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Could Planet 9 have caused the gap between the heliopause and the Oort cloud?

  1. Jan 24, 2016 #1
    The proposed orbit of Planet Nine looks like it falls in a gap between the heliopause and the Oort cloud; could planet Nine have caused the gap? Would Planet Nine get most of it's energy (electro-magnetic) from extra solar sources, since it is outside the heliopause?
  2. jcsd
  3. Jan 24, 2016 #2
    It's a bit early to be working on the assumption that this planet definitely does exist.
    However if it does, one likely scenario is that it originally formed closer to the the other gas giants, but at some point experienced a gravitational slingshot effect due to a chance alignment of the other planets.
    While travelling outbound it probably would have accumulated a bit more mass, but it's not really likely to have cleaned up the entire zone between the Kuiper belt and Oort cloud.
    One consideration is that the Kuiper belt is more or less in the plane of the solar system, while the Oort cloud is more like a spherical shell.
    Where it's orbit is supposed to be located now is very far from the Sun, but the Sun is still by far the closest star.
    All other stars are so far away that the amount of light the planet would receive from them would not be significantly different to that received by the other solar system planets.
  4. Jan 24, 2016 #3


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  5. Jan 25, 2016 #4
    That's not very helpful mathman, or very informed. The Inner Oort Cloud possibly includes the Sednoids (i.e. objects like Sedna), depending on the model chosen. Planet 9 presumably sculpts the Inner Oort Cloud via its gravity, as its existence is inferred from its effect on the Sednoids.

    Planet 9 is, at a minimum, 200 AU from the Sun. The Kuiper Belt isn't much past 50 AU.

  6. Jan 25, 2016 #5
    The heliopause oscillates depending on the magnetic pressure of the Sun's solar wind and the ram pressure of the interstellar medium. Planet 9's magnetic field might have some influence, but otherwise it's a tiny blip compared to the immensity of the Sun's magnetosphere. Planet 9 still gets far more radiant energy from the Sun than any other form of electromagnetic energy it might encounter out there. Most of its energy would likely come from radioactive decay.
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