Picture if You Will...

[Supreme]

Imagine that there is a large planet with a moon that are reasonably far from their sun. The moon is made of mostly elements like Oxygen and Nitrogen, but frozen solid. However, the moon is so close that the gravitational forces continuously knead the moon causing it to:

 

a. liquify then boil the core of the Nitrogen/Oxygen moon, the resulting vulcanism expels massive amounts of super-hot nitrogen and oxygen

 

b. said super-hot gases are then sucked down in a continuous stream to the larger planet below

 

Obviously, the moon wouldn't last long. However, by human standards a million years (let's say the moon was recently acquired) is quite long. Could you, if you had the technology, set up some kind of floating city in that stream of cooling nitrogen and oxygen?

 

I call it "Haven".

[Fuzzy Gnome]

Re: Picture if You Will...

 

I think the oxygen and nitrogen would be more likely to form a ring around the planet, as there's no reason for the gas to just stop in its orbit and fall to the ground, even if the tides are outrageous. If some of the expelled gas gets spewed with enough force to break orbit and land on the planet, some will also get expelled in all other directions and uselessly disperse.

Consider an accretion disk around a black hole. Bodies approaching too closely get pulled apart by tides; material falling off such bodies continues to orbit until collisions with other matter causes it to spiral in.

Maybe you can have a station in a Lagrangean point where ejected gas accumulates at a slightly higher concentration than elsewhere.

[Nyrath]

Re: Picture if You Will...

 

a. liquify then boil the core of the Nitrogen/Oxygen moon, the resulting vulcanism expels massive amounts of super-hot nitrogen and oxygen

You are aware, are you not, that "super-hot" is relative?

Molten nitrogen is still so cold that it would freeze you solid. I'm sure you've seen that trick where the chemist dips a rose into liquid nitrogen. Then they tap the rose on the table and it shatters.

 

The same goes for molten oxygen.

 

If you heated both to, say, red-hot temperatures, they would of course turn into hot gas.

[Dr. Anomaly]

Re: Picture if You Will...

 

Just curious Supreme, but have you ever read Smoke Ring by Larry Niven?

[Basil]

Re: Picture if You Will...

 

Imagine that there is a large planet with a moon that are reasonably far from their sun. The moon is made of mostly elements like Oxygen and Nitrogen' date=' but frozen solid.[/quote']

That would hang my disbelief, rather than suspend it. Oxygen and nitrogen, sans ammonia and water would have a vanishingly small chance of accumulating in moon-sized chunks. Absent organic processes---forget it.

 

However' date=' the moon is so close that the gravitational forces continuously knead the moon causing it to:[/quote']

It is not mere closeness that would cause this (*), but an elliptical orbit, which requires explaining. Another moon? The planet's own orbit is highly elliptical, and the sun perturbs the moon? A "lock" with another (probably larger) planet? Only the first strikes me as at all likely.

 

a. liquify then boil the core of the Nitrogen/Oxygen moon' date=' the resulting vulcanism expels massive amounts of super-hot nitrogen and oxygen[/quote']

Wouldn't need to reach boiling point at all---once the liquid is expelled into space (**), it will boil off rapidly.

 

b. said super-hot gases are then sucked down in a continuous stream to the larger planet below

As has been pointed out, this requires losing a good deal of kinetic energy. However, mutual collisions within the ring of gas will lead to this happening, slowly but surely. Though the term "stream" wouldn't fit.

 

Obviously, the moon wouldn't last long. However, by human standards a million years (let's say the moon was recently acquired) is quite long. Could you, if you had the technology, set up some kind of floating city in that stream of cooling nitrogen and oxygen?

 

I call it "Haven".

If you had the technology, you certainly could do that and more.

However, parking "Haven" at the L4 or L5 point would be much simpler.

 

(*) Closeness could cause the whole moon to break up (if it's within the Roche Limit), but I don't think that's what you want.

(**) There's the problem of getting the liquid off the moon; this requires enough energy to accelerate a useful fraction of the liquid to the escape velocity. Despite the increadable power of Io's volcanoes, only a minute fraction gets off of Io.

[Supreme]

Re: Picture if You Will...

 

You are aware, are you not, that "super-hot" is relative?

Molten nitrogen is still so cold that it would freeze you solid. I'm sure you've seen that trick where the chemist dips a rose into liquid nitrogen. Then they tap the rose on the table and it shatters.

 

The same goes for molten oxygen.

 

If you heated both to, say, red-hot temperatures, they would of course turn into hot gas.

I'm aware. I was thinking, "heated well past the boiling point."

[Supreme]

Re: Picture if You Will...

 

That would hang my disbelief' date=' rather than suspend it. Oxygen and nitrogen, [u']sans ammonia and water[/u] would have a vanishingly small chance of accumulating in moon-sized chunks. Absent organic processes---forget it.

Well, other substances, such a ethly alcohol, can accumulate in large, nearly pure clouds. If an accretion disk spins fast enough, can't it act as a sort of centrifuge? Maybe not oxygen (O2), but Carbon Dioxide which would be enough to keep the inhabitants of Haven warm and not-exploding from decompression. They can incorporate plants to get O2 from the CO2.

It is not mere closeness that would cause this (*), but an elliptical orbit, which requires explaining. Another moon? The planet's own orbit is highly elliptical, and the sun perturbs the moon? A "lock" with another (probably larger) planet? Only the first strikes me as at all likely.

I don't have a problem with the presense of other moons. I based this idea upon Io, which has gravitational-force-based vulcanism.

Wouldn't need to reach boiling point at all---once the liquid is expelled into space (**), it will boil off rapidly.

Well, it turns to gas, but iss too cold for biological processes, right?

As has been pointed out, this requires losing a good deal of kinetic energy. However, mutual collisions within the ring of gas will lead to this happening, slowly but surely. Though the term "stream" wouldn't fit.

But would the people of Haven be able to breathe without space-suits?

If you had the technology, you certainly could do that and more.

However, parking "Haven" at the L4 or L5 point would be much simpler.

Unfamiliar with L4 or L5, but it sounds like you are referring to Lagrange points between the two gravities?

(*) Closeness could cause the whole moon to break up (if it's within the Roche Limit), but I don't think that's what you want.

(**) There's the problem of getting the liquid off the moon; this requires enough energy to accelerate a useful fraction of the liquid to the escape velocity. Despite the increadable power of Io's volcanoes, only a minute fraction gets off of Io.

Of course, in my example, the material being expelled is less dense, isn't it?

[Curufea]

Re: Picture if You Will...

 

Don't these elements sublimate? Skipping the liquid state entirely?

[Bucky]

Re: Picture if You Will...

 

That depends on the atmospheric pressure and temperature. Assuming this is cold, deep space, then yeah. Those elements will sublimate.

 

You might want to look at the ratio of the gravitational force between the sun and the planet in the region of the moon's orbit. I can't remember what is a good number, but remember that any expelled gas will face a tug of war between the sun's gravity (Also its solar wind, which can be dampened a whole lot by the planet's magnetic field) and the planet's gravity. So while the gas may escape the moon, it might not escape the planet's field, and hence form a ring that the moon is moving through.

 

It may not be that young a moon after all. Just continually churning, expelling gas that gets trapped to rain back down on the moon, while forming very pretty rings around the planet.