There's the main map area where everyone starts (4 factions in 2 pairs with each pair having adjacent homeworlds), off to one side is the pirate base, off to the other side is the wormhole.
Beyond the wormhole there is the star, and there are 3 chains each of 3 uncolonizable gravity wells that end in dead asteroids. To find the "remains of ancient starships" you need to colonize the dead asteroids and upgrade the Explore Planet development twice. It will give your faction an artifact bonus.
There are no actual ancient starships involved.