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Dark Rift

  1. Oct 17, 2012 #1


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    Here,you can find an explanation about Dark Rift.
    But There are questions which are not answered here,nor somewhere I could find
    Is Dark Rift a cloud which is rotating around the galactic center or its more like a dust belt surrounding it?
    Also at the end of this page,
    I can't understand how can this happen.
    Could somebody explain?
  2. jcsd
  3. Oct 17, 2012 #2
    It's kind of silly. The Earth orbits the Sun. At about winter solstice a line drawn from the Earth through the center of the Sun would point at the dark rift.

    Lame. Very lame.

    Everything in the galaxy orbits the center, so that includes the Dark Rift clouds.
  4. Oct 17, 2012 #3


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    So Dark Rift is a collection of dust clouds orbiting the center and some times,solar system,which is also orbiting,passes through them?But how can that be once a year and so regularly?
  5. Oct 17, 2012 #4
    no it just "looks like" the sun passes in front of the Dark Rift

    the "sky" can be likened to a big sphere called the Celestial Sphere. Since most objects in the sky (stars, dust clouds, galaxies) are so far away, the movement of the Earth doesn't cause any appreciable change in their position in the sky.

    It's like when you're driving down the highway and you look off into the distance. You can see objects very far away and you can see the grass right on the side oft he road. The stuff that is really far away appears to move much more slowly than the grass on the side of the road. Now, the stuff that's fara away in this case is just like a few miles away or something, where the stars in the night sky are many many light years away.

    As the Earth goes around the sun in a circle, we just don't notice the apparent change in position of these objects because the change is too tiny for us to notice with just our eyes.

    So if you can picture the sun with the Earth making a circle it, try and picture the rest of the objects in the night sky around it. If you draw a line from the Sun to the Earth, and keep going with it, the line will point to a spot on the celestial sphere. The line will move across the celestial sphere as the Earth orbits the sun. At some point, the line will point at the Dark Rift, and from our perspective, the Sun would appear in front of the Dark Rift.


    the image should help you get an idea of what you should be picturing
  6. Oct 17, 2012 #5


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    Thanks both
    And yeah SHISHKABOB,that's what I thought but the article in NASA explained it somehow that I hesitated to think maybe solar system really passes through the Dark Rift,its not explained clearly.
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