Is there some prediction of the speed of rings?

In summary: So it's possible, but not likely.In summary, the inner parts of the rings move around Saturn faster than the outer parts, all in accordance with Kepler’s third law for small objects revolving about a massive, larger one. They orbit the planet with periods ranging from 5.8 hours for the inner edge of the C ring, to 14.3 hours for the outer edge of the more distant A ring. Since Saturn spins about its axis with a period of 10.6562 hours, the inner parts of the main rings orbit at a faster speed than the planet rotates, and the outer parts at a slower speed.
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Prometeus
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From NASA page:

The inner parts of the rings move around Saturn faster than the outer parts, all in accordance with Kepler’s third law for small objects revolving about a massive, larger one. They orbit the planet with periods ranging from 5.8 hours for the inner edge of the C ring, to 14.3 hours for the outer edge of the more distant A ring. Since Saturn spins about its axis with a period of 10.6562 hours, the inner parts of the main rings orbit at a faster speed than the planet rotates, and the outer parts at a slower speed.

Now my questions:

Why are the inner rings moving faster than rotation of Saturn?

Is there some expected relation between the rotation of a planet (or asteroid) and rotation of the particles in the rings?

Or is the speed of rings rather related to the gravity of the planet (or asteroid) and not related to rotation of the planet?
 
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The rings are just particles in orbit. Their speed is a function of distance, as the NASA page says, and it has nothing to do with the planet's rotation. Just like our satellites.
 
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A ring is nothing more than a large number of small objects in orbit around a planet. Orbital velocity is a function of distance from the planet. At small distances the orbital velocity must be greater than at larger distances for a body to remain in orbit. A body in orbit cannot exceed escape velocity and remain in orbit, so there is a limited range of velocities permitted for objects forming a planetary ring. When orbital velocity equals the projected rotational speed of a planet at any particular distance ti achieves a synchronous orbit. Around Earth this is known as a geosynchronous orbit. This speed must increase with distance from the planet.without exceeding its escape velocity. A geostationary orbit is always in a geosynchronous orbit but not the other way around.
 
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Chronos said:
A ring is nothing more than a large number of small objects in orbit around a planet. Orbital velocity is a function of distance from the planet. At small distances the orbital velocity must be greater than at larger distances for a body to remain in orbit. A body in orbit cannot exceed escape velocity and remain in orbit, so there is a limited range of velocities permitted for objects forming a planetary ring. When orbital velocity equals the projected rotational speed of a planet at any particular distance ti achieves a synchronous orbit. Around Earth this is known as a geosynchronous orbit. This speed must increase with distance from the planet.without exceeding its escape velocity. A geostationary orbit is always in a geosynchronous orbit but not the other way around.

Thanks. So it is just a function of distance, escape velocity and gravity of the planet. The expected speed of rings has nothing to do with the rotational speed of planet.
 
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Correct, the ring speed is unrelated to the rotation speed of the planet it orbits
 
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So perhaps the question could be rephrased as, “Why is the surface of the planet rotating more slowly than the inner rings?”, right?

After all, if the planet formed from local materials that got pulled into orbit around a common center of gravity, then their speed should have been determined by the same dynamics as the materials in the rings. But that doesn’t seem to be the case. The same could be said of Earth, although I’ve heard that in our case, gravitational breaking is the reason. If we have been slowed down by the drag from our moon, is that what is believed to have happened to Saturn, as well?
 
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LURCH said:
So perhaps the question could be rephrased as, “Why is the surface of the planet rotating more slowly than the inner rings?”, right?

After all, if the planet formed from local materials that got pulled into orbit around a common center of gravity, then their speed should have been determined by the same dynamics as the materials in the rings. But that doesn’t seem to be the case. The same could be said of Earth, although I’ve heard that in our case, gravitational breaking is the reason. If we have been slowed down by the drag from our moon, is that what is believed to have happened to Saturn, as well?
It's been a few years since I read about rings, but from what I remember, their depletion rate is too high for them to be primordial. I think the model was along the lines of a breakup of a small orbiting body (either collisionally or tidally), and subsequent flattening of the debris through an interplay of self-gravity, collisional dynamics and tidal acceleration.
 

Related to Is there some prediction of the speed of rings?

1. What factors affect the speed of rings?

The speed of rings is affected by several factors such as the material and size of the ring, the force applied to it, and the surrounding medium (e.g. air, water, etc.). The speed can also be influenced by external factors like temperature and pressure.

2. Can we accurately predict the speed of rings?

Yes, scientists have developed mathematical models and equations to predict the speed of rings based on the aforementioned factors. However, these predictions may not always be 100% accurate as there are many variables that can affect the speed.

3. How is the speed of rings measured?

The speed of rings can be measured using various techniques such as high-speed cameras, laser sensors, and pressure sensors. These devices can capture the movement of the rings and calculate their speed based on the distance and time traveled.

4. Is the speed of rings constant?

No, the speed of rings is not constant as it can vary depending on the factors mentioned earlier. For example, the speed of a ring may decrease as it travels through a denser medium like water compared to air.

5. Why do we study the speed of rings?

The study of the speed of rings has various applications in fields such as fluid dynamics, engineering, and meteorology. Understanding the factors that affect the speed of rings can help us design more efficient and effective systems, as well as better predict and track the movement of objects in different mediums.

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