The seafloors of Europa and Enceladus may not be prone to fracturing. Such fissures are thought to be important for the prospect of life beneath these moons’ icy shells, so if there isn’t enough stress to cause them, there might also be a shortage of the energy and chemicals that any potential living organisms would need.
We can’t observe the cores of these frigid worlds directly, so we know very little about them. If they fracture often, the fresh …