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Elements on earth

  1. Apr 19, 2012 #1
    If super nova is responsible for all elements on earth, including the ones that humans were made from, why aren't all elements found on every planet?
  2. jcsd
  3. Apr 19, 2012 #2
  4. Apr 19, 2012 #3


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    I'd be willing to bet that all natural stable elements and the longer lived unstable ones are found on every planet in at least trace amounts. The differences in the formation of each planet ultimately decides the ratio of one element to another.
  5. Apr 20, 2012 #4
    Within 4AU distance from the Sun, temperature was too high favoring only high melting point materials (iron, silica etc) to gather together to form rocky planets. This matter is rare (i.e. just 1% of total matter) and thus the terrestrial planets could not grow bigger. Further away, lower temperature created ices that gathered together to attract huge quantity of Hydrogen and Helium to become gas giants.
  6. Apr 20, 2012 #5


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    Still, I'm sure Drakkith is right, and all elements are found on every planet, just in different concentrations. To the OP - can you name a stable element not found on Earth?
  7. Apr 20, 2012 #6


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    This is a nice theory which can explain the position of the planets in our solar system. However, it is known that there are a lot of other planet distributions in other systems - including gas giants very close to the star.
    While it might be true that these gas giants cannot form too close to the planet, they can change their orbit a lot after their formation.

    Same here.
  8. Apr 20, 2012 #7
    One can test this hypothesis by looking at the element abundances in extraterrestrial materials that we already have: Moon rocks and meteorites. Some meteorites come from various sizable objects, like the Moon, Mars, and asteroids like Vesta.

    You'll have to search through the literature to find detailed numbers, but from what I've found, many of the stable elements are present.

    For the Sun, one can look for elements in its spectrum, and to date, about 60 have been found. That's much more difficult for other stars, however.
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