Whoops, looks like I made another newbie mistake. I had colonised a breathable planet in my second system. Could build 10 facilities, built 4 research centers and a space yard. NOW I find out that spaceports are needed not only for resources but also for research points
So that probably puts me behind you guys on the research curve.
In an attempt to reduce the huge maintenance cost on the fleet I am now constructing (4 colonizers and supporting escorts) I have sent out two destroyers with remote mining equipment to some high-mineral planets. They're nice huge gas planets, but I don't think I'll get gas colonisation anytime soon so too bad for the depletion of minerals I'm causing now on those planets.