What planets are possible to colonize?

Often it’s worth waiting a decade or so to gain access to a species that is better adapted to the planet in question or access better habitability bonuses, but you want to capture every planet at some point. If everything else is the same, a new colony near your borders is preferable to a more distant colony for the following reasons. The reason why you shouldn’t colonize all the planets right away is that they need time to pay off because pops need to grow a while for the planet to be profitable. In general, low-hab worlds take longer to be profitable because you earn less from jobs and have a higher upkeep, making the profitable point higher and you’re also slowing down. The colonized planets offer you the opportunity to expand individual sectors, which affects the process of obtaining individual resources.

Can you terraform a planet after Stellaris colonization?

It is also possible to terraform habitable worlds, although this is a costly and time-consuming process. Terraforming is the process of changing a planet’s planetary classification to make it more habitable for the Empire’s species. I think a lot of people know the idea of terraforming from science fiction and were perhaps hoping that it could be possible on Mars. Underlying technologies require significant societal research to unlock them, and any terraforming project requires significant energy and time investment

Recent missions to Mars have shown that most of the planet’s ancient, potentially habitable atmosphere is caused by solar wind and radiation in the space has been lost.