So in all my games to date, I never put a colony on a Comet. Sure, CMCs have setup on comets before but I never had a reason till this game - large relatively slow comet with a population cap of 7 million and an absolutely large amount of Sorium, Vendarite, and Mercassium at .8 accessibility and higher. Within two years, I built up a colony of 6 million, mines and mass drivers, and a small naval station with fighters, AWACS, and a search and rescue LAC. All good! Until all of a sudden I started getting unrest due to overpopulation. I was like, ‘Wait a minute!?!?’ And then discovered that as a comet moved further away from the sun, things get colder and habitability drops precipitously. I suppose I could pump in a bunch more LG infrastructure (at huge cost) and flag the body as not a source/destination for colonist but I ended up pulling the colonists and the Naval Station and replacing with automated mines. Lesson learned.