Power Stars are items in Super Mario Galaxy. They are the most important stars and items in the game. There are a total of 121 Power Stars for both Mario and Luigi (both = 242 Power Stars). There are 4 types of Power Stars. The regular Power Stars (as seen in picture) are the most common of all. The second kind are the Green Power Stars. They are like Power Stars only green. There are 3 needed to unlock the Green Launch Star in the Comet Observatory that leads to the Trial Galaxies. The third is the Red Power Star that is red in color. Only one appears in the game. That one Red Power Star appears in the "Gateways Purple Coins" mission. Last are the 7 Grand Stars. The are larger than all the other Power Stars. The first appears in Gateway Galaxy. It is the first Power Star you collect.