I once read that it would be difficult for a binary sun to have planets. The complex gravitation would pull the planet apart or eventually bring it so close to one or another of the suns that it would boil away any water. This has recently been shown not to be the case.
Many binary systems are far enough apart – much further than Pluto from the sun – so that planets can easily orbit one or the other sun without ever getting caught up in the other sun’s gravity. In other systems, the suns are close enough together that the physics makes them basically one star and a planet can orbit the pair without being pulled into the dangerous areas between the suns.
This is a relief and greatly increases the number of stars that are potential nurseries for intelligent life. A while ago, I tried my own variation on the famous Drake’s Equation that is used to estimate the probability of finding another intelligent species in space. I figure that there is at least one intelligent life form within 1000 light years of us right now. I excluded binary stars. By including binaries the number could be ten times that! By my poor math, the odds are 50/50 that there is an intelligent species right now within 100 light years of earth – that’s just a hop, skip and a jump away. Alien invaders could be on their way right now.
I don’t think I ever blogged those calculations, but I have no idea where I put them. I’ll search and if I find them I’ll make a page on CthreePO.com.