Home > List of solar system objects by radius

In the case of the Sun, Jupiter, and Saturn, the volumetric mean radius is used. For mostly spherical objects ( oblate) such as planets and large planetoids, the equatorial radius is used. For irregular objects, the radii along three axes are given.

The ordering is not the same as the order of a list of solar system objects by mass because some objects are denser than others. For instance Uranus is bigger than Neptune but less massive, and although Ganymede and Titan are larger than Mercury, they have less than half its mass.

The list is incomplete because the radii of many asteroids are not accurately known, or even well-defined in the case of irregular objects.

The rankings of some remaining natural satellites are shown below. There are various asteroids larger than many of these, but the exact sizes of many asteroids are not known precisely enough although asteroid diameters can sometimes be determined by timing stellar occultations. In any case many asteroids are known to be highly irregular in shape—some are not even approximately spherical—making any comparison of radii infeasible even if exact figures are known.