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Solar system space dust avg density[kg/m^3]

  1. Sep 25, 2012 #1
    What avg density [kg/m^3] may I attribute to solar system space dust? Halliday & Resnick give
    E-18 to E-21 [kg/^3]. This will allow me to compute solar system density, if I know solar system radius[m], ie, distance from edge of solar system to centre-of-mass of our Sun.
    By 'space dust' I mean any mass, not found within our Sun and its planets. This would include
    moons, comets, asteroids. If you can give me the total mass and volume of the moons in our solar system, then I will alter my definition of space dust to mean any mass, not found within our Sun, moons, and suns planets.
  2. jcsd
  3. Sep 26, 2012 #2
    There are so many moons in the solar system. Make an approximation. Wikipedia has the masses of every moon in our solar system. Find out how many ones there are of significant size and make an order or magnitude calculation. I don't know how much it will change the numbers, the solar system is pretty huge...Also, what do you define as the edge of the solar system?
  4. Sep 26, 2012 #3


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    A good first approximation for the total mass of the solar system is the mass of the sun.
    Include the planets, and you get an even better approximation.
    If you really care about the 6. or 7. digit, add the big moons (there are less than 10 with relevant mass) and look for some estimates about Kuiper belt objects - problably the biggest source of uncertainty.
  5. Sep 26, 2012 #4


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    The sun comprises over 99% of the mass of the solar system.
  6. Sep 27, 2012 #5
    mfb, chronos, I think the OP wanted to leave out the sun and the planets in his calculations...But yes, you're right, the density of the solar system in its entirety is basically determined by the sun.
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