Fascinating ideas on the history of Titan and Saturn

Look at Jupiter and you see a mini solar system right down to quasi-analogues of the planets, even a hint of scattered disk and Kuiper Belt objects. But look at Saturn and you see one large Jovian like moon, a hell of a lot of beat to shit frozen moonlets, and billions of icy shards.  The systems surrounding these two planets clearly diverged, violently by the look of it. Now some planetary scientists think they have an idea how it went down out Saturn’s way:

(No Link Yet] — Among the oddities of the outer solar system are the middle-sized moons of Saturn, a half-dozen icy bodies dwarfed by Saturn’s massive moon Titan. According to a new model for the origin of the Saturn system, these middle-sized moons were spawned during giant impacts in which several major satellites merged to form Titan.

Erik Asphaug, professor of Earth and planetary sciences at the University of California, Santa Cruz, will present this new hypothesis October 19 at the annual meeting of the Division for Planetary Sciences of the American Astronomical Society in Reno, Nevada. Asphaug and his coauthor, Andreas Reufer of the University of Bern, Switzerland, also describe their model in detail in a paper to be published in Icarus (in press).

Asphaug and Reufer propose that the Saturn system started with a family of major satellites comparable to the four large moons of Jupiter (known as the Galilean moons, discovered by Galileo in 1610). The Galilean moons account for 99.998 percent of the mass in Jupiter’s satellite system; although it has dozens of small satellites, Jupiter has no middle-sized moons. The new model may explain why the two systems are so different.

I didn’t see this mentioned in the piece, it’s just me FreeThinking, but it sounds plausible that once a system has dozens of icy moonlets careening in the former orbital frames of a Galilean system, a couple might periodically collide every ten or twenty millions years, creating or rebuilding or refreshing a glittering ring system.


  1. F says

    Sure, why not? Such systems frequently kick satellites into different orbits (look at Io). An eccentric orbit may eventually cross another orbit. Early on, like the solar system, there were probably many, many more objects in closely spaced or practically shared orbits. They eventually collide with each other, collide with the sun/planet, get kicked into a different orbit, or get kicked out entirely. (Best explanation for Neptune and Uranus is that they started out this side of Jupiter. Our Moon will eventually leave Earth completely, albeit very, very slowly.)

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