Would that work? I'm no physicist so it seemed plausible to me, but I've asked physics students and they seemed to doubt it would be possible.
Even if the star system itself is possible, the sheer number of terraform-able planets is outrageously convenient. For that matter, I'm still curious how the Alliance was able to make the "atmo and gravity close to Earth-that-was" or whatever Zoe said. I mean, altering the atmosphere is one thing, but playing around with the mass or gravity of a planet seems light years ahead of what we saw of Alliance technology. It makes absolutely no sense.