A second Nature study suggests that Enceladus's orbit, and corresponding tides on Saturn, could make the geyser eruptions regular and predictable.
Though the ice-friction theory could strike a blow to hopes for liquid water near the moon's surface, the theory still proposes that liquid water exist somewhere inside Enceladus.
"We suggest that you need to have an ocean somewhere down there," Nimmo explained.
"If you didn't, the ice shell would be stuck to the rigid rock interior [and would not move]. If there is an ocean below and the ice shell is floating, it could move to produce the friction and heating."
Amy Simon-Miller, an astrophysicist at NASA's Goddard Space Flight Center in Maryland, says it may be some time before Enceladus's true nature is known.
"The details of the internal structure may or may not be discernable from these predictions," she cautioned, "because Cassini is just not optimized for studying Enceladus.
"We probably won't get a good sense of the interior until we can send [a] dedicated mission."
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