Class M planet
Encyclopedia
Planet
A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...
s and planetoids in the Star Trek
Star Trek
Star Trek is an American science fiction entertainment franchise created by Gene Roddenberry. The core of Star Trek is its six television series: The Original Series, The Animated Series, The Next Generation, Deep Space Nine, Voyager, and Enterprise...
science fiction
Science fiction
Science fiction is a genre of fiction dealing with imaginary but more or less plausible content such as future settings, futuristic science and technology, space travel, aliens, and paranormal abilities...
media franchise
Media franchise
A media franchise is an intellectual property involving the characters, setting and trademarks of an original work of media , such as a film, a work of literature, a television program or a video game. Generally, a whole series is made in a particular medium, along with merchandising and endorsements...
. In the Star Trek: Enterprise
Star Trek: Enterprise
Star Trek: Enterprise is a science fiction television series. It follows the adventures of humanity's first warp 5 starship, the Enterprise, ten years before the United Federation of Planets shown in previous Star Trek series was formed.Enterprise premiered on September 26, 2001...
series, T'Pol
T'Pol
Commander T'Pol is a fictional character played by Jolene Blalock in Star Trek: Enterprise. She is a Vulcan who serves as the science officer aboard the starship Enterprise.-Concept and creation:...
(Jolene Blalock
Jolene Blalock
Jolene K. Blalock is an American film and television actress and model, perhaps best known for playing the Vulcan T'Pol on the UPN science fiction series Star Trek: Enterprise. The star of several feature films, she is a regular guest star in television films and series.- Early career :A popular...
) uses the Vulcan
Vulcan (Star Trek)
Vulcans, or sometimes Vulcanians, are an extraterrestrial humanoid species in the Star Trek universe who evolved on the planet Vulcan, and are noted for their attempt to live by reason and logic with no interference from emotion. They were the first extraterrestrial species in the Star Trek...
term Minshara class, which may be the origin of the later Federation designation.
Their atmosphere
Atmosphere
An atmosphere is a layer of gases that may surround a material body of sufficient mass, and that is held in place by the gravity of the body. An atmosphere may be retained for a longer duration, if the gravity is high and the atmosphere's temperature is low...
s comprise nitrogen
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...
and oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
and have an abundance of liquid water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
necessary for carbon
Carbon
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...
-based life to exist. Extensive plant and animal life often flourishes; often, a sentient race is also present. Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
is a textbook example of a Class M world; other Class M planets that appear throughout the franchise include Vulcan, Cardassia Prime, Bajor, Betazed, Romulus, Ferenginar, and Qo'noS.
In fiction, Class M planets are similar to those suggested to be found in the real-world astronomical theory of life supporting planets found within the habitable zone
Habitable zone
In astronomy and astrobiology, a habitable zone is an umbrella term for regions that are considered favourable to life. The concept is inferred from the empirical study of conditions favourable for Life on Earth...
(HZ), sometimes also referred to as the 'Goldilocks' zone.
The "M" stood for Majel (Majel Barrett
Majel Barrett
Majel Barrett-Roddenberry was an American actress and producer. She is perhaps best known for her role as Nurse Christine Chapel in the original Star Trek series, Lwaxana Troi on Star Trek: The Next Generation, and for being the voice of most onboard computer interfaces throughout the series...
) who, in Gene Roddenberry
Gene Roddenberry
Eugene Wesley "Gene" Roddenberry was an American television screenwriter, producer and futurist, best known for creating the American science fiction series Star Trek. Born in El Paso, Texas, Roddenberry grew up in Los Angeles, California where his father worked as a police officer...
's words, "made his life possible".
Other planet classifications
Class A, B and C : Typically small, young planets whose class depends on their age and solidity of their cores.Class D : Class D objects are planetoids like asteroid
Asteroid
Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...
s and some moon
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
s. Regula, the site of the underground second stage of the Genesis experiment in Star Trek II: The Wrath of Khan
Star Trek II: The Wrath of Khan
Star Trek II: The Wrath of Khan is a 1982 American science fiction film released by Paramount Pictures. The film is the second feature based on the Star Trek science fiction franchise. The plot features James T...
, is a Class D planetoid. The USS Voyager
USS Voyager (Star Trek)
The fictional Intrepid-class starship USS Voyager is the primary setting of the science fiction television series Star Trek: Voyager. It is commanded by Captain Kathryn Janeway....
also encountered Class D planets in the Delta Quadrant, one in the Star Trek: Voyager
Star Trek: Voyager
Star Trek: Voyager is a science fiction television series set in the Star Trek universe. Set in the 24th century from the year 2371 through 2378, the series follows the adventures of the Starfleet vessel USS Voyager, which becomes stranded in the Delta Quadrant 70,000 light-years from Earth while...
episode "Gravity
Gravity (Star Trek: Voyager)
"Gravity" is an episode of Star Trek: Voyager, the 13th episode of the fifth season. The episode has an average rating of 3.6/5 on the official Star Trek website .-Plot:...
" and one in the episode "Emanations".
Class E, F and G : Typically, Proto-Earth-sized planets whose class depends on their age and solidity of their cores.
Class H : Class H planets appear in the series as harsh desert
Desert
A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...
worlds. The planet Tau Cygna V visited by the USS Enterprise-D
USS Enterprise (NCC-1701-D)
The USS Enterprise is a 24th century starship in the Star Trek fictional universe and the principal setting of the Star Trek: The Next Generation television series...
in the Star Trek: The Next Generation
Star Trek: The Next Generation
Star Trek: The Next Generation is an American science fiction television series created by Gene Roddenberry as part of the Star Trek franchise. Roddenberry, Rick Berman, and Michael Piller served as executive producers at different times throughout the production...
episode "The Ensigns of Command
The Ensigns of Command (TNG episode)
-Plot:The Enterprise crew receives an automated message from the enigmatic Sheliak: Remove the humans on Tau Cygni V in four days. However, this is not a simple warning or directive. The Sheliak are a non-humanoid species with little regard for human life and would exterminate any humans found in...
" was designated as a Class H world.
Class I : Class of gas giant
Gas giant
A gas giant is a large planet that is not primarily composed of rock or other solid matter. There are four gas giants in the Solar System: Jupiter, Saturn, Uranus, and Neptune...
, larger than Class J, and smaller than Class S and T.
Class J and T : Class J and Class T planets are gas giant
Gas giant
A gas giant is a large planet that is not primarily composed of rock or other solid matter. There are four gas giants in the Solar System: Jupiter, Saturn, Uranus, and Neptune...
s. Class J are smaller than Class T which are considered "super", or "ultra", gas giants. In the Star Trek: Deep Space Nine
Star Trek: Deep Space Nine
Star Trek: Deep Space Nine is a science fiction television series set in the Star Trek universe...
episode "Starship Down
Starship Down (DS9 episode)
"Starship Down" is an episode of Star Trek: Deep Space Nine, the seventh episode of the fourth season.-Plot:The Defiant carries the senior staff of Deep Space Nine into the Gamma Quadrant for trade negotiations with a Karemma named Hanok. As the Dominion disapproves of trading with the Alpha...
", the USS Defiant
USS Defiant
The USS Defiant is a fictional starship in the television series Star Trek: Deep Space Nine and the feature film Star Trek: First Contact...
enters the atmosphere of a Class J gas giant to rescue the crew of a Karemman ship attacked by the Jem'Hadar
Jem'Hadar
In the fictional Star Trek universe, the Jem'Hadar are the shock troops of the powerful Dominion located in the Gamma Quadrant. Genetically engineered for strength and resolve, they are also short-lived and believe that "victory is life." They are bred to perceive the Founders, enigmatic...
. The USS Voyager encounters a Class T Super-Giant in the Delta Quadrant with "radiogenic" rings in the Voyager episode "Good Shepherd".
Class K : Class K planets are barren worlds with no native life. However, through terraforming
Terraforming
Terraforming of a planet, moon, or other body is the hypothetical process of deliberately modifying its atmosphere, temperature, surface topography or ecology to be similar to those of Earth, in order to make it habitable by terrestrial organisms.The term is sometimes used more generally as a...
, they can be made into Class M worlds. In the original Star Trek series
Star Trek: The Original Series
Star Trek is an American science fiction television series created by Gene Roddenberry, produced by Desilu Productions . Star Trek was telecast on NBC from September 8, 1966, through June 3, 1969...
episode "I, Mudd
I, Mudd (TOS episode)
"I, Mudd" is a second season episode of Star Trek: The Original Series first broadcast November 3, 1967, and repeated April 5, 1968. It is episode #37, production #41, and was written by Stephen Kandel, based on a story by Gene Roddenberry and directed by Marc Daniels...
", the planet Mudd was designated in dialogue as Class K.
Class L : Class L planets are barely habitable worlds with primitive ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
s. In "The Chase
The Chase (TNG episode)
"The Chase" is the 20th episode in season 6 of the science fiction television series Star Trek: The Next Generation.-Overview:Four competing expeditions — Federation, Klingon, Cardassian, and Romulan — attempt to solve a genetic puzzle that proves to be the key to why Star Treks version...
", the planet Indri VIII is indicated in dialogue as Class L. In "The 37s", the planet on which Amelia Earhart
Amelia Earhart
Amelia Mary Earhart was a noted American aviation pioneer and author. Earhart was the first woman to receive the U.S. Distinguished Flying Cross, awarded for becoming the first aviatrix to fly solo across the Atlantic Ocean...
and others are stranded is a Class L planet with an oxygen–argon atmosphere. In "Muse
Muse (Star Trek: Voyager)
"Muse" is an episode of Star Trek: Voyager, the 22nd episode of the sixth season.-Plot:An enraptured audience watches a play in a stone amphitheatre. The main characters are called B'Elanna Torres and Harry Kim, and they are on an adventure seeking dilithium when they are in a shipwreck. Harry gets...
", the planet on which B'Elanna Torres
B'Elanna Torres
B'Elanna Torres is a main character in Star Trek: Voyager played by Roxann Dawson. She is portrayed as a half-human half-Klingon born in 2349 on the Federation colony Kessik IV. Torres joined the Maquis in 2370 and was serving on the Val Jean when brought to the Delta Quadrant...
' shuttle crash lands is described as a Class L planet, which also supports Bronze Age
Bronze Age
The Bronze Age is a period characterized by the use of copper and its alloy bronze as the chief hard materials in the manufacture of some implements and weapons. Chronologically, it stands between the Stone Age and Iron Age...
humanoid life. In "Timeless", the USS Voyager crashes into a Class L planet with an arctic climate. In "The Ascent", Quark
Quark
A quark is an elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. Due to a phenomenon known as color confinement, quarks are never directly...
and Odo crash-land on a desolate Class L planet.
Class N : Class N planets have a reducing environment and are barren and rocky with extremely high surface temperatures caused by thick atmospheres containing carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
and corrosive
Corrosion
Corrosion is the disintegration of an engineered material into its constituent atoms due to chemical reactions with its surroundings. In the most common use of the word, this means electrochemical oxidation of metals in reaction with an oxidant such as oxygen...
sulfides. In "Night Terrors
Night Terrors (TNG episode)
"Night Terrors" is the 91st episode of the science fiction television series Star Trek: The Next Generation.-Plot:The Enterprise is searching a binary star system in an effort to find the USS Brattain, a Federation science vessel which went missing a month previously...
", Class N environments were mentioned as the ideal places to use oxidizer-free
Redox
Redox reactions describe all chemical reactions in which atoms have their oxidation state changed....
explosives. The Tholian
Tholian
Tholians are a fictional starfaring and extremely territorial race in the Star Trek fictional universe. The Tholian home nation is the Tholian Assembly, which inhabits an area of space in the Alpha Quadrant, near the Cardassian Union and the Badlands....
are said to have come from an N Class planet in the Star Trek: The Lost Era book The Sundred. The game Star Trek: The Next Generation - A Final Unity
Star Trek: The Next Generation - A Final Unity
Star Trek: The Next Generation – A Final Unity is a computer game by Spectrum HoloByte, based on the Star Trek universe.The cast of Star Trek: The Next Generation reprise their roles, providing the voices of their respective characters.-Plot:...
mentions that Class N planets are more related to Class M with the key difference being a higher ratio of water to land.
Class O and P : Planets covered almost completely with water (class O), or water–ice (Class P).
Class Q : Planets with continually changing environments caused by peculiar orbits, an orbit around a variable output star, or some other factor which causes conditions to drastically change over time.
Class R : A rogue planetary body, which is one that does not orbit a star but drifts freely in space. However, not all rogue planets are classified as Class R; for instance, in Star Trek: Deep Space 9 episode "The Search
The Search (DS9 episode)
"The Search" is the title of a two-part episode of Star Trek: Deep Space Nine, the first episode of the third season. It marks the first appearance of the starship USS Defiant, which plays a large role throughout the rest of the series...
", the Founders homeworld in the Omarion Nebula is referred to as a "rogue" Class M planet. But this is probably a rare situation as most planets that don't belong to a star system would not be able to support life.
Class S : Class of gas giant
Gas giant
A gas giant is a large planet that is not primarily composed of rock or other solid matter. There are four gas giants in the Solar System: Jupiter, Saturn, Uranus, and Neptune...
smaller than Class T and the next larger size up from Class I.
Class T : The largest class of gas giant
Gas giant
A gas giant is a large planet that is not primarily composed of rock or other solid matter. There are four gas giants in the Solar System: Jupiter, Saturn, Uranus, and Neptune...
. Smaller gas giants are, in order of decreasing size, Class S, I, and finally J.
Class Y : Class Y planets are referred to as "Demon" worlds, where surface conditions do not fall into any other recognized category. Such worlds are usually hostile and lethal to humanoid
Humanoid
A humanoid is something that has an appearance resembling a human being. The term first appeared in 1912 to refer to fossils which were morphologically similar to, but not identical with, those of the human skeleton. Although this usage was common in the sciences for much of the 20th century, it...
life. If life develops on these worlds they usually take on many bizarre forms, like living crystal or rock, liquid or gaseous physical states, or incorporeal
Incorporeal
Incorporeal or uncarnate means without the nature of a body or substance . The idea of incorporeality refers to the notion that there is an incorporeal realm of existence, or "place", that is distinct from the corporeal or material universe. Incorporeal beings or objects are not made out of matter...
, dimensional, or energy-based states. In the series, examples of Class Y "Demon" planets include Tholia, the "Silver Blood" planet discovered by the USS Voyager in the Delta Quadrant in the episode "Demon
Demon (Star Trek: Voyager)
"Demon" is an episode of Star Trek: Voyager, the 24th episode of the fourth season. The episode has an average rating of 3.2/5 on the official Star Trek website .-Plot :...
" and later mentioned in "Course: Oblivion", and the home world of the incorporeal Medusans.
Class X and Z : Reserved for other designations of "demon" planets.
See also
- List of Star Trek planets (A–B)
- List of Star Trek planets (C–F)
- List of Star Trek planets (G–L)
- List of Star Trek planets (M–Q)
- List of Star Trek planets (R–S)
- List of Star Trek planets (T–Z)