With billions of worlds throughout the Milky Way and an estimated hundreds of thousands throughout the Kelveros Cluster, a massive variety of worlds are believed to exist. A universal method of classifying these worlds was established in 480 ERB, following the first massive exploration effort by Humanity.
Desert[]
Class A[]
Class A Desert worlds are worlds that have an atmosphere, but possess harsh climates, temperature fluctuations, and have little water throughout the world.
Class S[]
Class S worlds are barren worlds, lacking an atmosphere, any form of liquid, and usually are battered with impact craters. Worlds such as Mercury, Karravesk, and many others are considerd class S worlds. Class S desert worlds are the most common type of planet.
Continental[]
Class E[]
Class E Continental worlds are worlds with cool to warm climates, massive oceans and landmasses, and occasionally, life. Worlds such as Earth, Wintermoor, Prima Asinica, Neostra, and other worlds colonized by humanity are considered Class E Continental worlds.
Class O[]
Class O Continental worlds are a relatively rare form of world, known for having their entire surface covered in either a liquid ocean, or thick ice sheets. Their description as "Continental" is occasionally contested, arguing the possibility of these worlds lacking any atmosphere, however no changes have been made.
Class T[]
Class T Continental worlds are worlds very similar to Class E worlds, however instead of possessing oceans and atmospheres with massive quantities of water, instead have Methane, CO2, or another liquid. Typically these worlds are far too cold for colonization by Humanity. Titan is considered a Class T Continental world.
Gaseous[]
Class G[]
Class G Gaseous worlds are worlds such as Jupiter, Saturn, and Jericho. These are typically the largest type of planet, as the next largest class of structure is a brown dwarf star.
Class I[]
Class I worlds are ice giant worlds, such as Neptune, Uranus, and Kaicili. These are typically cool, distant worlds, however rarely they can be found near their host star.
Other[]
Class TE[]
Class TE worlds are worlds that naturally existed as either a Class A, a Class S, or a Class T world, which through massive amounts of terraforming have been converted into Class E continental worlds. Mars and Venus are examples of Class TE worlds.
Class TD[]
Class TD worlds are worlds which might have been Class E or Class T worlds, which through Meteor impacts, a massive nuclear assault, glassing, or any other cataclysmic event, converts a Continental world into either a Class A or Class S Desert world. The only example known to Humanity of a Class TD world is Minerva, which was completely destroyed in the Human-Segaruu War.