Zodiac
A zodiac , also zodiacus (from Latin zodiacus , Greek ζῳδιακός zodiakós ) or German zodiac , is a 20 degree wide zone around the ecliptic , within which the apparent orbits of the sun , moon and planets run. The ecliptic, i.e. the apparent path of the sun, forms the center line. It intersects the thirteen ecliptic constellations.
Until the 19th century and still today in astrology , the zodiac was understood to mean the ecliptic divided into twelve 30 degree sections, the zodiac signs . Because of the precession of the earth's axis , the zodiac constellations are no longer in the zodiac signs of the same name, so the two must be strictly distinguished from one another.
history
The - sidereal - zodiac with its twelve equal 30 ° sections and the beginning with the zodiac sign Aries could have been created by following the schematic ideal calendar with 12 months to 30 days, with the Babylonian year near the spring equinox perhaps from the 7th century BC Began, and was based on the parallel constellations. The complete zodiac with its twelve constellations - still of different lengths - on the ecliptic was finally created in the 5th century BC. Developed or first handed down during the Achaemenid Empire in the area of Mesopotamia. In the 4th century BC The exact division of the zodiac into 12 "signs" at 30 ° as well as the first verifiable mathematical astronomy , which made it possible to calculate the planetary positions based on the coordinate system of 30 ° , arose, probably already in the Seleucid rule after the Hellenistic conquest of the area -Sections of each zodiac. Both developments allowed there another, for the astrology and natal astrology major innovation: the creation of so-called cuneiform "horoscopes", also now available to ordinary people. This means cuneiform tablets which list the planetary positions in the zodiac at birth, occasionally with short sayings about the individual planets or the planetary constellations, the omina.
This twelve-part zodiac along the ecliptic was adopted by the Greeks. In the parapegma of the euctemon , the zodiac, which is still in use today, is found, it is already a tropical zodiac (derived from the Greek τρόποι, trópoi, which means 'turns, turning points'), because here the main points of the sun's orbit (equinoxes and solstices) have the beginning of four set of twelve characters. In this parapegm the names still common today appear; in most cases they are translations of the Babylonian names.
In 1928 the International Astronomical Union (IAU) scientifically determined the boundaries of the sidereal constellations and at the same time postulated 13 constellations along the ecliptic. The thirteenth constellation, the serpent bearer , was ignored in the ancient canonization of the ecliptical constellations, as it is today in astrology, perhaps to enable the twelve-division, which is more attractive in many respects.
The ecliptic constellations
The 13 constellations cut by the ecliptic are the twelve classic zodiac constellations Aries , Taurus , Gemini , Cancer , Leo , Virgo , Libra , Scorpio , Sagittarius , Capricorn , Aquarius and Pisces, as well as the serpent bearer , which lies between Scorpio and Sagittarius and has only been considered since 1928 . The spring equinox is in Pisces today, but it will move 1 ° on the ecliptic in 72 years and will be in Aquarius from around 2200 at the earliest, on closer astronomical observation, however, only from around 2450. The ecliptic as a whole, however, retains its position in relation to of the constellations as far as possible.
| Constellation | symbol | Ecliptical length |
sector | Period of sun passage (approx. 2010) |
|
|---|---|---|---|---|---|
| German | Latin | ||||
| Aries | Aries |
 (U + 2648 ♈ ) |
28.8 ° -53.5 ° | 24.7 ° | Apr 19 - May 14 (25 days) |
| bull | Taurus |
 (U + 2649 ♉ ) |
53.5 ° -90.2 ° | 36.7 ° | May 14th - June 21st (38 days) |
| Twins | Gemini |
 (U + 264A ♊ ) |
90.2 ° -118.1 ° | 27.9 ° | Jun 21 - Jul 20 (29 days) |
| cancer | Cancer |
 (U + 264B ♋ ) |
118.1 ° -138.2 ° | 20.1 ° | Jul 20 - Aug 11 (22 days) |
| lion | Leo |
 (U + 264C ♌ ) |
138.2 ° -173.9 ° | 35.7 ° | 11 Aug - 17 Sep (3 - 7 Days) |
| Virgin | Virgo |
 (U + 264D ♍ ) |
173.9 ° -218.0 ° | 44.1 ° | Sep 17 - Oct 31 (44 days) |
| Libra | Libra |
 (U + 264E ♎ ) |
218.0 ° -241.0 ° | 23.0 ° | Oct 31 - Nov 23 (23 days) |
| Scorpio | Scorpius |
 (U + 264F ♏ ) |
241.0 ° -247.7 ° | 6.7 ° | Nov 23 - Nov 30 (7 days) |
| Snake bearer | Ophiuchus |
 (U + 26CE ⛎ ) |
247.7 ° -266.3 ° | 18.6 ° | Nov 30 - Dec 18 (18 days) |
| Sagittarius | Sagittarius |
 (U + 2650 ♐ ) |
266.3 ° -299.7 ° | 33.4 ° | Dec 18 - Jan 20 (33 days) |
| Capricorn | Capricornus |
 (U + 2651 ♑ ) |
299.7 ° -327.6 ° | 27.9 ° | Jan 20 - Feb 16 (27 days) |
| Aquarius | Aquarius |
 (U + 2652 ♒ ) |
327.6 ° -351.6 ° | 24.0 ° | Feb 16 - Mar 12 (24 days) |
| fishes | Pisces |
 (U + 2653 ♓ ) |
351.6 ° -28.8 ° | 37.2 ° | Mar 12 - Apr 19 (38 days) |
Zodiac as a division of the ecliptic
Since the moon and planets never move far from the ecliptic, it makes sense to describe their location by reference to it. The associated coordinates are ecliptical longitude and latitude . A division of the ecliptic into the twelve equal zodiac signs Aries ♈, Taurus ♉, Gemini ♊, Cancer ♋, Leo ♌, Virgo ♍, Libra ♎, Scorpio ♏, Sagittarius ♐, Capricorn ♑, Aquarius is older than the usual length in degrees today ♒ and fish ♓. These signs are aligned with the main points of spring equinox , summer solstice , autumn equinox and winter solstice, which are each 90 ° apart. The starting point of the length count is the spring or Aries point ♈. The position specification “25 ° 55 ′ ♌, latitude 1 ° 33 ′ n.” Corresponds to the longitude 4 · 30 ° + 25 ° 55 ′ = 145 ° 55 ′.
- See also: The twelve signs of the zodiac with the comparison times of the sun passages through the signs of the zodiac
Individual evidence
- ^ John Herschel : Outlines of Astronomy. Blanchard & Lea, Philadelphia 1857, pp. 200f. ( online )
- ^ Francesca Rochberg : Heavenly Writing . Cambridge University Press, New York, 2004. pp. 129f.
- ↑ James Herschel Holden: A History of Horoscopic Astrology. American Federation of Astrologers, Tempe (USA) 2006. p. 3.
- ↑ Mathieu Ossendrijver: Astronomy and Astrology in Babylonia , in: Joachim Marzahn , Beatrice André-Salvini, Jonathan Taylor, Babylon - Myth and Truth: Catalog for the exhibition in the National Museums in Berlin, Pergamon Museum, June 26, 2008 to October 5, 2008 . Hirmer Verlag, Munich 2008. p. 380.
- ↑ BL van der Waerden: The astronomy of the Greeks. 1988, p. 81. So also later with Hipparchus and Ptolemy . Euctemon's contemporary Meton , on the other hand, stayed with the sidereal zodiac of the Babylonians; here the year points are at 8 ° of the respective signs.
- ↑ BL van der Waerden: The beginnings of astronomy. 1980, pp. 256-259.
- ↑ Jürgen Hamel : Concepts of Astrology . Scientific publishing house Harri Deutsch, Frankfurt am Main 2010. S. 509f., Keyword snake bearer .
- ↑ See the table of dates .
- ↑ See the Aquarian Ages .
- ↑ It only changes when the earth's orbit is disturbed .
- ↑ The example comes from the Astronomia Nova by Johannes Kepler (Chapter 27). It is an observation of Mars from May 7, 1585.
literature
- Wolfgang Hübner : Properties of the signs of the zodiac in antiquity. Their representation and use with special consideration of the Manilus (= Sudhoff's archive . Supplement 22). Steiner, Wiesbaden 1981, ISBN 3-515-03337-8 .
- Robert Powell: History of the Zodiac. Astronova, Tübingen 2007, ISBN 978-3-937077-23-9 (also: Warsaw, Polish Academy of Sciences, dissertation, 2004).
- BL van der Waerden : Awakening Science. Volume 2: The Beginnings of Astronomy. 2nd Edition. Birkhäuser, 1980, ISBN 3-7643-1196-7 .
- BL van der Waerden: The astronomy of the Greeks. Scientific Book Society, 1988, ISBN 3-534-03070-2 .
Web links
- Wiener Zeitung : Christian Pinter: Mythical creatures of the sun path ( Memento from March 10, 2007 in the Internet Archive )
- Photos of the constellations in the zodiac
