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Astrology: Thirteenth Constellation

  1. Apr 26, 2003 #1
    I wondered if anyone had specific information about the thirteenth constellation of ancient astrology.

    Now there are 12 constellations to work with in astrology.

    Where did the thirteenth go?
    Where did it come from?

    What little information I have about it has it connected to the Druids and trees or something.
  2. jcsd
  3. Apr 26, 2003 #2


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    the 13th constellation is ophiuchus, the sign of the bear located in the heavens between scorpio and sagittarius...it has no relation to astrology because astrology is based on 360 degrees (a perfect circle) / 12 sections of the earth's ecliptic...
  4. Apr 26, 2003 #3

    Thanks Kerrie. Is that the constellation Ursus or Ursus minor or something? Is it a Russian configuration?

    Yes, 360 degrees. The Feng Shui compass and Feng Shui's purpose to arrange things in such a manner that the arrangement benefits the whole also utilizes the Chinese form of astrology. I mean, Feng Shui and Astrology are both primarily about the effects of placement and arrangement. Chinese astrology uses twelve animals... each representing a 12 unit, 360 some-odd day year or the 360 degrees in a cycle. This form of astrology may have a bear represented in it. It has snakes, dragons, horses, monkees... etc...

    I also remember hearing that they had 13 "houses" or constellations at one point. I can be mistaken, as well... I'll ask around.

    Thanks again!
    Last edited: Apr 26, 2003
  5. Apr 27, 2003 #4


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    The constellation Ophiuchius depicts a snake, not a bear.
  6. Apr 27, 2003 #5


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    i stand corrected...it is a serpent!
  7. Apr 27, 2003 #6
    Nothing to do with Ursus?

    I got the chinese astrology wrong. Its a 12 year cycle, like regular astrology... but there is a 13th constellation there as well that no longer exists. I have source to tell me about it but not at this time.
  8. Apr 29, 2003 #7


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    Constellations are secondary to houses. The main point is that the old systems are not based in decimal numbers, so the most useful division sytem is by 12, which contains a lot of simple factors. It should be really really stupid to use a prime number, say 11 or 13, to divide the circle. A most interesting historical question could be why there are 12 houses instead of 16, 8 or 4. It is clear you want a multiple of 4 because you want to mimic the cardinal points.

    Now, one you have 12 houses, you look for stars or constellations nearby, and you get the names. That is all.

    Note that we have 360 degrees in a circle just because of the same reasons. Can you imagine to divide the circle in 390 degrees?
  9. Apr 29, 2003 #8
    Thanks Arivero. This totally lines up with a question I had on the old PF Version 2... It had to do with the origin of the compass. As I looked through the information I found the division of 360 degrees to go back quite aways... at least to 9000 years ago with the Feng Shui compass... it was a simple magnetized lode stone floating on water in the middle of some incredibly detailed interpretations of the degrees. The inscriptions look like old computer cards with the linear hole punches.

    I'm still waiting to hear back about the 13th constellation or house... not sure which it is. It has other implications that have nothing to do with astrology... for me.

    I will mention here, mind you... Feng Shui and Astrology are related in their study of placement and the effects of placement and arrangement... and how it effects, in various degrees, energy or "chi".
  10. Apr 30, 2003 #9


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    I think you are refering to Ursa Major and Ursa Minor, The big and little bears. They are more commonly known as the big and little dipper. Neither of these constellations are anywhere near the ecliptic, and the ecliptic has to pass through a constellation for it to be a member of the Zodiac.
  11. May 2, 2003 #10
    Thanks Janus. I'm just a klutz when it comes to this stuff... etc...

    I'd still like to know how the Chinese arrived at their rendition of Astrology. The Wood Goat, Rat, Snake, Dragon... all those animals... did they see the "ecliptic constellations" differently from the Egyptians or gypsies or whoever it was that originated the western version?
  12. May 18, 2003 #11


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    Like Janus said, the zodiacal constellations are those that cross the ecliptic (imaginary line across the sky projected from the Earth's equator).

    We all know the standard 12 constellations that make up the zodiac. But technically, based on the current drawings of the constellation's boundaries, Ophiuchus also crosses the ecliptic. Ophiuchus is not used in astrology as far as I know.

    But keep in mind that constellations are just our connecting-of-the-dots in our imaginations. The stars in each constellation usually don't have any relation to each other (except for being somewhat nearby to us in the Milky Way galaxy). The "boundaries" of the constellations are even broader areas drawn around those pictures of bears and warriors and microscopes that we imagine. The sky is divvied up into 88 constellations. 13 cross the ecliptic. The sun and planets "enter" (appear in the foreground of) even more constellations than that.

    Oh, and Ophiucus is the Serpent Bearer.
    Last edited by a moderator: Apr 20, 2017
  13. May 20, 2003 #12


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    thanks for the clarification, it is difficult to find any information in astrology regarding the constellation opiucus because constellations actually have NOTHING to do with astrology except to just give a name for common understanding...:wink:
  14. May 20, 2003 #13
    Yes, I'd like to second the thank you for everyone's input on this.

    It is clearer where the idea of a 13th constellation comes from for me.

    Yes, Kerrie, the constellations simply provide a reference point for an astrologer. Thank you! I am told that a certain book store has an ancient book that pertains to the Physics of Astrology. When I finally get to it... (in Constantinoples)... I'll try to read it and decifer it and report back to this location.

    The Physics of Astrology is the next thread and I'll put it up now. Mind you... I'll have nothing to say about it... just hoping someone has some of that sort of information on it... you know... the quantum/chaos/string/relativity aspect of the physical universe and its dynamic effect on the living organism we all lovingly refer to as humans!!!
    Last edited: May 20, 2003
  15. Nov 12, 2009 #14
    Hey all, this is my first post.

    There is in fact a 13th constellation, but it has originated from the Greeks, not the Babylonian cultural sphere that depicts the 12 constellation signs in the zodiac. This constellation is recognized in the sidereal zodiac.

    I am not ignoring that the Babylonian cultural sphere has 360 degrees, and I agree that dividing that using a prime number such as 13 would be pointless.

    Instead of viewing a calendar year as 12 months, try taking another approach. A year consists of 365 days, but every fourth year is a leap year, therefore having 366 days. Divide this by 13, and you come to an answer of 28.153864 (etc), or 28 days. Or, try dividing 366 days by 28 days, and you come to an answer of 13.07142857 (etc), or 13 constellations.

    Need more proof? Try http://en.wikipedia.org/wiki/Ophiuchus[/B] [Broken] and take the coordinates that are given that show the star clusters that are found in Ophiuchus (I used IC 4665) and enter them into the search field in Google Earth. By typing in the coordinates, it brings you directly to the constellation of Ophiuchus. It is in fact at the center of the celestial equator.

    Thanks for your time :)


    (references: http://en.wikipedia.org/wiki/Ophiuchus; [Broken] Google Earth)
    Last edited by a moderator: May 4, 2017
  16. Nov 12, 2009 #15
    In North America. In the UK the man-in-the-street wouldn't know what you were talking about, but he would probably be familiar with the plow.
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