Complex sentence: In the fictional "Star Trek" universe, the Planet Classification System is a system developed by the Federation to categorize planets by many factors, such as atmospheric composition, age, surface temperature, size, and presence of life.
Split into simpler sentences: In the fictional Star Trek universe the Planet Classification System is a system developed by the Federation to classify planets. Planets are categorize on many factors like atmospheric composition, age, surface temperature, size, and presence of life.