CT/MT: can only Gas Giants have rings?

[Maladominus]

Just curious.

Based on the CT and MT world creation rules, can only gas giants have Saturn-like rings?

How about some roughly Earth-sized planet (say, size 8 or 9 planet) that has a ring of its own? Is this theoretically possible, or simply absurd?

 

[Maladominus]

Just curious.

Based on the CT and MT world creation rules, can only gas giants have Saturn-like rings?

How about some roughly Earth-sized planet (say, size 8 or 9 planet) that has a ring of its own? Is this theoretically possible, or simply absurd?

 

[RandyT0001]

No. You can have rings around terrestial and icy planets as well. Rings form inside a planet's Roche limit. A planet's roche limit depends on the mass of the planet and the mass and composition of the moon. (IIRC)

 

[RandyT0001]

No. You can have rings around terrestial and icy planets as well. Rings form inside a planet's Roche limit. A planet's roche limit depends on the mass of the planet and the mass and composition of the moon. (IIRC)

 

[philippe tromeur]

According to Book 6 - Scouts, Earth-sized planets can't have rings, but Mars-sized planets could (satellite size is Planetary Size - 1D6 ; 0 is a ring).

Strange...

 

[philippe tromeur]

According to Book 6 - Scouts, Earth-sized planets can't have rings, but Mars-sized planets could (satellite size is Planetary Size - 1D6 ; 0 is a ring).

Strange...

 

[RandyT0001]

Well, I didn't read the question correctly and misinterperted it. So I guess Philippe is right, according to Book 6, no, Earth sized planets can't have rings. But in reality I think it depends on the planet's roche limit.

 

[RandyT0001]

Well, I didn't read the question correctly and misinterperted it. So I guess Philippe is right, according to Book 6, no, Earth sized planets can't have rings. But in reality I think it depends on the planet's roche limit.

 

[Malenfant]

Book 6 is somewhat inaccurate

.

All planets can have rings, but how long they last is another matter. Small rocky worlds close to the sun won't have rings that last more than a few thousand years unless there's something actively replenishing them, because (IIRC) tidal forces will whittle them down rapidly. Plus they have smaller roche limits anyway, so it's less likely something will enter them and be disrupted (and the rocky planets are a lot denser than jovians too, which I think makes it more likely that whatever enters the limit won't actually break up)

So rings are a lot less likely for rocky worlds than for jovians. And if you're looking at the chance of a ring being present around a planet at any given moment of a system's history, it's much more likely that a jovian would have one than a terrestrial would because they last a lot longer around the former. Terrestrial can have them, but they're stable for such a brief period before they're gone that chances are you won't see them.

 

[Malenfant]

Book 6 is somewhat inaccurate

.

All planets can have rings, but how long they last is another matter. Small rocky worlds close to the sun won't have rings that last more than a few thousand years unless there's something actively replenishing them, because (IIRC) tidal forces will whittle them down rapidly. Plus they have smaller roche limits anyway, so it's less likely something will enter them and be disrupted (and the rocky planets are a lot denser than jovians too, which I think makes it more likely that whatever enters the limit won't actually break up)

So rings are a lot less likely for rocky worlds than for jovians. And if you're looking at the chance of a ring being present around a planet at any given moment of a system's history, it's much more likely that a jovian would have one than a terrestrial would because they last a lot longer around the former. Terrestrial can have them, but they're stable for such a brief period before they're gone that chances are you won't see them.

 

[Maladominus]

Ahhh thanks for clarifications.

OK, Malenfant. So in the unlikely event that a terrestrial (Earth-like) planet *is* sighted with a ring, then can we assume that it is a fairly young world? Correct?

 

[Maladominus]

Ahhh thanks for clarifications.

OK, Malenfant. So in the unlikely event that a terrestrial (Earth-like) planet *is* sighted with a ring, then can we assume that it is a fairly young world? Correct?

 

[Malenfant]

No, you can assume that the ring system is very young (eg formed by a satellite recently spiralling in within the roche limit). The planet itself doesn't have to be any specific age.

 

[Malenfant]

No, you can assume that the ring system is very young (eg formed by a satellite recently spiralling in within the roche limit). The planet itself doesn't have to be any specific age.

 

[Maladominus]

Originally posted by Malenfant:
No, you can assume that the ring system is very young (eg formed by a satellite recently spiralling in within the roche limit). The planet itself doesn't have to be any specific age.

Aha!!! OK, that was an important distinction.

 

[Maladominus]

Originally posted by Malenfant:
No, you can assume that the ring system is very young (eg formed by a satellite recently spiralling in within the roche limit). The planet itself doesn't have to be any specific age.

Aha!!! OK, that was an important distinction.