Instead of having a hard sphere of rocks and metals, as some theories had suggested, the core appears to be a sloppy mixture of ice, rocks, and metallic fluids. This is usually referred to as a fuzzy, or diffuse core, without clearly defined boundaries. The findings suggest that the core extends to about 60 percent of the planet’s radius, much larger than previously thought. This puts it at around 55 times as massive as Earth and containing enough ice and rocks to make 17 Earths.
“We used Saturn’s rings like a giant seismograph to measure oscillations inside the planet,” co-author Assistant Professor Jim Fuller from Caltech said in a statement. “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.”
“The fuzzy cores are like a sludge,” added lead author Dr Christopher Mankovich, also from CalTech. “The hydrogen and helium gas in the planet gradually mix with more and more ice and rock as you move toward the planet’s center. It’s a bit like parts of Earth’s oceans where the saltiness increases as you get to deeper and deeper levels, creating a stable configuration.”
The rings of Saturn are a collection of fine dust and ice organized into large bands with gaps within them. They are susceptible to many perturbations and the idea that they could be used to probe the interior of the planet has been around for the last three decades. Like earthquakes on our planet, oscillations in Saturn’s interior can make the planet jiggle around ever so slightly. Those motions, in turn, cause ripples in Saturn’s rings.
Jesus: Hey, Dad? God: Yes, Son? Jesus: Western civilization followed me home. Can I keep it? God: Certainly not! And put it down this minute--you don't know where it's been! Tom Robbins in Another Roadside Attraction