Uranus possesses at least one horseshoe orbiter occupy

Many argue that the differences between the ice giants and the gas giants extend to their formation.[111][112] The Solar System is believed to have formed from a giant rotating ball of gas and dust known as the presolar nebula. Much of the nebula's gas, primarily hydrogen and helium, formed the Sun, while the dust grains collected together to form the first protoplanets. As the planets grew, some of them eventually accreted enough matter for their gravity to hold onto the nebula's leftover gas.[111][112] The more gas they held onto, the larger they became; the larger they became, the more gas they held onto until a critical point was reached, and their size began to increase exponentially. The ice giants, with only a few Earth masses of nebular gas, never reached that critical point.[111][112][113] Recent simulations of planetary migration have suggested that both ice giants formed closer to the Sun than their present positions, and moved outwards after formation, a hypothesis which is detailed in the Nice model
Uranus has 27 known natural satellites.[113] The names for these satellites are chosen from characters from the works of Shakespeare and Alexander Pope.[57][114] The five main satellites are Miranda, Ariel, Umbriel, Titania and Oberon.[57] The Uranian satellite system is the least massive among the gas giants; indeed, the combined mass of the five major satellites would be less than half that of Triton alone.[9] The largest of the satellites, Titania, has a radius of only 788.9 km, or less than half that of the Moon, but slightly more than Rhea, the second largest moon of Saturn, making Titania the eighth largest moon in the Solar System. The moons have relatively low albedos; ranging from 0.20 for Umbriel to 0.35 for Ariel (in green light).[16] The moons are ice–rock conglomerates composed of roughly fifty percent ice and fifty percent rock. The ice may include ammonia and carbon dioxide.[83][115]

Among the satellites, Ariel appears to have the youngest surface with the fewest impact craters, while Umbriel's appears oldest.[16][83] Miranda possesses fault canyons 20 kilometers deep, terraced layers, and a chaotic variation in surface ages and features.[16] Miranda's past geologic activity is believed to have been driven by tidal heating at a time when its orbit was more eccentric than currently, probably as a result of a formerly present 3:1 orbital resonance with Umbriel.[116] Extensional processes associated with upwelling diapirs are the likely origin of the moon's 'racetrack'-like coronae.[117][118] Similarly, Ariel is believed to have once been held in a 4:1 resonance with Titania.[119]

Uranus possesses at least one horseshoe orbiter occupying the Sun–Uranus L3 Lagrangian point – a gravitationally unstable region at 180º in its orbit, 83982 Crantor.[120][121] Crantor currently moves inside Uranus's co-orbital region on a complex, temporary horseshoe orbit. 2010 EU65 is also a promising Uranus horseshoe librator candidate