Findings of a new research have suggested that Saturn had a crucial role in the formation of Jupiter's largest moons.
The Galilean Moons
Jupiter's largest moons, Europa, Io, Ganymede, and Callisto, are the so-called Galilean moons. They are all bigger than planet Pluto. Earlier studies also suggested that two of these satellites, Callisto and Ganymede, possibly have water oceans beneath their icy crust, which raises the idea that they can potentially host life.
Many astronomers think that most, if not all of the smallest moons of Jupiter, came to the solar system from elsewhere. The Galilean moons, however, are thought to have originated near the gas giant itself.
How Jupiter's Biggest Moons Formed
Earlier studies suggest that the giant moons originated from the disk of matter that surrounded Jupiter during the planet's last stages of formation, but it is not clear where the building blocks of this disk were from and how these have come to surround the gas giant.
Jupiter opened up a gap in the protoplanetary disk, the circumstellar disk of dense gas, and dust that surround the young sun, when it formed. This should have isolated the young gas planet from the rest of the disk, raising questions as to how Jupiter was able to collect enough amount of solid material that formed the Galilean moons.
Astrophysicist Thomas Ronnet, from Aix Marseille University, and colleagues decided to look into this matter using computer models of the gap that formed in the disk to learn what happened as Jupiter and nearby planets formed.
Simulations revealed that at the outer edge of the gap, a reservoir of planetesimals, the building blocks of planet, collected overtime. The simulations also showed that Saturn's core may have formed within the planetesimal reservoir or migrated through it.
Saturn's gravitational pull then dispersed the planetesimals toward Jupiter and the inner solar system, which offers feasible explanation as to the origin of the solid materials that formed Jupiter's large satellites.
"The formation of Saturn's core within this reservoir, or its prompt inward migration, allows planetesimals to be redistributed from this reservoir towards Jupiter and the inner Solar System, thereby providing sufficient amount of material to form the Galilean satellites," the researchers wrote in their study, which was submitted to The Astrophysical Journal on April 9.
Giant Moons Tend To Form In Multiple-Planet Systems
Results of the simulations showed that giant moons such as Jupiter's Galilean satellites tend to form around planets within multiple-planet systems such as the solar system instead of in systems with lone or isolated planets.
