These galactic constructions are included in SE4 as homages to various sci-fi sources. For game purposes, they are big planets that you create around a star late in the game. First, you must research Stellar Manipulation, at least to level 5 for ringworlds, or all the way to level 8 for sphereworlds. You also have to research Base Construction to Level 3 to get starbases. And since this is all big and expensive, you might as well take spaceyard tech to level 3 as well, but this isn’t required. Next you must create, in the same sector as a star, the activator component, and the correct amount of plating and high-tension cables components. Only one of each will fit on each starbase, which will also need Command and Control components. You’ll probably need a mobile spaceyard ship to start the building process, but it can build base spaceyards can build other shipyards, until you have enough to build all the starbases. Once everything is built, you can activate the activator component, and