#PPOD: This "family portrait" of Uranus' five largest moons was compiled from images sent back on Jan. 20, 1986, by the Voyager 2 spacecraft. In this comparison, we see the relative sizes and relativities of the satellites. From the left, in order of increasing distance from the planet, they are Miranda, Ariel, Umbriel, Titania, and Oberon. Credit: NASA/JPL
The two largest, Oberon and Titania, are about half the size of Earth's Moon, or roughly 1,600 kilometers in diameter. Miranda, the smallest of the five, has about one-quarter to one-third the diameter.