Green Star

Green Power Stars are green-colored Power Stars that can be found in Super Mario Galaxy and Super Mario Galaxy 2. Only three Green Power Stars are known to exist in Super Mario Galaxy, all of which are hidden away in certain galaxies. Collecting all three of them will grant Mario access to the three Trial Galaxies; the Rolling Gizmo Galaxy, the Loopdeeswoop Galaxy, and the Bubble Blast Galaxy. Green Lumas will grow up to turn into Green Power Stars. In Super Mario Galaxy 2, however, there are a total of 120 Green Power Stars to be found. These are only available once the player collects 120 regular power stars. Each Galaxy has the same number of Green Power Stars as regular power stars, i.e. if a Galaxy has 2 power stars, it will also have 2 green power stars.

Super Mario Galaxy

 * Battlerock Galaxy, Luigi under the Saucer: Saving Luigi under the 1st Power Star.
 * Dusty Dune Galaxy, Treasure of the Pyramid: Collecting 5 Silver Stars in the Pyramid Planet.
 * Buoy Base Galaxy, The Secret of Buoy Base: Under the Buoy Base sealed in a cage.

Trivia

 * Even though only three Green Power Stars are recovered in the game, a total of seven Green Lumas can be found on the Comet Observatory and the Planet of Trials.
 * Green Lumas grow up to become Green Power Stars, according to Rosalina.