(ORDO NEWS) — Of all the rings in the solar system, those of Saturn are arguably the most impressive.
Unlike the thin rings of dust and rock surrounding Jupiter, Uranus, Neptune, and even the Kuiper Belt dwarf planet called Haumea, Saturn’s colorful ring system is a magnificently vast thing.
Dotted with tiny moons that form its edges, it is a complex structure with seven rings each moving at different speeds.
Interestingly, the very disk that Saturn is famous for seems strikingly young. The available evidence suggests that the ring system is only 100 million years old, give or take (and additional evidence suggests that they will disappear in less than 100 million years).
Why the rings appeared so long after the rest of the formed solar system is difficult to explain, leading some scientists to question the correct interpretation of these data.
Now, as a by-product of researching some other features, the team has come up with a plausible answer.
If Saturn’s rings are composed of a crushed moon, this could explain not only the recent acquisition of dusty disks, but also two other strange features of the ringed planet: its axial tilt and the strange, rapidly expanding orbit of its largest moon, Titan.
Every planet in the solar system has an axial tilt, which is the angle between the axis of rotation and the plane of the orbit.
Everyone is also different. Saturn shows 26.7 degrees which is similar to the tilt of Earth, Mars and Neptune. However, the tilt of the gas giant is becoming more extreme, which scientists attribute to Titan’s outward migration.
According to previous studies, the chain of gravitational interactions from Saturn to Titan and Neptune had a significant impact on the tilt of the surrounding world.
The rate at which Saturn oscillates around its axis of rotation (rotational precession) is very close to the rate at which Neptune’s entire orbit oscillates (orbital precession). the study found that, unlike earlier studies, these gravitational steps must have converged relatively recently, given that Titan is migrating away from Saturn too quickly for them to have originated in the early solar system.
New However, the work of a group led by astronomer Jack Wisdom of the Massachusetts Institute of Technology has found something strange.
They used gravity data from NASA’s Cassini spacecraft and a model of the planet’s internal structure to see if Saturn is still in resonance with Neptune. Answer? Not really.
It was curious, so they dug deeper to try and figure out why. If Titan’s orbit first migrated outward as expected and then unexpectedly changed, this could pull Saturn in and push it back out of resonance, resulting in the current not-quite-resonance with Neptune.
The next step would be to figure out what could have changed Titan’s orbit so dramatically. Well, we know that Saturn has a hell of a lot of moons.
Currently, at 82 (including some not yet confirmed), it has the largest known number of moons in the solar system. If Saturn had an extra moon that became destabilized, this could change the planet’s precession and help it avoid resonance with Neptune.
The team ran hundreds of Saturn simulations with slightly different starting conditions. system, including this hypothetical moon named Chrysalis. And they found that this scenario clearly explains everything – the axial tilt, Titan’s orbit, and even Saturn’s baby rings.
In particular, the scenario suggests that the presence of the Chrysalis may have caused Saturn to lean the other way. more than we see now, about 36 degrees, due to the resonance with Neptune. At this time, he was supposed to have a gravitational interaction with Titan.
Then, about 160 million years ago, Chrysalis’ orbit destabilized. This caused it to veer too close to Saturn, whose gravity tore the moon apart.
Researchers estimate that about 99 percent of the Chrysalis eventually crashed into Saturn. , but enough material remained in orbit to form the planet’s rings.
If the moon were icy, like some of the solar system’s moons, this could lead to the observed abundance of ice in the Rings of Saturn today.
This violent collision could also have brought Saturn out of resonance by reducing its axial tilt. However, out of 390 simulations, only 17 gave the conditions under which Saturn’s rings formed.
So, as Cornell University astronomer Mariam El Mutamid explains in a commentary on a new study, while the destruction of Chrysalis is possible and plausible, although it was probably a rare, isolated occurrence. We are unlikely to see another such event in the near future.
“We hypothesize,” the researchers write in their paper, “that Saturn once had an additional moon, Chrysalis; that the system was previously in spin-orbit precessional resonance with Neptune; that Saturn’s tilt has increased as the rate of precession has changed due to Titan’s migration; that it escaped precessional resonance due to the instability of the Chrysalis orbit; and that the close encounter of this hypothetical moon with Saturn resulted in the formation of its rings.”
“It’s a pretty good story,” says Wisdom, “but like any other result, it will have to be studied by others.”
However, he explains things that have been difficult to understand until now. Future studies of the surprisingly complex system of Saturn and other ring systems may help determine the speed at which events such as the destruction of Chrysalis are expected.
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