The Gateway Galaxy is a galaxy in Super Mario Galaxy. Mario ends up here after being flung from the airborne Princess Peach's Castle with a cutscene starting when Mario wakes up, to find the Luma that rescued him. You'll be able to find two stars here, with the first one being near the very beginning and the second being accessible a lot later in the game when the player unlocks the Garden, the last dome in the game, by beating Bowser Jr's Lava Reactor. The first star is always the first star in the game and introduces Rosalina here. Mario will learn how to star spin to break open crystals, dizzy enemies, and use items to his advantage. It is here that Rosalina lives peacefully with the Lumas.