# Tag Info

## Hot answers tagged planetary-rings

33

Io and Jupiter have a very special relationship. Io is a volcanic moon, which ejects charged particles. Due to its relatively low gravity (~0.18g), the particles escape, but they get trapped by Jupiter's immensely powerful magnetic field and form a plasma torus. The density of the plasma is higher close to and ahead of Io. Saturn is like a smaller Jupiter, ...

29

Ever heard of shepherd moons? Shepherd moons are moons (typically not very massive) that orbit in the middle of planetary rings, creating gaps in the material. They also keep the ring material where it is, rather than letting it dissipate: Image courtesy of Wikipedia user The Viewer under the Creative Commons Attribution 3.0 Unported license. Examples of ...

25

is it possible for a planet to have rings made out of water? Of course it is. Just look at Saturn and its ring. The rings of Saturn are the most extensive ring system of any planet in the Solar System. They consist of countless small particles, ranging from μm to m in size, that orbit about Saturn. The ring particles are made almost entirely of water ice,...

14

Yes, you absolutely can have a moon orbiting within a ring system. In fact, we have a perfect example of that in our own solar system: Saturn's A ring has the Encke and Keeler gaps, wherein orbits the moons Pan and Daphnis, respectively. So if you want a ring system with moons orbiting within it, go ahead. If you want to make it realistic, just make sure to ...

11

This is the phase diagram for water. As you can see, it takes pressure for water to be a proper liquid. In a vacuum, it goes straight from solid to gas and vice-versa. It would take approximately 0.6% atmospheres to allow for liquid water. As low as that seems, it is still much more than what you would get in space. But don't give up just yet! ...

10

Yup! This is possible, and a number of small bodies in the Solar System have rings: Haumea, a dwarf planet in the outer Solar System, was recently discovered to have rings, which lie inside its Roche limit. Chariklo, a very large asteroid, has two known rings. Chiron, another minor planet, is suspected to have rings, but these have not been confirmed. ...

9

You've asked three very distinct questions here. I'll try to answer them all. Could this scenario even happen with Earth's gravity and atmosphere? I doubt it. For one thing, most of the ring material would burn up in the atmosphere, much as meteors and deorbiting satellites do, never reaching the ground. Second, even if you manage to handwave the ...

8

No effect at all. Gravitational influence on its own is not enough, you must have variations to create tides. In a ring, the mass is distributed equally in a symmetrical shape. To turn the question on its head, can the tides have an effect on the rings? Yes, if one or more moons are orbiting the planet, they can make waves in the rings, like just visible ...

8

For the most part, rings should not be much of an issue. Most of the rings we know of in our own solar system are made of dust and ice, and outside of Saturn, most of these rings are fairly nebulous. A spaceship moving at orbital or even interplanetary velocity will have a reasonably low chance of impacting anything large (and larger objects like shepherd ...

8

Before I begin, we need this picture: That's the Earth and our moon. OK, simple answer: Rather than Earth's tilted axis, we have an axis of rotation that perpendicular to the planet's orbit (0° to the ecliptic plane). Rather than Earth's moon, which does not orbit the equator but has a fairly complex orbit, we're going to assume a ring that's circular and ...

7

Not naturally. If the rings intersect, they'll clearly knock each other out of the sky. So for this to even be plausible, you'd need one ring at a distance and another ring close in. But rings are in orbit -- they're constantly orbiting the planet. And the rate of their orbit affects how far out they are. Particles tend to lose energy over time and fall ...

7

First of all, realize that the rings themselves cast their own shadow on the planet. Here is a photo of Saturn during a time that the sun is at a rather oblique angle. If you live in those shadows the sun appears obscured by the rings. The shadows are constant, but the effects at any one spot on the planet within tens of degrees of latitude (depending on ...

7

If the Earth had Saturn-like rings, you would not have to worry about falling debris. As you mentioned, the area under rings that were created (relatively) recently could be hazardous due to falling debris landing on the planet. However, this is not the case for Saturn's rings: Size of debris: Saturn's rings are mainly composed of particles measuring 1cm ...

7

This is unstable See the Edit We know that binary stars can orbit around one another similar to what you're doing with your ring-o-worlds. They orbit around a central "center of mass" point. It has been suggested that anywhere from half to nearly all star systems are multiple-star systems, including systems of 3 or more stars. Therefore, it's possible ...

6

On Earth, a lot of satellites are in low-Earth orbit. This extends out to 2,000 km, which is a safe distance away from the innermost part of the rings around your world. So you can put satellites into orbit around your world in the same way that we put satellites into orbit around Earth. Medium Earth orbit satellites would have to worry about the rings, but ...

6

I'm not an expert, but I did a little searching and this is how I believe that planetary rings act: To start off, I believe that rings in general will be equatorially bound in general. Rings are formed when a moon or other small object (relative to the planet) gets orbits in too close and is utterly destroyed by the immense gravity of the planet. The ...

6

I think the result will be very similar to what happens here on this Earth during a solar eclipse. I like this quote from http://www.eclipse2017.org/2017/what_you_see.htm: You'll get the shrinking sliver of Sun, which is kind of cool but is not the real show. As the sliver thins, though, you get the very weird atmosphere that surrounds an eclipse, which ...

6

The requirement of a compass behaving sensibly is that a planet has a reasonably smooth bi-polar magnetic field. Under such circumstances the lines of force always point towards one of the magnetic poles on the planet's surface, and therefore the compass always points in the same direction. You also mentioned fauna. The Earth's magnetic field is a vital ...

6

It is important to note that the zero pressure of the vacuum is below the water's triple point. Below the triple-point pressure, water can either exist as vapor or as solid, but not a liquid. That is why there is no surface liquid water on Mars, in-spite of abundant ice caps. In other words, when you heat a chunk of ice in space, it just evaporates without ...

6

I'm new here too! I have no idea why you want aquatic amphibians on a water-world tidally locked with its star and surrounded by a dust/ice ring, but let me know how the below sounds! Rings aren't generally orbitally stable at all; they typically have shepherd moons keeping them from aggregating into a satellite, falling into progressively lower orbits, or ...

6

Saturn’s moon Rhea may have rings, and while it’s not been confirmed, the fact that astronomers are considering it shows that they believe it’s possible for a moon to have rings.

5

For reference, here is an image of Saturn, where you can clearly see the shadow cast by the rings on the planet's surface: As you can see, the shadow is quite dark. It's also quite wide. If you were standing in the middle of that shadow, at that time of year, the sun would be entirely covered by the rings for many miles in every direction, and you would ...

5

A picture is worth a thousand words. Check the leftmost part of it. Click for a bigger picture (this is the source). And the source article as well. Edit: HDE's answer also uses Saturn's moons for an example, and his answer is even better.

5

I don't have a great grasp on the physical sciences, so I'll focus on some economic possibilities: The appearance of exotic goods: Not every good follows the normal rule that higher prices mean fewer sales. For a small category of luxary goods, higher prices actually mean more sales. Even if the goods are otherwise identical in nature to conventional ...

5

There isn't one. I'll use the rings of Saturn, the largest ring system in the solar system, for an example. First, there isn't much there. Estimates are 3 to 21 x 1019 kg, or about 1/1000th the mass of the Moon. That's nothing to sneeze at, but it's a long way to go for not a lot of material. Saturn has seven moons with more mass, FAR more mass. ...

5

No need to blow it up, just give it a gentle push to the edge of earths Roche Limit. The gravitational pull will slowly tear it apart and create an awesome ring. I've grown tired of the moon anyway, so I endorse this plan. Risk of huge chunks of the moon crashing into the earth is a minor concern. This article covers your question quite well

5

This has indeed been investigated. I found a thesis by Daniel Jontof-Hutter (2012) that did a stability analysis of particles in rings orbiting, among other bodies, Saturn. One important quantity he studied was the ratio of electric force to gravity, $L_*$. When $L_*\gg1$, the electric force dominated (the "Lorentz regime"), while when $L_*\ll1$, the ...

5

No, the rings would not be able to cause tides. The tides are caused because of what we call a "gravitational differential". Basically, what this means is that the Moon pulls on the near side of the Earth more than it pulls on the far side. This is a result of how gravity falls of with distance: $$F_g = \frac{GMm}{r^2}$$ The force of gravity falls off ...

5

The answer to your question is yes but. It is certainly possible for a moon of a giant planet to have a ring, but the key word in your question is “stable”. What do you mean by stable? A year, a century, a millennia, 50 millennia, a million years? Any of these might be considered “stable” at some level. The problem is that asking how long such a ring ...

5

A few things to think about: The rings would be in the plane of axial rotation, that is, right above the equator. So how it would look depends greatly on where you live on the planet. If you live on the equator for instance the rings will always look like a thin line in the sky. As you move away from the equator the rings would expand until you reach far ...

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