During play there seems to be a bug that stops anyone from colonizing most planets as both the ai that i was playing against had colony ships at the planets yet no one had colonized it and i was unable to due to colony ships dropping the order as soon as they come into sight of the planet. Although some planets still seem colonisable as i was able to colonize 2 out of about 10 worlds that were shown as colonizable
http://i.imgur.com/esrFWts.jpg
