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“Minor planets”, ranging in size from several
hundred km to boulders (most less than 10 km) |
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104 to 105 objects (with
106 to 107 km average separations) |
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Orbits are fairly circular, most between Mars
and Jupiter; some orbits in resonance with Jupiter; some Earth-crossing |
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“Carbonaceous”: lighter elements (C, Si, Mg),
can be covered with dark organic compounds or rocky material |
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Source: unformed planet or planetesimal |
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“Metallic”: dominantly nickel/iron |
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Source: differentiated body broken up later |
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“Basaltic”: like lava; must have been melted
rock |
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Source: differentiated body or large collision |
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Notes