Callisto (Jupiter IV)
Callisto is a moon of the planet Jupiter. It is the third-largest moon in the solar system, and the second largest satellite of Jupiter, about the same size as the planet Mercury.
Callisto possesses two quite distinct intelligent species. One type is humanoid, though smaller and thinner than humans, and with four arms. These Callistans have scarlet eyes, white fur, and scarlet feather-like antennae atop their heads. They possess psionic abilities that they can project through the music of specially designed instruments (The Citadel of Lost Ships).
The other intelligent species, the cat-men, descend from a feline ancestor. In shape they closely resemble humans, and except for their tails, clawed feet, and a mane of fur across their shoulders and down their backs to the tail could pass for human. They are, however, forbidden to mix with humans and will retaliate against any member of their species who does so. Their most significant weakness is the propensity to become addicted to coffee (The Halfling).
Read more about this topic: Jupiter In The Fiction Of Leigh Brackett