Body        Mass (kg)      Radius (m)       Avg. Density (kg/m^3)
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  Mercury     3.3 x 10^23     2.44 x 10^6          5423

  Earth       6.0 x 10^24     6.38 x 10^6          5516

  Mars        6.4 x 10^23     3.40 x 10^6          3887

  Moon        7.4 x 10^22     1.74 x 10^6          3353

  Comet 67P   1.0 x 10^13     1.64 x 10^3           541

  Jupiter     1.9 x 10^27     7.15 x 10^7          1241

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