Polari

Polari is an elderly dark brown Luma who appears in Super Mario Galaxy. Polari is the one of the oldest Lumas and is Rosalina's most trusted adviser. He knows all about the Comet Observatory, and serves as a guide to Mario by showing him a map of the galaxies visible from it. Polari is Toadsworth's galactic counterpart, just as Rosalina is Princess Peach's counterpart. Like Toadsworth, he is very protective of Rosalina and is eldest of his kind. It is likely that his brown color is a reference to brown dwarfs, stars that are the dying remnants of stars that were not large enough to go nova. Polari might be the first Luma Rosalina met, because of his age and because he is usually seen by her side.

Trivia

 * Polari's name comes from the star "Polaris", or the North Star.
 * Polari is like "Rosalina's Toadsworth" since Polari is an advisor and watches over her.
 * In Mario Kart Wii, Polari does not appear along side Rosalina. Instead, it is a regular unnamed Yellow Luma.