Planetary Classification

Planetary Classifications

Class C (Chthonian)

A Class E Planet

Class H (Harsh)

Class H worlds are generally habitable, at least in part, but have reduced resources or favorable elements compared to a Class M world. Harsh planets often lack water, have very thin atmospheres, extremely turbulent and destructive weather, or else have wild temperature swings. Life can and does spring from such worlds, but tends to be hardy, homogeneous (alike) and located in the most habitable pockets of the planet. Because so many Class H worlds possess life forms and ecosystems already, they are seldom considered for terraformation. Class L and Class H worlds have some similarities, the criteria being that Class H worlds have pockets or zones of habitability whereas most Class L worlds are universally less conducive to humanoid life.

Class M (Minshara/Habitable)

Class M worlds, or Minshara in the Vulcan planetary classification system, are near-Earth like and generally habitable. However, they come in a wide variety of subtypes and compositions. The criteria for a Minshara class is that it must have a breathable atmosphere for baseline humanoid life, must have tolerable temperate zones conducive to plant and animal life, and must have liquid water to sustain biological life forms. Most Minshara class worlds exist in the "Goldilocks Zone" of a parent star, a swath of potential orbits that allow for liquid water.

Calidic Subtype

A Calidic Subtype

Calidic planets are hot for their classification and could be steaming jungles with saturated humidity, or baked deserts, yet they retain enough water and habitability to avoiding slipping into Class H or Class L status. Such worlds would be, by Earth standards, "Hothouse" or "Greenhouse" worlds.

Furenic Subtype

Furenic worlds of the Class M type are noted as having large, long-lasting and particularly powerful storm and wind events. Their atmospheres tend to be turbulent.

Gelidic Subtype

Gelidic Class M Worlds are locked into persistently cooler temperatures, creating expanded continental and oceanic glaciation. While not yet a Class P "Snowball Earth," a Gelidic world is near-permanently in an "Ice Age."

Gracilic Subtype

Gracilic Class M worlds have thin but breathable atmospheres. They may have close-hugging atmospheres with sea-level like conditions that rapidly become unhabitable at higher terrains, or else sea-level atmosphere of the planet is similar to 3,000 meters above sea level on Earth.

Iugosic Subtype

Iugosic worlds have extremely mountainous terrain, often rapidly rising from any sea, ocean or lake. Such worlds tend to create varied "pocket climates" forming habitable valleys but have very little land at sea level. Iugosic worlds are almost always seismically and volcanically hyper-active. A large percentage of Iugosic worlds are geologically "young."

Lacustric Subtype

Lacustric Class M worlds have most of their surface water locked up in rivers, lakes, and inland seas. Such worlds have very few (if any) expansive oceans.

Lutosic Subtype

A Lutosic Subtype

Lutosic Class M worlds have thick atmospheres that usually obscure much of the planet's surface, and have increased air pressure. Often these worlds have dense and humid atmospheres. Habitability to a Human comfort level can likely be attained at a higher elevation. Lutosic subtypes may have plants, but those plants likely rely on a source of energy other than the sun. Lutosic worlds are also (usually) observed to have low light levels.

Paludal Subtype

A Paludal Subtype

Paludal Class M worlds are noted for having a high percentage of low-lying, near or at sea-level terrain which is often marshy or swampy. More than 75% of the planet's land is low-lying.

Pelagic Subtype

Pelagic Class M worlds are approaching Class O status and have surfaces dominated by oceans to a degree that 85% of the surface is under water.

Suptic/Cenotic Subtype

These unusual worlds possess Class M environments below the planet's surface- usually in extensive cavern systems. A great deal of the planet's water is subterranean but accessible in nature. The surface of such a world may or may not be condusive to life, but has a breathable atmosphere.

Tundric Subtype

Tundric Class M worlds are not Class P and are not Gelidic, but are prone to or in the process of entering an Ice Age.

Vadumic Subtype

Vadumic Class M worlds have unusually shallow oceans, often less than a kilometer deep, and at least 25% of the ocean is under less than 100m of water.

Xeric Subtype

Xeric subtypes of Class M planets are arid for the standard and have less surface water than traditional Minshara class. They are not yet defined as Class H.

Class T (Toxic)

Toxic worlds are not conducive to life as Humans and most humanoids understand it. They have geological or atmospheric chemistries that are hostile, harmful, or lethal to most known life forms. Life has been found on such worlds (such as atmospheric archaeobacteria on Venus) but it is seldom recognized as compatible with a life matrix Humans are a part of. Toxic worlds vary widely, classified by their compositional elements more than the features of their terrain. Class T worlds can be found in every orbital zone around a star, but begin life as terrestrial (rocky) bodies. They may have thick or thin atmospheres and may or may not have metallic cores enough to generate a magnetic field.