What is it that triggers civilian expansion and growth outside of the home system?
I've surveyed 8 systems outside of my home system, one of which is exceptionally mineral rich. Now, I've created a few colonies on these wealthy worlds and have about 2,000,000 population on one of them. However, there are still no civilian vessels in the system and no mining operations other than my own.
What is the trick to getting them to start populating other systems?