IPA: /ˌplænɪtəˈlɒdʒɪkəl/
KK: /ˌplænɪtəˈlɒdʒɪkəl/
Relating to the scientific study of planets, including their formation, structure, and processes.
The planetological research conducted by the team provided new insights into the formation of our solar system.
Planetological → It is formed from "planet" (from Greek "planetes", meaning wanderer) and "-logical" (from Greek "logikos", meaning pertaining to reason or study). The word refers to the study or reasoning related to planets.
Think of 'planetes' meaning 'wanderer' to remember that 'planetological' relates to the study of wandering celestial bodies.