A Quick Estimate of Density
The observation that white dwarfs are
roughly the size of the Earth but contain the mass of the Sun
allows us to make a quick estimate of their densities. The density is the mass divided by the
volume.
Since the volume of the Sun is about
a million times larger than that of the Earth (and thus of a white dwarf),
the average density of a white dwarf
is a million times larger than that of the Sun. This estimate is
approximately
correct: white dwarfs have densities that are typically about a million grams per cubic
centimeter while the Sun has a density a little more than one gram per cubic centimeter.