Because Jupiter is larger, it should have larger and more spectacular rings than Saturn’s. But new research from UC Riverside shows that Jupiter’s massive moons prevent vision from lighting up the night sky. I’ve long wondered why Jupiter doesn’t have even more amazing rings to put Saturn to shame,” said UCR astrophysicist Stephen Kane, who led the research. “If Jupiter had them, they would appear even brighter to us because the planet is much closer than Saturn.” Kane also had questions about whether Jupiter once had fantastic rings and lost them. Ring structures can be temporary.
To understand why Jupiter looks the way it does right now, Kane and his graduate student Zhexing Li ran a dynamic computer simulation that takes into account the orbits of Jupiter’s four main moons, as well as the orbits of the planet itself and information about the time it takes for will form rings. Their results are now online and will soon be published in the journal Planetary Science.
Saturn’s rings are largely made of ice, some of which may have come from comets that are also largely ice. If the moons are massive enough, their gravity can eject the ice from the planet’s orbit or change the ice’s path enough to collide with the moons.”We found that the Galilean moons of Jupiter, one of the largest moons in our solar system, would very quickly destroy any large rings that might form,” Kane said. Consequently, Jupiter is unlikely to have had large rings at any point in its past.
Massive planets form massive moons, which prevents them from having substantial rings,” Kane said. All four giant planets in our solar system—Saturn, Neptune, Uranus, and also Jupiter—actually have rings. However, both Neptune and Jupiter’s rings are so faint that they are difficult to observe with traditional stargazing instruments. Coincidentally, some of the recent images from the newly commissioned James Webb Space Telescope included images of Jupiter showing faint rings.
“We didn’t know these ephemeral rings existed until the Voyager spacecraft flew by because we couldn’t see them,” Kane said. Uranus has rings that are not as large but more substantial than Saturn’s. Going forward, Kane intends to run simulations of conditions on Uranus to see what the lifetime of the planet’s rings might be. Some astronomers believe that Uranus is flipped on its side as a result of the planet colliding with another celestial body. His rings could be a remnant of that impact.
In addition to their beauty, the rings help astronomers understand the planet’s history by offering evidence of collisions with the moon or comets that may have occurred in the past. The shape and size of the rings, as well as the composition of the material, tells us about the type of event that created them.” For us astronomers, it’s blood spatter on the walls of a crime scene. When we look at the rings of giant planets, it’s evidence that something catastrophic happened to that material,” Kane said.
Source Reference: Stephen R. Kane, Zhexing Li. The Dynamical Viability of an Extended Jupiter Ring System. Planetary Science (accepted), 2022 [abstract]
