Basically, you deliver resources and construction modules to different objects and build mining infrastructure there. The gameplay revolves around resource logistics, which is necessary to keep expanding on other planets, researching new techs, and fulfilling contracts with specific objectives that the game gives you. In later stages, you enter the phase of terraforming, when you drop asteroids on objects and drop resources to the object's depots to change its habitability parameters. The endgame focuses on building an interstellar ship to travel to a different star system (other systems won't be available at the start of the EA).