General Properties








• Radius: 7 x 10⁸m
          700 thousand km, ~100 Earth Radii
  

  
  

• Mass: 2 x 10³⁰ kg
          300,000 Earth Masses
  

  
  

• Density: 1 g/cm³
      Equal to Water. Earth average is 5.5 times more dense
      Varies greatly with radius: 150 g/cm³ at core!
  

  
  

• Temperature: 5780 K (Kelvin Degrees) at Surface
      Also varies greatly with radius: 15 million K at core!
  

  
  

• Composition (by Mass):	71%	Hydrogen
  	27%	Helium
  	2%	Other (C, N, O, Mg, Si, Fe, etc)

  
  

  
  

      How do we know this??????