The Mystery Of Saturn's Ravioli-Shaped Moons Has Finally Been Solved


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(Credit: NASA/JPL-Caltech/Space )

After almost twenty years in space — thirteen of which were spent making extraordinary discoveries about the Saturn system, including its rings and natural satellites — NASA's Cassini spacecraft finally ran out of fuel. However, shortly before plunging into Saturn's atmosphere on September 15, 2017, the probe completed one final important mission: six close flybys of tiny moons located inside, or near, Saturn's rings.

While all of Saturn's 62 moons are intriguing, researchers were particularly curious about six small, odd-shaped satellites that are nestled against the edge of its rings and sport different colors. Fortunately, Cassini was able to collect detailed data on five of them — Daphnis, Pan, Atlas, Epimetheus, and Pandora — allowing scientists to solve yet another mystery about our solar system's second-largest planet.

In a new study published in the journal Science on March 28, 2019, the team of 35 researchers, led by Bonnie Buratti of NASA's Jet Propulsion Laboratory in Pasadena, California, reported that the satellites are the result of the accumulation of material from the surrounding rings, which has settled around a dense core. They suspect the core is a remnant of a larger object, which broke apart, resulting in multiple smaller "moons."

NASA's Cassini spacecraft provided scientists with incredible insights about Saturn (Credit: JPL/

The scientists arrived at this conclusion after observing that the moons' surfaces were covered with ice and dust and were highly porous. They maintain the porosity also explains the satellites' ravioli-like shapes, as the material has accumulated around their equators than at their poles.

"We found these moons are scooping up particles of ice and dust from the rings to form the little skirts around their equators," Buratti said. "A denser body would be more ball-shaped because gravity would pull the material in."

As for the different colors? The scientists suggest that Pan and Daphnis, which circle around the innermost red rings, sport a similar hue due to the deposits from the rings. The experts suspect the red material is a blend of organic compounds and iron. Though Atlas, Epimetheus, and Pandora, which are situated on the outside of the massive planet's rings, have similar deposits, they appear blueish. The researchers believe the color is caused by the bright icy particles and water vapor from Saturn's frozen larger moon, Enceladus.

Deposits from Saturn's rings caused its moons to appear either red or blue" (Credit: JPL/

"The daring, close flybys of these odd little moons let us peer into how they interact with Saturn's rings," Buratti said. "We're seeing more evidence of how extremely active and dynamic the Saturn ring and moon system is."

The researchers still have many questions, including what caused the six Saturn moons to form in the first place. The recent discovery has also led them to wonder if other planets sport similar satellites. "Do any of the moons of the ice giant planets Uranus and Neptune interact with their thinner rings to form features similar to those on Saturn's ring moons?" Buratti wonders. "These are questions to be answered by future missions."


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  • bsc
    bscThursday, February 11, 2021 at 6:35 am
    • IceChesMonday, October 28, 2019 at 7:04 am
      Doesn't Saturn technically have, like, 1 million moons if the rings are made of rocks and ice?
      • tdflame5272007
        tdflame5272007Thursday, March 25, 2021 at 5:44 am
        The main rings are much younger than the age of the solar system, perhaps only a few hundred million years old. They may have formed from the breakup of one of Saturn's moons or from a comet or meteor that was torn apart by Saturn's gravity.
      • mcfredbear
        mcfredbearWednesday, October 16, 2019 at 8:54 am
        This is really interesting to me. Esspecially if the "ravioli-shaped" moons are just part of a bigger whole that could've been destroyed over a decade ago! I mean, the possiblities of what happened to create the moons are endless.
        • a-panda
          a-pandaThursday, October 10, 2019 at 6:32 pm
          • girlwhobrowsesz
            girlwhobrowseszThursday, September 19, 2019 at 4:57 pm
            I think that these moons were formed by Saturn's rings, since other planets don't have rings and their moons aren't misshaped (some of them). Plus, Atlas looks like a tiny version of Saturn, sincen it is inside of the rings just like Daphnis and Pan. This is just me made-up theory, and let's hope in the future I am correct! (I just turned 10!)
            • girlwhobrowsesz
              girlwhobrowseszWednesday, December 18, 2019 at 5:06 pm
              I also feel like the moons were forming and Saturn's rings froze it in the process. Saturn's rings are made out of rocks and ice, anyways. Epimetheus is not in the rings and the texture looks normal, unlike the other moons.
              • mcfredbear
                mcfredbearWednesday, October 16, 2019 at 8:51 am
                noice. i tuned 12 over a month ago :/
              • jedid08
                jedid08Monday, August 26, 2019 at 4:47 pm
                • in2th3n3th3r
                  in2th3n3th3rFriday, May 31, 2019 at 5:40 am
                  They kind of look like seashells.
                  • flowerdaisy143
                    flowerdaisy143Tuesday, May 28, 2019 at 1:25 pm
                    • greencrab4
                      greencrab4Monday, May 20, 2019 at 12:28 pm
                      I thought one of thos was ice cream lol
                      • Kazoo kid Tuesday, May 14, 2019 at 1:58 pm
                        MMMM... Makez me hungry