ATTENTION!!! THIS WAS MEANT TO BE FOR SUPER MARIO GALAXY 2!!! PLEASE DON'T THUMBS ME DOWN THE ACCIDENTALLY CLICKING #1!!! :(

In every galaxy, there is a special coin called a Comet Medal. It is a white, octagonal with a yellow brim. In the middle, you are able to see a comet. If you get enough Comet Medals, Prankster Comets will start to appear. A Prankster Comet is an additional level for some galaxies. Comet Medals are placed in hard to get to areas on places where you need a Power-Up. There is a total of 49 Comet Medals, unfortunately, there is not a Prankster Comet for all levels.

Here is a chart of the Comet Medal locations:

World 1

Galaxy

Comet Medal Location

Sky Station Galaxy

High above the cylindrical planet with gray platforms rotating around it.

Yoshi Star Galaxy

On a small green hill in the area where the player first obtains Yoshi.

Spin-Dig Galaxy

Next to the right-most pillar on the Drill Zone Planet.

Fluffy Bluff Galaxy

Above a column of coins on the Pond Planet. Cloud Mario is needed, or a triple jump or back-flip and spin at the apex of the jump.

Flip-Swap Galaxy

On a blue platform near the end of the first area.

Rightside Down Galaxy

Between two Thwomps in an upside down section, just after the Incoming Chomps.

Bowser Jr.'s Fiery Flotilla

Above the Thwomp near the beginning of the stage.

World 2

Galaxy

Comet Medal Location

Puzzle Plank Galaxy

Off to the side of a wooden platform, just before two Grinders cut off a vertical wall, which creates an area that Mario must wall-kick up.

Hightail Falls Galaxy

Near the end of the level right after the Hungry Luma.

Boulder Bowl Galaxy

Right at the beginning of the level inside the purple crystal. Rock Mario is needed.

Cosmic Cove Galaxy

Inside a large shell-shaped structure underwater, near the button that freezes the entire area.

Wild Glide Galaxy

Obtained after going through the five gates.

Honeybloom Galaxy

Between two Choppahs.

Bowser's Lava Lair

Reached by wall-jumping off a Whomp.

World 3

Galaxy

Comet Medal Location

Tall Trunk Galaxy

On the Log Planet.

Cloudy Court Galaxy

Near the end of the level inside the crushing wall.

Haunty Halls Galaxy

Over a large gap, just after a green pipe.

Freezy Flake Galaxy

Hidden beneath some Brick Block-shaped snow.

Rolling Masterpiece Galaxy

Near the end on a platform about to be cut by Grinders.

Beat Block Galaxy

Near the beginning on top of an orange Beat Block.

Bowser Jr.'s Fearsome Fleet

On the Airship with the Hammer Bros, just before Mario...