Moons of Uranus geometrical albedo is less than 10%. They are composed of water ice contaminated with a dark material—probably radiation-processed organics. The small inner moons constantly perturb each other. The system is chaotic and apparently unstable. Simulations show that the moons may perturb each other into crossing orbits, which may eventually result in collisions between the moons. Desdemona may collide with either Cressida or Juliet within the next 100 million years. Uranus has five major moons: Miranda, Ariel, Umbriel, Titania, and Oberon. They range in diameter from 472 km for Miranda to 1578 km for Titania. All these moons are relatively dark
Titania (moon) exists, it would have to be far thinner than that of Triton or Pluto. This upper limit is still several times higher than the maximum possible surface pressure of the carbon dioxide, meaning that the measurements place essentially no constraints on parameters of the atmosphere. The peculiar geometry of the Uranian system causes the moons' poles to receive more solar energy than their equatorial regions. Because the vapor pressure of CO is a steep function of temperature, this may lead to the accumulation of carbon dioxide in the low-latitude regions of Titania, where it can stably exist on high albedo