Moons of Uranus less than half that of Triton (the seventh-largest moon in the Solar System) alone. The largest of the satellites, Titania, has a radius of 788.9 km, or less than half that of the Moon, but slightly more than that of Rhea, the second-largest moon of Saturn, making Titania the eighth-largest moon in the Solar System. Uranus is about 10,000 times more massive than its moons. As of 2016, Uranus is known to have 13 inner moons. Their orbits lie inside that of Miranda. All inner moons are intimately connected to the rings of Uranus, which probably resulted from the fragmentation
Mars trilogy help them better adapt to the new worlds; to breathe thinner air (e.g. Russell), or to see better in the dimmer light of the outer planets. The books also speculate on the colonization of other planets and moons in the Solar System, and include descriptions of settlements or terraforming efforts on Callisto, Mercury, Titania, Miranda and Venus. Toward the end of the last novel, humans are taking sub-light colony ships to other stars, taking advantage of the longevity treatments to survive the trip to their destinations. A great portion of "Blue Mars" is concerned with the effects of extreme longevity