Four of Uranus's Moons Might Contain Briny Oceans

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https://skyandtelescope.org/astronomy-news/four-of-uranuss-moons-might-contain-briny-oceans/

By Emily Lakdawala, Sky & Telescope. 

Excerpt: A new paper re-analyzing Voyager observations suggests that four of Uranus’ five icy satellites also host oceans: Ariel, Umbriel, Titania, and Oberon. (Only small Miranda, intermediate in size between Saturn’s Mimas and Enceladus, appears not to.) The oceans are desperately thin: less than 30 kilometers (20 miles) thick inside Ariel and Umbriel (both of which are about 1,000 kilometers across, similar in size to Saturn’s Tethys and Dione), and less than 50 kilometers thick within Titania and Oberon (which are larger at about 1,500 kilometers, similar to Saturn’s Rhea and Iapetus). If the oceans exist, they would be left over from much larger liquid layers that formed when the moons first formed. ...They’d be extremely briny, hyper-concentrated with whatever dissolved materials helped to lower the temperature at which water would otherwise freeze. There are two candidate materials: salt and ammonia.... 

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