[SPACE] Planets in a Binary Star System

[whswhs]

Originally Posted by JediKnight83

I have been trying to put together a binary star system and there are a few things I want to know that I cannot find in the book. First, how does the forbidden zone of one star effect the forbidden zone of another star? Does the luminosity of the second star effect the system? And, if two stars are really close, can and will planets form around both of them and how would that work?

All of that is in the book, actually, if you read the discussion of forbidden zones closely. Except for temperature and luminosity. There is no simple way to do this. But here's what I worked out:

For a planet of star A:

Figure its temperature based on its orbital distance from star A, and star A's luminosity

Figure its temperature separately based on the distance between stars A and B (which equals the planet's mean orbital distance from star B) and star B's luminosity

Raise both temperatures to the fourth power (that is, square them, and then square them again)

Add the resulting numbers

Take the fourth root (that is, take the square root, and take the square root again)

This will be the blackbody temperature of the planet based on the input from both stars. It won't be much different from that for star A alone, but a really cold planet of star A may get a noticeable boost from star B.

Bill Stoddard