|Astronomers have calculated the diameters of various types of planets
given certain compositions and masses. This image shows the relative
sizes of six different kinds of planets with different compositions, and
depending on whether they have the same mass as Earth, or five times the
mass of Earth. Note that the 5-Earth-mass planets are larger than their
1-Earth-mass counterparts, but they are not five times larger due to the
gravitational compression that occurs when a planet's mass is increased.
The planets are shown silhouetted against the Sun, as if they are
transiting planets seen from afar.
Credit: Marc Kuchner/NASA GSFC.