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Question about our solar systems orbital path through the milky way

  1. Sep 9, 2009 #1
    Hello everyone this is my first time posting on this website. I wanted to know if our solar system takes a path through the milky way on a linear plane or if it garbages up and down on an unstable x and y path? Just so you all know I'm not an expert in theories or have any type of degree in astronomy. I have heard alot of things about 2012 end of the world kind of stuff. I dont believe in that kind of thing only hard facts. However I have heard and read about alot of galaxy's having a huge black hole at its center, and gama ray bursts. I figured that if our solar system does rotate through the milky way on an non linear plane then the doomsday scenerio could be plausible. Anyway does any one have the answer. I appolgize for not throughly searching through the forums and blogs but I could'nt find an answer. Thanks
  2. jcsd
  3. Sep 9, 2009 #2
    Do tell why you think that "if our solar system does rotate through the milky way on an non linear plane then the doomsday scenerio could be plausible."

    And yes, stars do oscillate up and down as they orbit the center of the Milky Way, which does harbor a supermassive black hole, that will not kill us all in 2012.
  4. Sep 10, 2009 #3


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    Please put aside fears and concerns about 2012. There is nothing on the galactic or cosmological scale that is going to doom the earth during the next 2 or 3 years, or for a very long time. Locally, that is on the earth, things are more problematic with people running around prophesying a doomsday. I just hope it is not a self-fulfulling prophesy.

    Our solar system is quite distant from the center of the galaxy, and our trajectory in the near term will not take us toward the center.

    Here's an image to put things in perspective.
    http://biocab.org/Cosmic_Cloud-Solar_System-Milky_Way.jpg (no endorsement of the site is implied or intended)
  5. Sep 12, 2009 #4
    Thanks for the information. As far as the doomsday scenerio thing being plausible because of an irregular orbital path, the more I thought about it became very unlikely. I originally thought that if our solar systems path passed over or under the supermassive black hole, than it would be effected by the galactic jets that shoot out from it. Two of my reasons this won't happen. 1 if this was a major problem then I'm sure someone else would have come up with it before I did. 2 our distance from the center is great enough that it wouldnt effect our solar system.
  6. Sep 12, 2009 #5

    D H

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    The latter reason is not correct. If the Milky Way was an active galaxy and if the solar system's orbit around the galaxy took it through one of the galactic jets, then our solar system would be blasted apart. Google "death star galaxy".

    However, while the Milky Way might have been have been active galaxy early in its formation, it isn't one now. There are no galactic jets emanating from the central black hole. Even if it was active, the solar system's orbit would never come close to those jets. The jets emanating from an active galactic nucleus are more-or-less normal to the galactic plane. The solar system's orbit about the galaxy stays fairly close to the galactic plane.
  7. Sep 12, 2009 #6
    Interesting I didn't realize that galactic jets could reach that far. I'll have to read up more about that. Again thanks for the information.
  8. Sep 12, 2009 #7
    There is a science based TV program that discuss this.....I watched it briefly several weeks ago on cable...likely History or National Geographic Channel or similar....

    As I recall the commentator concluded the "doomsday" scenario was rather vague (in my terms, typical media hype and frenzy for ratings analogous to all the hurricanes forecasts each each which typically fail to materialize) .....but late 2012 does have a very unusual alignment of some stars/planets/orbits or somesuch and it was thought this might portend a new conceptual cycle in the heavens....a new beginning....which of course could have been inferred from yesterday's alignments as well....since such things a relative.......It was also mentioned different experts have different ideas just when the Myan calendar actually started so the end might be a year or two off...not very helpful for those trying to whip up a frenzy!!!!

    Meantime, if I recall correctly, isn't our galaxy headed for a collision with the Andromedia galaxy???...but by then our sun will be extinguished and we incinerated as it becomes a red giant engulfing earth in it's plasma....several billion years from now...relax and go buy that big screen TV for football!!!!
  9. Sep 13, 2009 #8


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    It is, but interstellar distances are so great that our sun is highly unlikely to ever collide with any stars in Andromeda.
  10. Oct 11, 2009 #9
    If I could inject some thoughts of mine in the interest of being enlightend, rather than to give others food for fear and spreading more angst:
    Considering we are about to pass through what can commonly be known as the great divide (the area between the north and south divides of the milky way), do we actually KNOW for sure what effects, and what radiation/matter is actually between these poles of the solar system? And what effect will the weakening of our own magnetic field during transition through this area have on our magnetosphere/environment?

    I've also recently heard our sun is actually a binary star, just like many of other stars in our galaxy. This is all a bit biblical and based on the prophecy of wormwood, but I'm not wanting the discussion to actually go there, merely toying with the notion. Many argue that we would have two suns if this were the case, forgetting the fact that a brown dwarf would be almost impossible to pick up or ignorant to the fact that brown dwarfs actually exist. Also just because two companions don't orbit very locally, it doesn't mean they are not binary stars. The orbit could be HUGE, and we would only know of it's existance when it cycles around every say 30,000 years. Then there would be no proof of it's existance in the past other than myth and heresay as no one would remember it. The brown dwarf would have to be MANY times smaller than the sun and be much denser but would have similar gravity etc.

    Some of the planets in our solar system have unusual tilted or even flipped orbits, for which there is absolutely no explanation. Could the massive orbit of a brown dwarf be messing with and causing such irregularities?

    I'd love to hear some sensible responses to this.
    Last edited: Oct 11, 2009
  11. Oct 11, 2009 #10

    Vanadium 50

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    It's difficult to post a sensible response to nonsense, I'm afraid.

    There is no "great divide" that the earth is is about to pass through. Deciding that the sun is is a binary star based on prophesy rather then evidence is unscientific. Extinction events every 30,000 years would be clearly visible in the fossil record, and nothing like this exists: the original Nemesis theory talked about a periodicity of 26 million years. A 30,000 year orbit means that this star is out at about 1000 AU's; that's about Sedna's aphelion. You're talking about an object that is, at minimum, 70 times larger and 5000 times brighter. The objects in our solar system with retrograde orbits are all believed to be captured bodies - hardly a case of no explanation.
  12. Oct 11, 2009 #11
    And there you go. I thought this would happen. There always seems to be one or the other. Science, which still doesn't have all the answers by the way, or pure superstition. You've done nothing to answer the question, but merely pointed out what imperfect science says about imperfect superstition. I am not a scientist I'm glad to say, but science just provides made up words for explainable phenomenon. "retrograde orbits are all believed to be captured bodies" you said it yourself..believed. Is that what your science is about?! Believing. Then in your own words, the bible which many "believe" must be the truth according to your own explanation. ;) 30,000 years was just an example.

    This is the sort of answer I didn't want. Anyone with a better answer? That was infact as non-sensical as the suggestion about 2012 doomsday.
    Last edited: Oct 11, 2009
  13. Oct 11, 2009 #12

    D H

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    First off, what great divide? There is none.

    You are alluding to the Shiva Hypothesis. Material is a bit denser roughly along the galactic plane. The solar system does cross this plane on occasion. However, the solar system is presently about 26,000 light years from from the galactic plane. The last such crossing occurred a few million year ago; the next crossing won't happen for another twenty to thirty million years. Certainly not in 2012.

    Brown dwarfs the mass of the sun don't exist. An object with the mass of the Sun orbiting with a 30,000 year orbit would easily be detecting in terms of perturbations of planetary orbits.

    Here you are alluding to what is called the Nemesis Hypothesis. This hypothesis attributes mass extinction events to a red or brown dwarf much, much smaller than the Sun with an orbital period of 26 million years. Per this hypothesis, the last such event occurred 12-14 million years ago; we are more-or-less perfectly ensconced between such events.

    If either of these hypotheses is correct, and that is a mighty big if, they have nothing to do with a calamity in 2012.
  14. Oct 11, 2009 #13
    Couldn't have put it any better myself :). lol.

    P.S. Jdavisabc you would be well off by reading up a few parts of the bible to do with humility. Learn some respect man.
  15. Oct 11, 2009 #14


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    Science and superstition are by no means on such a similar level, as you imply.

    Nonsense is nonsense and we don't deal in nonsense here. Please reread the forum guidelines.

    Thread locked.
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