Tom Kalbfus
Mongoose
Here is the Helios Beta mini system

I should also make them green and not blue. The color scheme for solid planets is thus, Red indicates it is in the inner zone, green indicates its in the habitable zone, and blue indicates its in the outer zone. The circles in the Caprica/Gemenon map indicate distance from Caprica more that anything else, not all those circles represent viable orbits, and certainly none are around Gemenon, though they should be. Generally all orbits more that a third away from either planet or less that 3 times away from both planets are unstable, though you can fly through them in a spaceship, you can't orbit at those distances and expect your orbit to be stable without active correction.Tenacious-Techhunter said:The Caprica-Gemenon system should be redone so that they orbit around the Barycenter.
That is one unEarthlike aspect to them. I'm thinking of having native humans there, basically Barbarians and savages besides the pirates and more recent colonists.Tenacious-Techhunter said:Gemenon is 1.709421123428962 times larger than our Moon appears in our sky; somewhere between an additional 2/3rds and an additional 3/4ths.
The tides on Gemenon and Caprica have 20 times the pull the Moon does; they are more or less 80 times more massive than the Moon, at twice the distance, which divides the pull of the mass by 4. No ocean-front property without massive seawalls.
On the other hand, “King Kamehameha likey!”.
Tenacious-Techhunter said:My gut instincts tell me those 3 planets orbiting so close together can’t be stable... see Orbital Resonance on Wikipedia. Planets in that sort of proximity need orbits further apart in order to have the necessary resonance to be stable, I think.
Where’s that Barycentric Caprica & Gemenon?
Depends on by how much the middle orbit is inclined to the outside and inside orbit. What happens if all three orbits are on the same orbital plane is that the inner planets slowly over take the outer planets in their orbits.Tenacious-Techhunter said:A skew like that doesn’t invalidate the math, but it does alter it... Can’t say by how much, though.
Where’s that Barycentric Caprica and Gemenon?
How long do they have to be on track? Lets take the simple case, lets suppose there was a planetary system where one planet orbited at a 90 degree angle from another planet that was a little further out. How often does this planet come close enough to the second planet to significantly influence its orbit? How often does this planet cross the orbital plane of the next planet? About twice per orbital period. Now lets suppose that planet was orbiting with a 0 degree inclination at the same radii, when the 90 degree planet crosses the orbital plane of the next planet further out, it is traveling at a much greater relative velocity past the next further out planet, that would the planet at that same radius if it was orbiting in the same orbital plane, because it would be traveling only a little bit faster than the further out planet, it would pass that planet very slowly and would gravitationally interact with it for a long period of time, plenty of time to influence its orbit.Tenacious-Techhunter said:If you’re the one picking the orbit radii, you need to work a bit harder on your orbital resonances; they’re just about the only thing that is going to keep your planets on track.
There are some pros and cons to that. What makes it so interesting is this system they created, otherwise it would just be another ho hum science fiction setting where you need an FTL drive to reach the various parts, but the interesting thing about the Cyrannus system is you don't need a jump drive to get from one planet to another. The furthest parts of this system are separated by 0.16 light years, this is about two "light months" Caprica and Gemenon can have near real time communication, it is 493,000 miles of separation between the two worlds, light travels at 186,282 miles per second, that makes them 2.65 light seconds apart, so radio communication would have been established early on, most commerce would have been on a slower than light basis, with an economic incentive towards faster than light travel. It is possible within the old physics to send a rocket ship from the system of Helios Alpha to Helios Delta in less than a year using the classic travel formulas for slower than light travel, the speed of light limitation only pinches a little. With commerce between all twelve worlds, and money to make, people would have economic incentive to figure out faster ways to travel, as commerce would have already existed on a slower than light basis.Rikki Tikki Traveller said:When I played with putting the twelve colonies into a Traveller setting, rather than try to shove them all into a single star system, I put them in adjacent hexes on a subsector map.
They also put God into the picture, which most science fiction writers don't do for fear of offending certain readers and viewers. They literally used "Deus ex Machina" It would be more ho hum if they stuck to the usual Star Trek stuff. BSG also had a very unique tech level, they were only futuristic in spaceships and the technology needed to make Cylons, everything else was our tech level. The pirates in my example for instance, would be very unimpressed with the Ancient Caprican slug thrower firearms, if they could build a Cylon, they would arm it with lasers and plasma weapons, not these slug throwers seen on the show which would quickly use up ammunition.12 worlds with ATM 5, 6, or 8 all within Jump 1 of each other would be a tasty find and quickly be settled by anyone. Simple J-1 connecting a "cluster" of habitable worlds.
When using Traveller rules, that is probably the easiest way to do it. I know the "official" material puts all 12 habitable planets within one star system, but that is what happens when WRITERS try to do SCIENCE without asking anyone.
Why do you suppose Mars has the atmosphere its got, and not the one that we once imagined it had?As Matt suggested, a Thicker Atmosphere (ATM 8 or 9) would allow a world just outside the habitable zone to possibly have breathable/habitable surface, although it is still likely to be a bit cold. Greenhouse gasses in small (but measurable) concentrations (probably Taint the Atmosphere) would also allow it to be habitable, although probably still COLD.
Clouds and lots of water might allow a world just inside the habitable zone to still be habitable (probably HOT). Should be able to reasonably get 3 habitable planets around a G or F star. Interestingly, if you go with a red dwarf star (M class) you can likely get MORE planets in the habitable zone, like some real star systems we have found. Of course these planets would be tidally locked to their star, so not TOTALLY habitable...
Tom Kalbfus said:How long do they have to be on track? Lets take the simple case, lets suppose there was a planetary system where one planet orbited at a 90 degree angle from another planet that was a little further out. How often does this planet come close enough to the second planet to significantly influence its orbit? How often does this planet cross the orbital plane of the next planet? About twice per orbital period. Now lets suppose that planet was orbiting with a 0 degree inclination at the same radii, when the 90 degree planet crosses the orbital plane of the next planet further out, it is traveling at a much greater relative velocity past the next further out planet, that would the planet at that same radius if it was orbiting in the same orbital plane, because it would be traveling only a little bit faster than the further out planet, it would pass that planet very slowly and would gravitationally interact with it for a long period of time, plenty of time to influence its orbit.Tenacious-Techhunter said:If you’re the one picking the orbit radii, you need to work a bit harder on your orbital resonances; they’re just about the only thing that is going to keep your planets on track.
Tom Kalbfus said:Here are some ideas that weren't used. Suppose the planet orbited in the opposite direction from all the other planets in the system?
Tom Kalbfus said:Also have you ever considered the possibility that this system was not natural? It seems a very improbably arrangement to happen by chance.
Tom Kalbfus said:Take for example Caprica and Gemenon, both are each other's moon, yet they aren't tidally locked with each other as is our moon.
Tom Kalbfus said:Why do you suppose Mars has the atmosphere its got, and not the one that we once imagined it had?As Matt suggested, a Thicker Atmosphere (ATM 8 or 9) would allow a world just outside the habitable zone to possibly have breathable/habitable surface, although it is still likely to be a bit cold. Greenhouse gasses in small (but measurable) concentrations (probably Taint the Atmosphere) would also allow it to be habitable, although probably still COLD.
Mars is that way because it is small, has no magnetic field, and it is farther from the Sun. if Mars had a thicker atmosphere, it no longer does now, because it was lost into space. I think Mars can temporarily be made habitable if given an Earthlike atmosphere, such an atmosphere would have enough greenhouse effect to produce balmy tropical temperatures on its surface, but that atmosphere would eventually be lost into space for the same reason that its first early atmosphere was lost.
Tom Kalbfus said:One idea I have been toying with is to have red dwarfs orbiting a G-Type star, each one is a little brighter than the previous one orbiting closer to the star. A tidally locked world orbits each red dwarf, and the heat from each red dwarf carries over to the far side to make up for the lack of heat and light coming from the distant primary. I don't know any examples of red dwarfs orbiting near the habitable zones of primaries, but that doesn't mean their aren't any.
Well our Solar System is 5 billion years old, that is the planets of this system are 5 billion years old, What if the Cyrannus System was not 5 billion years old, what if it wasn't even 1 billion years old? If these Worlds are young enough, they might not have had time enough to become tidally locked. All 12 worlds support human life, they have wildlife that is compatible with humans, humans can eat them and they can eat humans. They have dogs and cats, they raise livestock, have chicken dinners, nothing alien about them or the animals they share their worlds with, what does that tell you? At the very least, all the ecologies on all the 12 colonies were planted there, a terraformed world is to that extent artificial, I don't think it was parallel evolution, I don't think it was chance that made these planets this way. I think if we could spin up our moon and give it a 24-hour rotation period, it would not slow down and become tidally locked after a few days, the angular momentum of the Moon is very significant. I think in similar terms Caprica and Gemenon could easily stay spinning for hundreds of thousands of years, the slow down in rotation would be greater than Earth's slowdown due to Lunar tides, maybe 20 times greater, so what does that mean? Does it mean that instead of taking 1 billion years to completely slowdown and tidally lock it instead takes 50 million years to do the same? Over the span of 50 million years 150, thousand years isn't that significant. Lets say Caprica was arranged to have a 24-hour day, and it would be expected to become tidally locked with its twin planet in 50 million years, so lets do the math. 24 hours means Caprica turns 15 degrees per hour relative to its twin, and if it became tidally locked with it in 50 million years, what happens after only 150,000 years? 150,000/50,000,000 = 0.003, and 0.003 * 15 degrees is 0.045 degrees, subtract this from 15 degrees per hour and we get 14.955 degrees per hour and if we multiply this by 24 we get a 358.92 degree rotation every 24 hours. divide 360 by this number and we get 1.003 days or a day that lasts 24.072 hours long, for game purposes that is still a 24 hour day!Tenacious-Techhunter said:Tom Kalbfus said:How long do they have to be on track? Lets take the simple case, lets suppose there was a planetary system where one planet orbited at a 90 degree angle from another planet that was a little further out. How often does this planet come close enough to the second planet to significantly influence its orbit? How often does this planet cross the orbital plane of the next planet? About twice per orbital period. Now lets suppose that planet was orbiting with a 0 degree inclination at the same radii, when the 90 degree planet crosses the orbital plane of the next planet further out, it is traveling at a much greater relative velocity past the next further out planet, that would the planet at that same radius if it was orbiting in the same orbital plane, because it would be traveling only a little bit faster than the further out planet, it would pass that planet very slowly and would gravitationally interact with it for a long period of time, plenty of time to influence its orbit.Tenacious-Techhunter said:If you’re the one picking the orbit radii, you need to work a bit harder on your orbital resonances; they’re just about the only thing that is going to keep your planets on track.
The problem with this line of thinking is that you are assuming the planets spawned into existence perfectly formed, as opposed to developing over time; the correct answer to this question is, “Long enough for the system to have formed from a dust cloud into its current state.”; which means it had to be pretty damn stable.
Tom Kalbfus said:Here are some ideas that weren't used. Suppose the planet orbited in the opposite direction from all the other planets in the system?
Not impossible, but you still have to account for its gravitational effects.
Tom Kalbfus said:Also have you ever considered the possibility that this system was not natural? It seems a very improbably arrangement to happen by chance.
This really isn’t part of any Battlestar Galactica canon that I’m aware of. It’s fine if you want to go this route, but if you’re going to do that, you might as well go whole-hog with it, and put all the planets on the same orbit, with some phase difference between them. Also, you’re going to have to leave some blatantly obvious equipment related to moving planets around. Frankly, if you can move planets into whatever orbit you want, you can make them all the same size within a reasonable enough tolerance to make them stable. So I’m not really buying the “artificially made” argument. I think you’re better off doing the orbital resonance work.
Tom Kalbfus said:Take for example Caprica and Gemenon, both are each other's moon, yet they aren't tidally locked with each other as is our moon.
Considering that they are each experiencing 20 times the force of the Moon on each other, it’s pretty laughable that they wouldn’t be tidally locked.
If we moved Jupiter into orbit 4 and made Mars its satellite, then Mars would indeed have volcanism due to tidal heating, we set up some orbital resonnances and Mars would be constantly changing its distance from Jupiter and it would have volcanism like Io, if we give it enough volcanism, it would be belching out gases and recycling its crust the way Earth does. We would have to supply just the right amount of tidal forces to make up for the lack due to insufficient radiactive decay in Mars' crust, we don't want hyper-vulcanism the way Io does.phavoc said:Mars is a bit of a dead world today, and without the mass to hold in the atmosphere it is indeed slowly losing it. However, if Mars had active vulcanism today (and Olympus Mons was active), it could be adding more gases to the atmosphere. Whether or not it would be sufficient to offset the losses is unknown.
Tom Kalbfus said:If we moved Jupiter into orbit 4 and made Mars its satellite, then Mars would indeed have volcanism due to tidal heating, we set up some orbital resonnances and Mars would be constantly changing its distance from Jupiter and it would have volcanism like Io, if we give it enough volcanism, it would be belching out gases and recycling its crust the way Earth does. We would have to supply just the right amount of tidal forces to make up for the lack due to insufficient radiactive decay in Mars' crust, we don't want hyper-vulcanism the way Io does.phavoc said:Mars is a bit of a dead world today, and without the mass to hold in the atmosphere it is indeed slowly losing it. However, if Mars had active vulcanism today (and Olympus Mons was active), it could be adding more gases to the atmosphere. Whether or not it would be sufficient to offset the losses is unknown.