New modeling suggests that four of Uranus’ largest moons—Ariel, Umbriel, Titania, and Oberon—likely harbor subsurface oceans between their icy crusts and rocky cores. This conclusion arises from a combination of re-analysis of Voyager data and new computer simulations. These moons, previously thought to lack the necessary internal heat to sustain liquid water, may actually maintain ocean warmth due to heat generated in their rocky mantles and the presence of antifreeze substances like ammonia and salts. Although Titania, the largest moon, was previously considered the most likely candidate to retain internal heat, the modeling indicates that smaller moons could also possess similar conditions.
The study published in the Journal of Geophysical Research: Planets provides insights into the interiors of the five large moons and highlights potential geological activity, as evidenced by observed surface features, particularly on Ariel. While Miranda may have had subsurface water in the past, it appears too small to maintain heat and is likely frozen now. The findings prompt further research into the moons’ composition and structure, which could inform future missions to investigate these ocean worlds more comprehensively.
