A planet's designation determines what it does within an empire. The main way it does this is by defining the planet's primary structure. Planets can only export resources produced by their primary structure. If the primary structure produces units, the planet cannot export any resource. Some designations have primary structures that do not produce anything at all; these structures instead grant a special effect, like increasing the tech level of other planets.
Planets are typically manually designated by the player, by pressing the “Designate” button. Designation is instantaneous, but it takes a couple of watches for the new primary structure to reach full production. Designating a planet temporarily reduces efficiency. Planets can only be given designations that are allowed by their current tech level and deposits.
Converts labor into tech levels that can be imported by other planets nearby using normal trade routes. TL 5 or higher. The planet's TL will increase to match the TL of the imperial capital if it is lower. Primary structure is foundation. This can be more efficient overall than building tech programs. Foundations cannot uplift other planets to TLs higher than that of the imperial capital.
Allows the player to designate and issue orders to planets within a 250LY radius. The imperial capital is the first planet that the player starts with and cannot be manually re-designated. Primary structure and other effects depend on imperial doctrine. If the imperial capital is conquered, a sector capital will become the new imperial capital. If there is no appropriate sector capital, the entire empire will be destroyed.
Allows the player to designate and issue orders to planets within a 250LY radius (takes 24 hours after designation). TL 5 or higher. Must be >250 LY from the imperial capital or another sector capital and is the only designation that can be given to such planets. Primary structure and other effects depend on imperial doctrine. Vulnerable to secession. If a sector capital is conquered, some planets within 250 LY will randomly defect.
Planet can import and export all resources, allowing it to consolidate and redistribute resources among many planets. TL 5 or higher. Primary structure is starport. Also contains the militia base structure which builds basic infantry. Surplus labor is assigned to the starport, which wastes it; it is better to assign labor to planetary defenses or the militia base.