[Space] Multiple/Lots of Stars in one system
 

I posted about this system before, but now I'm having trouble with a different part of it.

When dealing with lots of star how do you deal with Forbidden Zones? The Primary (1) has two distant companions (2 and 3) which in turn have their own distant companions (4 and 5) and star number 5 has made it's roll to have it's own companion (whose details I haven't really started working out yet and the system way still grow bigger)

So for Star 1 do I simply use the closest of it's companions (2) when determining the Forbidden Zone or do I have to worry about how close their companions could come to 1 at closest approach?

Re: [Space] Multiple/Lots of Stars in one system
 

[EDIT: This is for habitable zones, not forbidden zones. Don't post under the influence of hypoxia, kids!]

You can generally ignore distant companions. If they are close companions, multiply individual zone sizes by this chart:

If the planet is inside the overlapping multiplied zones, you are good. If the planet is mostly inside the zones, you have a situation where life has to hide or hibernate part of the time.

Re: [Space] Multiple/Lots of Stars in one system
 

I'm not sure that should be possible. Per the rules on page 105, a subcompanion is at a -6 penalty to its orbital separation roll, and as the maximum result on 3d6-6 is 12, the farthest a subcompanion can be is Wide. Since only Distant stars are eligible for the companion roll, a subcompanion may not have a subsubcompanion. The modifiers listed under the "Modifiers" heading are for companions, while the companion star of a compaion star is described as a subcompanion, so I don't think they apply here.

Per the rules on page 107, the outer limit is either M*40 or one-third the closest separation of the closest companion, whichever is smaller.

There is a mention made of planets orbiting a binary pair, but there's no solid guidance on that and it gets quite complex as more stars get involved.

I'm not quite clear on what this is for. Would you be multiplying the inner and outer limits for the stars by these? And this is for multiple stars orbiting very closely together? Also, what is the rationale behind taking the square root of the numbers? Forgive me if I'm missing something obvious.

Re: [Space] Multiple/Lots of Stars in one system
 

Well so far all of the stars are officially distant companions of whatever other star they orbit, but they can come mighty close to each other at times. The different between Component 2's Maximum Separation and Component 3's Minimum Separation is currently a mere 95 AU, which is closer then either of their own distant companions come by a factor of more then 2

Re: [Space] Multiple/Lots of Stars in one system
 

x2 as far as away means 1/4 of the warmth is given. If you can list the system's parameters, someone here can give you a more exact answer.

Re: [Space] Multiple/Lots of Stars in one system
 

Yes, you multiply the inner and outer limits by the multiplier given, so that you get larger but hopefully overlaping zones.

The square roots are due to the inverse square law for radiant energy intensity. For instance, if there were two suns just alike right next to each other, there would be twice as much radiant energy in their solar system as in a single-sun solar system.

That means the borders of the habitable zone would be 1.4 times farther from the two suns, because 1.4*1.4~=2 for twice as many suns making it twice as hot at the single radius. Also, 1/1.4 * 1/1.4 ~= 1/2 half as hot for being 1.4 times as far away.

Now if you combine both situations, 1/2 as hot for distance and 2 times as hot for multiple suns, 1/2 * 2 = 1, so that with two suns, you have the same temperature range at distances 1.4 times as far away.

Re: [Space] Multiple/Lots of Stars in one system
 

95 AU is more than far enough away to make all planet-forming concerns irrelevant. That's 3x farther out than Neptune.

Re: [Space] Multiple/Lots of Stars in one system
 

No, he's talking about habitable zones, for some reason.

As for inner and outer limits, the only thing to need to worry about is the star that comes closest. Distant companions are almost never an issue.

Re: [Space] Multiple/Lots of Stars in one system
 

Depends on the mass of the star and the whim of the random number gods.

A sun mass star has an outer limit of 40 AUs, which would be in a forbidden zone of a star with a periapsis of 120 AU or less. A bit different "rolls" might have put Neptune further out, or squeezed the gas giants' orbits together enough to fit another one in.

Re: [Space] Multiple/Lots of Stars in one system
 

This is only true if the star's outer limit is about 32 AU, which corresponds to a .8 solar mass star. For a 2.0 solar mass star, the outer limit is 80 AU, and a star has to stay outside 240 AU to have no effect.

Okay, so this only refers to the zones for the planetary temperature, and has nothing to do with the valid orbital positions for planets?