Good Egg Galaxy
The Good Egg Galaxy is one of the first worlds in Super Mario Galaxy. Not much is known about this galaxy but it is known that both the Dino Piranha and King Kaliente will be fought here.
Planets
Pill Planet
The planet is shaped like a giant, transparent pill. It contains many obstacles and items, mainly Coins and Item Crystals.
Atop the towering planet is a Boost Star that Mario can break out of the Pill Planet's glassy surface with. It has been shown that Mario will have to walk on both the floor and ceiling to go through it.
Magma Planet
This is where the boss battle against King Kaliente takes place. It consists of a hot lava pool with a shiny tar-like ring of ground around it, and the rest of the planet is just simple hot rock. The planet is quite big compared to others like the Tropic Planet, since it needs to have a decently large size for the fight to be held. Underneath the Magma Planet is a rocky area with yellow rings on it like a target.
Yoshi Egg Planet
A very small planet. The planet resembles a Yoshi Egg, and was first seen in a video at GDC 2007. It is currently unknown if anything is inside the egg, or if it is just a reference to the Yoshi clan. There is a Luma moving on top of the egg, as well as a Goomba. It is found in the Good Egg Galaxy, and may be the "Main Planet" since it is, after all, an Egg Planet.
Geo Planet
The Geo Planet is a planet.. It is a small planet where the Dino Piranha boss is battled. The Geo Planet is made of gravel and rock with hints of grass sticking out, much like a simple ball of earth mixed up together. There are Item Crystals on it with a few Coins in them.
Boulder Planet
It is a double-sphere rocky planet, like two Asteroid Planets merged together. It only consists of about three large boulders that Mario must dodge, as seen in the screenshot. It was first seen in the Star World (Galaxy), but an copy of the planet (albeit in a different colour) was seen in the Good Egg Galaxy.
