Not Rocky but Fuzzy Core: Cassini Imaging, Recent Research Claim Saturn as a Giant Soupy Planet

Data from the ill-fated Cassini probe said that Saturn's core is not the dense rock mass that scientists initially thought, but rather a soupy muck. Though NASA's probe may have died when it plummeted into Saturn's atmosphere in 2017, information on the way the gas giant's rings wobble has revealed surprising insights about what is deep beneath.

Although Saturn is a gas giant, the magnitude of the forces at work at the planet's core has led to speculation that it is made of rock. After all, crushing forces were supposed to have cemented the core due to the gravitational pressures exerted on the minerals there.

The Cassini data, on the other hand, does not necessarily support that notion. While the spacecraft was damaged long before anything reached Saturn's core, Caltech scientists might develop a fresh theory based on measurements of the planet's distinctive rings. They were able to deduce what was going on within Saturn by looking at the jiggling of the rings.

Researchers reported the data of the study, titled "A Diffuse Core in Saturn Revealed by Ring Seismology," in the journal Nature Astronomy.

Saturn's Core Bigger Than Previously Believed

Jim Fuller, Caltech's theoretical astrophysics assistant professor and study co-author, said in a statement that they exploited Saturn's rings like a gigantic seismograph to monitor internal oscillations. He said that it is the first time that they were able to seismically investigate the structure of a gas giant planet. According to Fuller, results were somewhat "unexpected."

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CNN said that the core of Saturn looks bigger than previously thought, far from having a tiny, dense core of rock. It might, in fact, span 60% of the planet's diameter and not that hard. Instead, it is a "fuzzy" core, which is described as "a dispersed soup of ice, rock, and metallic fluids."

Unsurprisingly, sludge is not any more inviting than rock. It is estimated that around 17 Earth-masses of the core are ice and rock, with the rest 38 Earth-masses being fluid hydrogen and helium. According to the astronomers, it is also not a homogeneous mix. In the same CNN report, they believed that that distinct, stable layers have developed based on the weight of each component.

Fuzzy Planets

The findings also align with other recent observations from our planetary neighbors. Knowable Magazine cited NASA's Juno mission findings that Jupiter's core may likewise be fuzzy. If this is confirmed, it might mean that gas giants do not develop in the often assumed way.

That theory proposed that a rocky core formed first, and then gases accumulated around it, increasing gravity and the planet's size over time. With a fuzzy core, the gas buildup would have to start much sooner.

Christopher Mankovich, the study's principal author and a Caltech postdoctoral scholar research associate, noted Saturn's subtle shaking in a SciTechDaily report. He said that the planet's surface is like a gently rippling lake that moves approximately a meter every one to two hours. The rings pick up gravity disturbances like a seismograph, and the ring particles begin to jitter around.

Though the forthcoming James Webb Space Telescope has the planet, and its moon, Titan, on its agenda, NASA has yet to designate a replacement mission to Cassini.