Season

Earth had four seasons: spring, summer, autumn and winter. (TV: The Mutants)

Ribos had two seasons, each running for approximately thirty-two Levithian years: Icetime and Suntime. This was due to Ribos having an extremely elliptical orbit around its sun. The Ribosians believed that the seasons were respectively caused by the Ice Gods and the Sun Gods, who they thought were fighting over Ribos. (TV: The Ribos Operation)