Class L Planet

Do you have thick skin? Enjoy a challenge? Maybe Class L is for you. These are planets that are considered only marginally habitable. They are suitable for human colonization, but native life is usually lived to vegetation. About the same size and age as Class M planets and also located in the ecosphere, Class L worlds have barren, rocky surfaces with very little water. The atmosphere of a Class L world is comprised mainly of Oxygen, Argon and Carbon Dioxide. Some surface views of Class L planets have been seen onscreen, with an environment reminiscent of the High Sierra Nevada mountains in the western United States during winter.

Examples of Class L Planets

Indri VIII

The planet Indri VIII is the world whose biosphere was destroyed by the Klingons in the TNG episode “The Chase.”

Many other Class L worlds have been visited in Star Trek episodes but were not given names. You’ll find Class L planets in “The Ascent” (DS9), “The Sound of Her Voice” (DS9), “The 37’s” (VOY), “Muse” (VOY), “Renaissance Man” (VOY), and “Bounty” (ENT).

Class N Planet

Some like it hot, and those people love Class N. Located in the ecosphere and the same size and age as Class M planets, this class has been overrun by a dense carbon dioxide atmosphere that creates a greenhouse effect making the surface temperature inhospitable to life as we know it.

Example of a Class N Planets

A Class N planet has been referenced onscreen in the TNG episode “Night Terrors” though not given a name.

Class O Planet

A favorite amongst fans of water sports, Class O planets are roughly the same size and age as Class M but have a surface that is more than 80% covered with water. Located in a star system’s ecosphere, Class O worlds have the same Nitrogen-Oxygen atmosphere as a Class M world and are well-suited to support life. You may find aquatic vegetation, marine life, and even humanoids on these planets. Star Charts refers to these bodies as “pelagic,” or relating to the open sea.

Examples of a Class O Planets

Argo
Monea

Argo is the homeworld of the Aquans and was visited by the U.S.S. Enterprise in The Animated Series episode “The Ambergris Element,” while Monea is the ocean-covered planet in the Voyager episode “Thirty Days.” Tom Paris’s actions on Monea resulted in his demotion to Ensign.

Class P Planet

What happens when you take a Class O planet and stick it into a giant freezer? You get a Class P planet. Located in a star system’s ecosphere, these worlds have the same Nitrogen-Oxygen atmosphere as a Class O world but instead of being having a surface that is more than 80% covered with water, these planets are more than 80% covered by ice. Despite the cold, they can host a variety of life including hardy vegetation, animals adapted to the chilly environment, and even humanoids (thick-skinned no doubt.) Star Charts refers to these bodies as “glaciated.”

Examples of Class P Planets

Breen
Exo III
Europa (Jovian moon)

Another Class P planet that has been seen in Star Trek is the ice planet on which Voyager crashed in the episode “Timeless.”