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 observatory, and guides to Mario showing him a map of the space. 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 its age and because he's usually hanging around with her.

Trivia

 * Polari's name comes from the star "Polaris", or the North Star.