If Jules Verne knew about Saturn’s core, he would have written a book about sailing to the center of the ringed planet. It tursn out Saturn’s core is a hidden internal ocean that moves as the plant turns. Here’s more from Astronomy Now:

Subtle ripples in Saturn’s innermost rings indicate the planet’s core is not a compact, solid structure as some have theorised but more like a thick “soup” of ice, rock and metallic fluids extending across 60 percent of the planet’s diameter.

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“We used Saturn’s rings like a giant seismograph to measure oscillations inside the planet,” said Jim Fuller, assistant professor of theoretical astrophysics at Caltech and co-author of a paper in Nature Astronomy. “This is the first time we’ve been able to seismically probe the structure of a gas giant planet, and the results were pretty surprising.”

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