Planet

A planet is any celestial body that orbits a star in a star system. On multiple Poptropica islands  and mini-islands, you will travel to different planets.

Known Planets

 * Planet Poptropica
 * Jungle Planet
 * Fire Planet
 * Ice Planet
 * E. Vile's Planet

Role on Astro-Knights Island
Throughout the quest of Astro-Knights Island, you will travel to different planets and battle various bosses. The Three islands that you travel to are the Jungle Planet, Fire Planet, and Ice Planet. In addition, Planet Poptropica is where all of the Poptropica islands are located, and you must land back there in order to travel to different islands.

Role on Legendary Swords
At the beginning of the Legendary Swords quest, you will be shown a cutscene in which you fly in a rocket from Planet Poptropica to E. Vile's Planet. E. Vile's Planet is where the main quest of Legendary Swords takes place.

Trivia

 * Planet Poptropica looks like and is probably based off of Earth.