen in certain horoscopes that indicate Sanyasa i.e. renunciation of worldly material life by persons born with those yogas. Sanyasa yogas are also known as Pravrajya yogas.
The following outline is provided as an overview of and topical guide to the Solar System:
The planetae, were the five naked-eye planets known to ancient Greek and Roman astronomers, who assigned them a variety of names, associated them with different gods, and ascribed various qualities to their apparent behaviour in the sky. Some scholars included the Sun and Moon, making seven planets, representing the seven heavenly bodies that moved against the fixed background of stars. This concept survives in astrology, which was not clearly differentiated from astronomy before modern times. Others added the fixed stars, representing a single planet, along with the earth itself, and the antichthon, to make a system of ten.
Astrology in Jewish antiquity is the belief that celestial bodies can influence the affairs of individuals and of entire nations upon the earth. This involves the study of the celestial bodies' respective energies based on recurring patterns that change by the hour, by the week, month, year or by several years. In each of these time categories one of the seven planetary spheres, or what are known as the seven classical planets: the Sun, Venus, Mercury, the Moon, Saturn, Jupiter, or Mars, along with the month's current Zodiac constellation, come into play and influence the sublunary world. At times, it involves a complex combination of several of these factors working together. In Judaism this belief is expressed by the biblical affirmation: "Do you know the laws of heaven / Or impose its authority on earth?" (Job 38:33), from which statement the Sages of Israel have inferred, "There is no single herb below without its corresponding star above, that beats upon it and commands it to grow."
