In a new study published in the journal Nature Astronomy, two astronomers at the California Institute of Technology analyzed these oscillating rings to reveal new information about Saturn’s core. For their research, they used older data from NASA’s Cassini spacecraft, which orbited the ringed giant for 13 years before it plunged into the planet’s atmosphere and disintegrated in 2017.
The findings suggest that the planet’s core is not a solid rock ball, as some previous theories have suggested, but a diffuse soup of ice, rocks and metallic liquids – or what scientists call a “fuzzy” core. The analysis also shows that the core extends over 60% of the planet’s diameter, making it significantly larger than previously thought.
“We used the rings of Saturn as a giant seismograph to measure vibrations within the planet. This is the first time we’ve been able to seismically study the structure of a gas giant planet, and the results were pretty unexpected, ”says co-author Jim Fuller, assistant professor of theoretical astrophysics at California Institute of Technology.
“Detailed analysis of Saturn’s oscillating rings is a very elegant form of seismology that allows you to infer the characteristics of Saturn’s core,” says Jennifer Jackson, William E. Leonhard professor of mineral physics at the Seismological Laboratory at the California Institute of Technology.
The lead author of the study is Christopher Mankovich, a planetary research scientist working for Fuller’s group.
The findings are the best evidence for Saturn’s fuzzy core and are consistent with recent data from NASA’s Juno mission, which suggests that the gas giant Jupiter may also have a similar diluted core.
“The hydrogen and helium gases on the planet are gradually mixing with more and more ice and rocks as you get closer to the center of the planet. It’s a bit like parts of the Earth’s oceans where salinity increases as you go deeper and deeper, creating a stable configuration, ”explains Mankovich.
The idea that Saturn’s wobbles can create waves in its rings and that the rings can thus be used as a seismograph to study the interior of Saturn was first pioneered in research in the early 1990s by Mark Marley (BS ’84) and Caroline Porco (PhD ’83.), Who later became the head of the Cassini imaging team.
The first observation of this phenomenon was made by Matt Hedman and P.D. Nicholson (Ph.D. ’79) in 2013, who analyzed the data obtained by Cassini. Astronomers have found that Saturn’s C-ring contains several spiral patterns caused by fluctuations in Saturn’s gravitational field, and that these patterns are different from other waves in the rings caused by gravitational interactions with the planet’s moons.
Now Mankovich and Fuller have analyzed the structure of the waves in the rings to build new models of the interior of Saturn.
“Saturn always trembles, but imperceptibly. The planet’s surface moves about a meter every 1-2 hours, like a slowly wobbling lake. Like a seismograph, the rings pick up gravitational disturbances, and the particles in the ring begin to swing, ”says Mankovich.
The researchers say the observed gravitational ripples indicate that the deep interior of Saturn, while fluctuating as a whole, is composed of stable layers that formed after heavier materials descended towards the middle of the planet and stopped mixing with lighter materials above them. …
“For the planet’s gravitational field to oscillate at these specific frequencies, the interior must be stable, and this is only possible if the proportion of ice and rock gradually increases as you get closer to the center of the planet,” Fuller says.
Their results also show that the core of Saturn is 55 times more massive than the entire Earth, of which 17 Earth masses are ice and rock, and the rest is a liquid of hydrogen and helium.
Hedman, who is not involved in the current study, says: “Christopher and Jim were able to show that one ring feature is compelling evidence that Saturn’s core is extremely fuzzy. I look forward to thinking about what all the other elements of the ring created by Saturn can tell us about this planet. “
In addition, the findings challenge existing models for the formation of gas giants, according to which first rocky cores are formed, and then large shells of gas are attracted. If the planetary cores are indeed fuzzy, as the study suggests, the planets may instead include gas earlier in the process.
Earlier Cursor wrote that unusual substances discovered on the moon of Saturn… An international team of astronomers have found an unusual feature in the spectrum of light reflected from Saturn’s icy moon Rhea.
Besides, scientists said that the moon of Saturn may be suitable for life… The crater on the moon of Saturn, Titan, turned out to be a suitable place for the origin of life.
The cursor was reporting that Scientists have solved the main riddle of Saturn.
Recall that scientists told which stars can produce gold and platinum.
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