Power Stars are collectible items that can grant Mario access to more levels in-game (like Flagpoles from the original Super Mario Bros. and the New Super Mario Bros. series); however, regular Super Stars only give limited invincibility. In Super Mario 64, Super Mario Galaxy, and Super Mario Galaxy 2 when the star for any given level has been collected, playing the level again will turn the Star into a translucent version of itself (similar to how Star Coins work). This Star can be collected, but it will not add to the player's total Star count. In all, there are 634 Power Stars in these three games combined.~Mario Wiki

3D model ripped by alecpike