In the 2009 film Avatar, what fictional planet does Pandora orbit?

In the 2009 film Avatar, Pandora orbits the fictional gas giant Polyphemus.

James Cameron’s Avatar places its main setting on Pandora, a moon in the Alpha Centauri star system. Polyphemus is the large planet around which Pandora revolves, giving the fictional world a moon-and-gas-giant arrangement rather than making Pandora a standalone planet.

This detail is part of the film’s scientific-style worldbuilding. Pandora has Earth-like gravity and atmosphere in some respects, but humans still require breathing equipment because its air is not safe for them. The moon also has a strong biological network connecting its living systems.

Polyphemus is named after the Cyclops in Greek mythology, while Pandora takes its name from another Greek mythological figure. The two names therefore reinforce the film’s use of classical mythology in its fictional astronomy.