In planetary classification, a class C reducing planet is a type of planet. As the name describes, the planet is characterized by the ongoing reduction of gases in a typically dense atmosphere. In particular among iron-silicate planets, the class C worlds of this type are posessed of high levels of trapped heat energy. Venus is an example of a class C reducing-atmosphere world. (ST references: Star Trek Maps, The Worlds of the Federation) This classification should not be confused with the class C geoinactive planet described in ST reference: Star Charts.