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Plot a point on Earth through the Universe

  1. Feb 1, 2008 #1
    Just a thought...

    Pick a spot/location on the surface of the Earth.

    Now, the Earth is rotating on its axis and also rotating around the Sun (and wobbling a bit too). The sun and our solar system is rotating around our galaxy and our glaxy is moving in the universe as a whole.

    Is there graphical software that could show the path that point on the Earth takes through all this movement? I.e. could you plot exactly where in the universe that particular spot on the Earth was for any date/time...? Bit like a giant spirograph... but without the cogged wheels :)

    Thinking about a sci-fi novel and wormholes/rips in spacetime etc.

  2. jcsd
  3. Feb 1, 2008 #2


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    Relative to what base point? All other stars that you might use are moving also.
  4. Feb 1, 2008 #3

    D H

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    No. The scales differ by too many orders of magnitude.

    Suppose you plotted the Earth's orbit about the Sun on a 1 meter by 1 meter square of paper. That makes one half a meter on this piece of paper equal to 1 AU. On this scale, the Earth is a dot 42 microns in diameter. You can maybe see 25 microns if you peer closely, but then you miss the big picture. You can't really see the Earth's rotation about its axis and the Earth's orbit about the Sun at the same time.

    The Sun is about 26,000 light years from the galactic center. Plotting the solar system's orbit on a 1 square meter sheet of paper means a scale of 52000 light years to one meter. On this scale, the Earth's orbit about the Sun has a diameter of 0.61 nanometers, the diameter of a large atom. The Earth itself becomes a dot a mere 26 femtometers across, the diameter of that large atom's nucleus.
  5. Feb 1, 2008 #4
    Okay thanks, was thinking more along the lines of a 3d viewer that allowed you to zoom in/out on the plot. Just interested in the overall path plotted.
  6. Feb 1, 2008 #5


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    that would only be possible if there was such a thing as absolute space. "plot through the universe" has no meaning. all spatial relationships are relative. without any objects, space has no meaning. so you must choose a reference object and then plot the path of the earth relative to that object.
  7. Feb 1, 2008 #6


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    It wouldn't be as interesting as you'd think.

    As D H points out, the scales differ so greatly that, at any given scale you will see only one - maybe two - factors of movement.

    So, at the scale of the galactic superclusters, it'll look like a simple curved line. Zoom in on that line so much that you're looking at a tiny arc of it so short that it's indistingusihable from straight, and you'll see a tight loop, as the sun goes around the galaxy. Zoom in on that line until only a tiny, tiny arc of the tight loop is visible - so small that it's indistinguishable from a straight line - and you'll start to see the sun's movement through the galaxy. Zoom in a tiny section of that arc until it's just a straight line... etc.

    What you could do if you wanted is compress the scale factors until they are only one order of magnitude apart...

    Nope, that still won't work, your scale still spans 7 or 8 orders of magnitude (micrometers to kilometers). you'd need to compress them until they werre all within 2 orders of magnitude or so.
    Last edited: Feb 1, 2008
  8. Feb 1, 2008 #7
    If you interested in a 2D aproximation (suitably scaled for convenience) of our path relative to say the great attractor, I could possibly create something for you that you can view and zoom in and out of in C.a.R. which is a free geometry software.You would have to do the legwork to find out the velocities and radiuses involved for

    A point at the Equator relative to the axis of the Earth.
    The Earth relative to the Sun.
    The Sun relative to the Galaxy centre.
    The Galaxy relative to the Local Group.
    The Local Group relative to the Super Cluster.
    The Supercluster relative to the Great Attractor.

    The radiuses are required as it is important to calculate the angular velocities to obtain a scaleable path. It will probably be necessary to exagerate the size of the Earth and the Solar system to obtain something that is practical to view. The path would probably resemble one strand of a DNA molecule (A coil that is coiled and coiled again at different scales)
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