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Tropical natal astrology belongs to a long textual tradition that was repeatedly revised. Ptolemy's Tetrabiblos explicitly anchors signs to equinoxes and solstices. Contemporary Western practice combines that zodiac with later planets, competing house systems and several approaches to interpretation; it is not a single unchanged ancient system.
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Western sidereal astrology is a modern Western tradition associated with zodiac calibrations such as Fagan–Bradley. Its defining computational decision is where the twelve equal signs begin relative to a stellar reference. It should not be collapsed into Indian astrology simply because both can use sidereal coordinates.
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Hellenistic astrology is represented by surviving Greek-language authors including Ptolemy and Vettius Valens. Their disagreements matter: a modern reconstruction should identify its textual basis. Current traditional revival practice often emphasizes seven visible planets, sect, sign rulers, lots and time-lord techniques.
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Persian, Arabic-language, medieval Latin and Renaissance astrology form connected but distinct histories. Iranica documents Sasanian engagement with Greek and Indian works and later Arabic and Latin transmission. Scholars translated, combined and revised material; the label 'Arabic astrology' identifies neither one ethnicity nor one complete doctrine.
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Psychological and evolutionary astrology are related modern approaches, not synonyms. Liz Greene's work joins astrology with depth psychology and Jungian interpretation. Jeffrey Wolf Green's school presents a distinct evolutionary paradigm centered on Pluto, the lunar nodes and their rulers, framed as a soul's development.
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Alice Bailey's esoteric astrology belongs to a modern spiritual teaching corpus maintained by Lucis Trust. The seven rays are central to that corpus. This is a particular lineage of esoteric thought, rather than a collective name for all spiritual astrology or a reconstruction of ancient astronomy.
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Modern harmonic astrology is closely associated with John Addey and later authors such as David Hamblin. Hamblin's own account describes both this development and David Cochrane's related vibrational approach. These schools give numbers and aspect families interpretive importance, but do not share a universally standardized meaning for every harmonic.
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Draconic astrology appears in modern practitioner literature associated with writers including Dennis Elwell and Pam Crane. The reviewed exposition by Victor Olliver describes a natal chart rotated so that the north lunar node becomes zero Aries. It is a derived zodiac, not an additional sky observed at birth.
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The Hamburg School grew around Alfred Witte's methods, with Friedrich Sieggrün and Ludwig Rudolph involved in its organization and publishing. Witte-Verlag traces a connected publication to 1925 and the English name 'Uranian' to the following decade. The term names a methodological tradition, not just one organization.
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Cosmobiology is particularly associated with Reinhold Ebertin's publishing and teaching. The Kosmobiologische Akademie's institutional history records earlier uses of the name and Ebertin's subsequent conferences and publications. Its claimed research orientation is part of the movement's identity, not itself evidence that its interpretations have been scientifically established.
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Fixed-star astrology contains multiple methods rather than one extra layer of zodiac degrees. Contemporary work by Bernadette Brady uses parans and stellar phases, while other practitioners compare projected ecliptic longitudes. Historical Behenian star selections belong to a particular transmitted corpus and should not be assumed to equal any modern bright-star list.
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Minor-body astrology expanded as observations and usable ephemerides made more objects accessible. Demetra George's work is an influential practitioner source for Ceres, Pallas, Juno and Vesta and for interpreting asteroid names through myth. Centaurs and dwarf planets add further astronomical populations; those classifications are not interchangeable.
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Heliocentric astrology applies astrological interpretation to a Sun-centered chart. It is a distinct use of astronomical coordinates, not simply another house system. Philip Sedgwick's writings provide one contemporary practitioner framework, including Earth and relationships to planetary orbital features.
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Locational astrology predates its modern computerized maps. Continuum, which preserves Jim Lewis's legacy, credits him with making Astro*Carto*Graphy accessible through computer technology rather than inventing every form of location astrology. Relocation, astrocartography and local-space methods should remain distinguishable.
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Electional astrology selects a proposed starting time for an activity. John Frawley's account describes a traditional Western practice spanning major public beginnings and ordinary activities. Indian muhurta has its own combinations of calendrical and astrological rules. Similar purposes do not make the two rule sets identical.
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Mundane astrology applies celestial symbolism to collective affairs. Ptolemy's second book discusses regional and seasonal questions, including equinoctial and solstitial beginnings. Later traditions developed further event and cycle readings. Financial and medical astrology are specialized applications rather than new planetary calculation systems.
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Modern relationship astrology uses different constructions: synastry retains two charts, a midpoint composite combines their corresponding positions, and a Davison chart calculates an intermediate time and place. Liz Greene's composite reading is one psychological approach, not a universal interpretation of all three methods.