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Oort cloud dynamics - help needed

  1. Nov 13, 2011 #1
    In writing a science fiction novel, I set it against a backdrop of the Oort cloud and, as part of the plot, I needed to speculate on its origins. Recognising my limitations, I would like some expert feedback on my ideas.

    The first idea I use in my book is that Centaury A & B both developed separately, much like our solar system, until gravity pulled them in to form a binary system. In the process, the Kuiper belts of both star’s were ejected to form the Oort cloud and this was also the origin of the late bombardment in our solar system.

    My second idea is that most of the planets around Centaury A & B were consumed by the stars or ejected into space and our sun captured Neptune, Uranus and Venus. Venus then going on to displace a small planet that collided with earth to form the moon. I figured this might also explain the unusual composition of the ice giants as they could have picked up considerable water from the comets on their journey. It could also explain the large axial tilt of Uranus and the retrograde orbit of Venus.

    My third idea is that the Oort cloud now envelops the Solar system and the Centaury system in an hour-glass shaped cloud that passes through what I call the Waist (as in the waist of an hourglass) centred at the gravitational midpoint, 1.5LY from the sun. I envision slow moving comets becoming trapped at the Waist and accreting to form larger objects before being knocked out by faster moving comets or perturbations from Proxima. In effect, the Waist forms a cosmic cannon that periodically ejects large icy objects that create many of the long period comets and the icy moons of the solar system.

    Do my speculations hold water? Any help would be much appreciated.
  2. jcsd
  3. Nov 13, 2011 #2


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    The Oort cloud is a remnant of the original gas cloud that formed the solar system.
  4. Nov 18, 2011 #3
    Thanks Chronos, I am aware of this but, as far as I know, no one has come up with a mechanism for this to have happened. What I am suggesting is a simpler way for it to have formed, it's the remnants of the Centaury Kuiper belts.

    There are various estimates of the radius of the cloud, many exceeding 1.5LY. What no one seems to consider is that the gravitational mid point between the sun and Alpha centaury is 1.5LY from our sun. This means that any object in the Oort cloud that is orbiting further out than this will be either have been captured by Alpha Centaury or it must be orbiting both stars in a figure of eight orbit and the Oort cloud would have an hourglass shape with a lobe around each star and the waist of the hourglass at the gravitational mid point. Which implies that the cloud could just as easily have originated in the Centaury system as in ours.

    I am not a cosmologist by any means, but i do think there is something in this idea. Can anyone help or point me to where I could get help?
    Last edited: Nov 18, 2011
  5. Nov 18, 2011 #4

    Vanadium 50

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    This is no longer help with a novel, but has become a post on a speculative theory.

    Thread closed.
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