Uranus, the seventh planet from the Sun, is orbited by a diverse group of 27 known moons, ranging from small, irregularly-shaped satellites to larger, more spherical bodies. The Uranian system offers valuable insights into the formation and evolution of celestial bodies, as well as the physical and chemical processes that govern them. This article aims to provide a detailed overview of the most significant Uranian moons, highlighting their unique features and importance in the context of planetary science.
- Titania: The Largest Uranian Moon
Titania, with a diameter of 1,578 km, is the largest moon of Uranus and the eighth-largest moon in the Solar System. Its surface is composed primarily of water ice, with traces of other volatile compounds such as methane and ammonia. Titania exhibits a mix of geological features, including impact craters, chasms, and scarps. The moon is believed to have undergone a period of tectonic activity in its past, which led to the formation of its diverse landscape. The possibility of a subsurface ocean beneath the icy crust has been suggested, although further investigation is needed to confirm this hypothesis.
- Oberon: The Outermost Major Moon
Oberon, the second-largest and outermost of the major Uranian moons, has a diameter of 1,523 km. Like Titania, its surface is composed mostly of water ice, with some rocky material interspersed. Oberon's surface is heavily cratered, indicating an ancient and relatively stable geological history. The presence of large chasms and scarps suggests that Oberon may have experienced tectonic activity in its past, although the moon appears to be geologically inactive today.
- Umbriel: The Dark and Mysterious Moon
Umbriel, the third-largest Uranian moon, has a diameter of 1,169 km. Its most striking feature is its dark and uniformly-coloured surface, which is thought to be due to a layer of radiation-altered water ice and other organic compounds. The moon's surface is heavily cratered and appears to be geologically stable, with no signs of recent tectonic or volcanic activity. The origin of Umbriel's dark surface remains a mystery, with several competing theories proposed.
- Ariel: The Geologically Diverse Moon
Ariel, with a diameter of 1,158 km, is the fourth-largest moon of Uranus. Its surface is composed of water ice, with a mixture of rocky material. Ariel displays a diverse range of geological features, including impact craters, valleys, and ridges. The presence of these features indicates that the moon has experienced significant tectonic and possibly cryovolcanic activity in its past. The exact cause of Ariel's geological diversity remains uncertain, but it is thought to be related to the moon's internal heating and tidal interactions with Uranus.
- Miranda: The Moon with Extreme Terrain
Miranda, the smallest of the major Uranian moons with a diameter of 472 km, is known for its extreme and chaotic terrain. The moon's surface is characterised by a combination of heavily cratered regions, large fault scarps, and high cliffs, some of which are up to 20 km high. The most prominent feature on Miranda is a large, concentric structure called Verona Rupes, which is thought to be