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#1 2012-07-06 15:52:29

Terraformer
Member
From: Lancashire
Registered: 2007-08-27
Posts: 3,063
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Developing Saturn

Saturn is, as been pointed out by Winchell Chung (and picked up by Rick Robinson), the best place in the solar system for a hard Sci-Fi setting, as it has rings (giving an excuse for space fighters), a single large moon and six smaller dwarf moons (which can be treated as planetary colonies) and quick trip times and low delta-V's between them (meaning tramp freighters utilising chemical can be used).

Here's a couple of links to help:
http://www.projectrho.com/public_html/r … aiders.php
http://www.rocketpunk-manifesto.com/201 … rings.html

Mulling over how to make a low budget Sci-Fi series in the vein of Firefly (but without handwavium), I decided that Saturn would be an ideal location. I'm already thinking that each major world would be terraformed with a hybrid worldhouse, and perhaps some of the minor worlds (such as Janus) would be sculpted and worldhoused as well. Perhaps using magnets we'll be able to simulate gravity... also, ringworlds and Bernal spheres could be built?

Any other ideas? I'd like to build this system.


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#2 2012-07-06 20:17:20

Midoshi
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From: Colorado
Registered: 2007-07-14
Posts: 155

Re: Developing Saturn

I'd just add that Saturn lacks the intense radiation belts that Jupiter has, making long term operation of electronics (and biology) possible without massive amounts of shielding. As long as you are beyond 4 Saturn radii, or approximately Enceladus and further, you don't need to worry as much about the radiation belts. On the other hand, Saturn's magnetic field shields the moons from solar and cosmic rays, which is convenient since none of them have their own magnetic field.


"Everything should be made as simple as possible, but no simpler." - Albert Einstein

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#3 2013-11-18 09:31:43

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Developing Saturn

The radiation is above the atmospheres of either planet in any case. The radiation belts of Jupiter and Saturn are in space, as they are charged particles from the Sun collected by those magnetic fields. In the atmosphere they would lose their charges and would no longer be radiation. Jupiter is an unfriendly environment because of its high gravity, while Saturn's is almost the same as Earth's gravity.

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#4 2013-11-19 00:59:14

JoshNH4H
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From: Pullman, WA
Registered: 2007-07-15
Posts: 2,513
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Re: Developing Saturn

I think he was talking about various orbital objects and not the planet itself.


-Josh

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#5 2013-11-19 11:42:57

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Developing Saturn

What do you think of the fictional planet Polyphemus and satellite Pandora from the movie Avatar? How realistic is such a set up?
I've heard that gas giants are just about ruled out in the Alpha Centauri System, but in case there was one how realistic would that be? Polyphemus' radiation environment would probably be even more lethal than Jupiter as it sits right in the habitable zone Pandora has a gravity of about 0.8 of Earth.

http://james-camerons-avatar.wikia.com/wiki/Pandora


Avatar
Diameter     11447 km
Mass     0.72 Earths
Gravity     0.8 g
Atmospheric density     1.2 Earths
Surface pressure     0.9 atm

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#6 2013-11-20 01:11:58

JoshNH4H
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From: Pullman, WA
Registered: 2007-07-15
Posts: 2,513
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Re: Developing Saturn

Well in the general sense (e.g. not Alpha Centauri per se but a star somewhere) I see no implicit reason why the formation of such a body would be impossible.  Having said that I don't know much about the orbital mechanics of moon formation.  It's not inconcievable to me that simulation would suggest that the formation of a body that large wouldn't be possible because that much material would be unlikely to clump in one place.

I don't know, and given no additional information I'd say it's possible unless told otherwise. I've always been of the opinion that a very large portion of the habitable bodies out there are actually moons of gas giants or dual planet systems orbiting red dwarfs, simply because there are so many red dwarfs.


-Josh

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#7 2013-11-20 12:57:52

Void
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Registered: 2011-12-29
Posts: 3,011

Re: Developing Saturn

I think it is supposed to be a percentage of the planets size if it is formed from the planets disk.  1%????  Couldn't find the reference, any query for moon brings up our Moon.  So the bigger the planet, the bigger the moon mass.  However if Jupiter had one big moon instead of Io, Europa, Ganeymede, and Callisto, maybe that would be getting substantial.

But a planet many times bigger than Jupiter might do much better.

Then there is our moon which did not form that way apparently.  I have my own rogue notion of how it formed, I think it was condensed from the Earths spare material first as a wet object, and then was added to by rubble from impacts with the Earth.  I think that is why there is evidence of magmatic water.  I will not duke it out on that speculation however.

Then there is Triton, where it is thought it was captured.  Most likely method, was that it was a binary object, and it's partner was either ejected, or impacted Neptune.  So, maybe if you have a chaotic system forming with binary objects changing orbit, you could get a more substantial moon than if it
was a condensed moon, but it appears that that is not a common occurance.

Last edited by Void (2013-11-20 13:01:25)


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#8 2013-11-20 14:51:59

Terraformer
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From: Lancashire
Registered: 2007-08-27
Posts: 3,063
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Re: Developing Saturn

Mmmm, the figure I've seen is 10^-4 for the size relation - so 1% of 1% of the primary's size. That doesn't hold true for Terra - or maybe it did, and the giant impact theory is wrong...


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#9 2013-11-20 22:19:29

JoshNH4H
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From: Pullman, WA
Registered: 2007-07-15
Posts: 2,513
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Re: Developing Saturn

Of course, it's not totally  inconceivable that the proplyd was hit witha giant impactor that turned into a rocky moon.  That's one way you might get a carbon planet forming.  This would be more for ice Giants like Uranus and Neptune.

Even more unlikely on the scale of things would be an aerocapture type maneuver in the proplyd.  Now just imagine getting to watch that!


-Josh

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#10 2013-11-21 00:32:58

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Developing Saturn

Do you know of any G, K, or F main sequence stars that have M class red dwarf stars orbiting in circular orbits within the habitable zone of the more massive companion?
Proxima Centauri has the mass of 80 Jupiters, if it were orbiting a G2 V class star what would the habitable zone be for a moon with 80 times the mass of Io+Europa+ Ganymede+ Callisto? and how big would such a body be it that mass were primarily rock? You'd want a day to be around something like 24 to 100 hours

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#11 2013-11-21 02:36:56

Terraformer
Member
From: Lancashire
Registered: 2007-08-27
Posts: 3,063
Website

Re: Developing Saturn

Well, you wouldn't be talking about somewhere that humans could settle, since such a planet would have a mass several times that of Terra, and a surface gravity of ~1.5g. Or maybe even more than that, possibly up to 2g - the galileans are bigger than Luna, after all, and Luna has a mass of 1/81th Terra.

But an M dwarf in the habitable zone of a star? You're going to be getting a lot of heat on it's planets, especially if they're orbiting close enough to do it in a day (HINT: there's a good chance they'd be molten). Maybe you could do it with a brown dwarf, though.

But with such a massive body, you should be able to stick significant masses at the L4 and L5 points and have them be stable. Say, a 40 jupiter mass brown dwarf, orbited by several terrestrial planets, and a Jovian in both L4 and L5, each orbited by terrestrial moons, and all of them be habitable. That's a lot of habitable worlds in one system, and the magnetic fields around their primaries offer lots of power for stuff like magbeam launch systems to go from sector to sector. Of course, in sector you'd be able to get away with chemical. Bonus points if the terrestrial worlds around the brown dwarf also have habitable moons.

An actually existing system that is somewhat similar is Epsilon Indi, with a binary brown dwarf system (separation ~2AU) that's 1,500AU away from a K-class star of similar metallicity to Sol (so, possibly terrestrial planets). It's a long journey between them, about 225 billion kilometers, but we should be able to manage it if we've got there in the first place. A few months travel at 0.1c, and it would take just over a week to receive news without an ansible.


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#12 2013-11-21 19:00:13

JoshNH4H
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From: Pullman, WA
Registered: 2007-07-15
Posts: 2,513
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Re: Developing Saturn

If anything I would say the Jovian system is fairly amenable to this kind of inter"planetary" civilization, insofar as the bodies are fairly close to each other and don't have too high delta-Vs to get from one to the other.  There's also, ya know, four of them smile

If in the context of a story someone wanted to terraform the four moons you'd have a pretty good basis for a rocketpunk story.


-Josh

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#13 2013-11-22 01:37:21

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Developing Saturn

Speaking of rocketpunk
http://en.battlestarwiki.org/wiki/The_T … s_of_Kobol
Here you have a quadruple star system with 12 Earthlike planets, to keep the system relatively compact, it is composed of a pair of binaries in circular orbits around each other, and the binaries themselves are also in circular orbits around each other.

The Twelve Colonies are situated within the star system Cyrannus, located some 2,000 light years from Kobol, where humanity presumedly first evolved. All in all, Cyrannus is a vast and complex system, comprised of four [4] stars: Helios Alpha, Helios Beta, Helios Gamma, and Helios Delta. Each star is orbited by its own family of planets and other astronomical bodies. The stars come together to form two binary systems (Alpha/Beta and Gamma/Delta). Both pairs of stars then orbit each other around a third, central barycenter every 546,892 years. Both binary systems are separated by 0.16 light years or 10,091 Stellar Units, shortened to SU (In this case, 1 SU being equal to the average distance between Helios Alpha and the barycenter of the Caprica-Gemenon binary, roughly 150 million km).

I'll bet that somewhere in the Milky Way Galaxy, there is a system like this, out of 100 billion stars, there might even be 12 Earthlike planets, but only Earthlike by the fact that each of them are in their respective star's habitable zone and each planet has approximately the same mass as the Earth, with diameters between 12,000 km and 13,000 km, but chances are, even if they had life on them, they wouldn't support human life without modification. The 12 Colonies System was designed for Rocketpunk.

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#14 2014-01-10 16:58:31

Quaoar
Member
Registered: 2013-12-13
Posts: 420

Re: Developing Saturn

Tom Kalbfus wrote:

What do you think of the fictional planet Polyphemus and satellite Pandora from the movie Avatar? How realistic is such a set up? http://james-camerons-avatar.wikia.com/wiki/Pandora

I've heard that gas giants are just about ruled out in the Alpha Centauri System, but in case there was one how realistic would that be? Polyphemus' radiation environment would probably be even more lethal than Jupiter as it sits right in the habitable zone Pandora has a gravity of about 0.8 of Earth.

http://james-camerons-avatar.wikia.com/wiki/Pandora


Avatar
Diameter     11447 km
Mass     0.72 Earths
Gravity     0.8 g
Atmospheric density     1.2 Earths
Surface pressure     0.9 atm


Very realistic: even the vortex is a phenomenon, due to interaction of ions current in the radiation belt with the magnetic field of the moon and the giant plantet, really observed between Juppiter and Io. On Pandora, the strong magnetic field of the vortex is the cause of superconductive levitation of unobteium rich rocks.
Polyphemus has a strong radiation belt like Juppiter but Pandora is protected by her own magnetic field and by her dense atmosphere, so life is possible.

Last edited by Quaoar (2014-01-10 17:00:01)

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#15 2014-01-10 17:14:54

Quaoar
Member
Registered: 2013-12-13
Posts: 420

Re: Developing Saturn

JoshNH4H wrote:

If anything I would say the Jovian system is fairly amenable to this kind of inter"planetary" civilization, insofar as the bodies are fairly close to each other and don't have too high delta-Vs to get from one to the other.  There's also, ya know, four of them smile

If in the context of a story someone wanted to terraform the four moons you'd have a pretty good basis for a rocketpunk story.

A whoole terraformed moon will have insufficient insolation, but we can imagine paraterraformed Moons with a lot of big colonies under domes, with fusion powered artificial light. It may be intriguing to know if may be better building surface colony on the moons or using the moons as mines of raw matherial to build giant orbital space habitats: an habitat with 1 gee gravity may be best suited for humans, but in a future we can imagine radiation resistant GM people that not suffer of muscular atrophy and bone mass loss in microgravity and low gravit and can quickly adapt from 0 to 2.5 gee environments.

Last edited by Quaoar (2014-01-10 17:15:37)

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#16 2014-01-15 09:03:00

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Developing Saturn

I think the planet itself has the most potential for terraformability, it has the right gravity after all and its moons do not, at best the moons are resources for O'Neill space colonies. A Moon like Titan would be a water World if you could terraform it, or you could dispose of its water and terraform its core, but it would be a very small world. Saturn by contrast has 100 times Earth's surface of potential 1-g inhabitable areas. One could also go the cloud city route as in Venus.

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