[Lupusman]

Looks like you can make a terrafrom ship. It would be planet specific also.
Just make a ship component using the ability line 'Planet - Change Atmospere'
Put in whatever amount of turns you think appropriate for it to change over.

You would probably need a colony first though as it looks like it changes the atmosphere to the predominant race that is on the planet.

I wonder if more ships over the planet would make it work faster?