Darth Vader: I sense a great disturbance in the Force.
Imperial Officer: My lord?
Darth Vader: How else can so many worlds be totally covered with only one terrain type without regard to latitudinal variations?
Earth is a wonderfully varied place with an amazingly diverse biosphere. On this single planet, you can find jungles, mountains, forests, deserts, prairies... we must be the most varied planet in the universe. Or you'd think so after seeing so many alien worlds trapped in solitary, homogeneous landscapes.
Many other planets and natural satellites will often be defined by a single setting. It doesn't matter if the events of the story only take place on a small portion of the planet — we are still told the entire planet has one climate; specifically, the same climate as where the story takes place. Very rarely does any planet have the same level of environmental diversity as Earth, despite being as large and having a normal orbit. An ecological equivalent to the Planet of Hats. The locals will often have a hat that resembles the human cultures that inhabit similar environments.
A creature well-suited to the local environment may be upgraded to horse status, if it's big enough.
It should perhaps be noted that we usually only get very small views of these planets. Many times there are lines to the effect that it is a fairly standard planet. Almost never are we shown or told that a planet is entirely a Single Biome Planet in television or movies, and the ones that are are almost always either very temperate, tropical, desert, ice, or water worlds, which all have a statistical probability of existing. We have several of them in our own solar system, in fact, missing only a breathable atmosphere.
Earth itself could fairly be considered a water planet. In its history, it has been an Ice planet more than once, though, as well as periods when most of the landmass was Desert (early Mesozoic) and of nearly uniform lush growth (mid-Mesozoic)note . By similar standards, Mercury could be a Desert Planet, Venus a Cloud/Volcano Planet, and Mars another Desert Planet (a cold desert this time). If you allow the moons of the gas giants, you also have Io (a Volcano Planetoid - it has been said that the entire surface of the moon is repaved in just three years by volcanic activity) and numerous Ice Planetoids (such as Europa and Enceladus). Most of the outer solar system dwarf-planets are also Ice Planetoidsnote .
Note that a Single Biome Planet is not necessarily a single climate planet. Even on planets and moons lacking atmospheres, there are bound to be variations in temperature due to latitude if the planet or moon receives a significant amount of radiant heat from a star. A planet or moon with atmosphere will of course have much more complex weather patterns due to wind and precipitation.
Notable classifications (subtropes):
- City Planets (Ecumenopolis) — Urban sprawl has taken over the entire surface of a world. Theoretically possible, but only with extreme technology and/or a constant inflow of resources from off-world. May serve as home base to a culture of Planet Looters. Often has a population in the trillions. The concept supposedly first appeared in the writings of 19th century spiritualist Thomas Lake Harris. The first recognized usage in science fiction would be Trantor in Isaac Asimov's Foundation trilogy. The planet Coruscant in the Star Wars movies would probably be the most familiar to modern audiences. The logistics of such worlds — how they get food, dissipate excess heat and so forth — can be a subject of geeky speculation, as shown in multiple Irregular Webcomics.note See also Planetville.
- Cloud Planets — The land is not where Newton wants it. If something or someone lives here, either the ground floats through the sky in chunks, or there are hover-cities— unless the natives are Living Gasbags. Either way, watch that first step. Sometimes explained by by making them Jovian planets: although no known gas giants are anywhere near habitable, there is nothing precluding the possibility of a gas giant having a layer (gas giants tend to be highly stratified) with Earth-normal atmosphere, pressure and temperature. Venus, again, is another prime example; some levels of its upper atmosphere would be pretty nice and potentially habitable—if not for those pesky sulfuric acid clouds around—and there is serious research into the possibility of floating missions or even colonies to Venus where Earth atmosphere would be used as the lifting gas and therefore settle at the layer of the Venusian atmosphere that matches Earth-normal temperature and pressure..
- Dark Planets — Like the Desert, but owe their lack of plant life to perpetual night; usually due to constant opaque cloud cover or spooky ominous fog. If inhabited, this might be the product of industrialization run amok, with the clouds being clouds of pollution. Home of the Big Bad, look for the Evil Tower of Ominousness with the perpetual lightning storm. It's like Planet Mordor. This is kind of like the real-life Venus, which even comes complete with the lightning storms. However, such planets in fiction are invariably described as "barely habitable", whereas the real version is of course completely uninhabitable. Dark Planets could also be Rogue Planets that do not orbit any star, although then there is the issue of what is keeping the atmosphere warm enough and replenishing the oxygen. Some of these planets could be tidally locked to their star with one side permanently facing it, rendering the facing side uninhabitable due to temperature and the dark side extremely cold, usually with a small habitable strip on the divide. These worlds also generate extreme weather, which can add to this atmosphere. A dark planet can also orbit a brown dwarf star, which radiates infrared heating radiation but barely any visible light, and the entirety of the latter is deep red. The appearance of the planet's sun, namely an ominous, huge black and red stripy circle in the sky, adds bonus points to the gloominess and doominess of the planet, as does the local flora, colored pitch black in a desperate attempt to catch any and all scarce photons available for photosynthesis.
- Death Worlds — Not a biome in and of itself, but can be any of the aforementioned types. This is a world where Everything Is Trying to Kill You, but you still have compelling reasons to go there. After all, except Earth (and, possibly, Mars) all other Solar System planets are unquestionably those (though Venus takes the cake, as if it's some sort of planetary Australia), and there is thriving research activity around, with a regular expedition and terraforming proposals popping up.
- Desert Planets — These look like the cheaper parts of California or gravel quarries in Wales, and are thus very common. May have aliens that act like Bedouin or Touareg, and a thriving black market on water. Multiple suns are common. Mars is sort of a desert planet, but with no breathable atmosphere, although recent discoveries pretty reliably show that it's an Ice Planet as well — it's just that all that ice is under the desert. Desert Planets are fairly realistic as these sorts of planets go, as long as there is some water. Any place that is sufficiently arid becomes a desert, but some ocean (say, 20% of the planet's surface), or underground water would be needed to support the plant life needed to create a breathable atmosphere.
- Farm Planets — If a Planet City is lucky, there will be another planet in the same system which is dedicated entirely for food production. Most of these are like a giant version of an American Midwest wheat farm. Complete with hicks. Technology level may range from highly advanced (in which case they are often largely automated with a population as low as hundreds or thousands) to feudal.
- Forest Planets — A planet whose land surface is mostly or entirely covered by forest. While Jungle Planets tend to be tropical in nature, a Forest Planet tends to have a more temperate climate with trees similar to oak, birch, redwoods and so on. Sometimes found in the form of a Forest Moon orbiting a large planet. Earth several million years ago could be considered a Forest Planet, since the warmer atmosphere and higher atmospheric humidity levels meant much more of the planet was covered in lush, tropical landscape.
- Garbage Planets — The entire planet is being used as a dumping ground for useless waste. Likely to act as home for scavengers looking to make a quick buck, treasure hunters seeking some long-lost treasure, and large numbers of mercenaries and criminals. The actual surface conditions can range from desert-like to incredibly hostile if the Phlebotinum is leaking out of ships.
- Ice Planets — Planets whose entire surfaces look like Greenland glaciers. Somewhat justified, as there actually are frozen-over planets and moons (for example, several moons of Jupiter and Saturn). Planets that normally have large oceans (like Earth) can look like this during a really deep Ice Age, and paleontologists believe that this may have happened to Earth in the past in a controversial scenario known as "Snowball Earth". The obvious question on an Ice planet is how it sustains life if there are so few plants to provide oxygen and a food chain; this paradox can be somewhat solved by allowing for a narrow equatorial band warm enough to support plant life, or by limiting life to the sea and having the food chain be based on geothermal energy/chemosynthesis (i.e. how we think life on Europa would work). It's interesting to note that the Saturn's Moon Titan, while being an "Ice Planet" of −179.2 °C, seems to be in every way just as dynamic and varied a planet as the Earthnote .
- Jungle Planets — Mind the bugs, they are positively enormous. Often home to the Cargo Cult and vulnerable to a God Guise. Expect most things that crop up in Hungry Jungle stories. Equivalent in video games is the Jungle Japes.
- Ocean Planets — These tend to have just a few, if any, mountains tall enough to breach the surface and make islands; if there are, they're prime beachfront vacation spots. Earth is arguably an ocean planet, just one with a lot of tectonic activity to create islands and continents (and even so, the average elevation of the Earth's surface is still well below sea level). This was even more true 500 million years ago, when the only life that existed was in the sea, and there was much less land above water than there is today. An extrasolar planet, GJ 1214b, has cropped up practically next door to us (a mere 42 light-years), which does appear to be an ocean planet, albeit a very hot one, and extremely uninhabitable.
- Swamp Planets — Like the Jungle, but easier to lose your shoe. (Or your ship. Just ask Luke Skywalker.)
- Twilight worlds, a.k.a. Tidally Locked Planets. While not truly single-biome, they traditionally have only about three: blazing hot desert on the day side, temperate zone of perpetual twilight at the day/night terminator, and sub-freezing wasteland on the night side.
- Vancouver Planets — Planets noted for a striking similarity to the pine-covered, mountainous oceanfront regions around the Canadian city of Vancouver (which, by an odd coincidence, is the filming location of many sci-fi television series).
- Volcano Planets — Defined by earthquakes, smoke, rivers of lava, and lots and lots of unchained mountains you don't want to climb. Featured in Revenge of the Sith; the Y-class planet in the Star Trek: Voyager episode "Demon" is also similar to this. Equivalent in video games is Lethal Lava Land. In the real-life solar system, this is a fair description of Jupiter's moon Io. Earth used to look a bit like this, too. Planetologists expect that any rocky planet will look like this in the first few hundred million years of its formation, so expect to see a lot of them. The air almost certainly won't be breathable, though, so bring your ventilator mask.
Contrast Patchwork Map. Near the polar opposite of All Planets Are Earthlike. May overlap with One-Product Planet. See also Planetville. Works in which Venus is Wet frequently depict it as a Jungle Planet, an Ocean Planet, or a Swamp Planet.
- Galaxy Express 999 visited a Dark Planet, subverted in that it's actually a rather pleasant place with lush forests, pretty flowers, low crime rates, and genial people— lovely to visit apart from the difficulty of finding your way around. At least it was...until a native Mad Scientist, having decided that her people's way of life was archaic and hopelessly out of step with the rest of the galaxy, shut off the planet's natural light-dampening field and shot an artificial light source into orbit. Everyone and everything on the planet (herself included) promptly dropped dead from photosensitivity.
- Justified on Outlaw Star with the explanation that since the planet in question is a resort planet, they terraformed it that way on purpose. Heck, it's not even a Single Biome Planet, given the existence of snow-capped mountains.
- The Five Star Stories has only two of these, out of the half-dozen or so habitable planets that orbit the eponymous stars. There's Juno, which is a relatively young planet currently in a jungle-covered phase & Pestako, a tiny, clapped out mining planet that has no natural atmosphere & is slowly being terraformed into a city planet, complete with roads so big you can see them from space. The rest are Earthlike, with some minor variations in their average temperature & terrain.
- Terraformed planets and moons in Cowboy Bebop (e.g. Ganymede seems to be a water moon, Europa a kind of Western Prairie Moon, Titan a Desert Moon...) Earth has also become one of these. As a result of being constantly bombarded by asteroids, almost all of the planet is a dry, craggy wasteland.
- Trigun is set on the planet Gunsmoke, which appears to be nothing but desert. Like Mars (or, more to the point, Arizona), it does have canyons that suggest more plentiful water in the past.
- Dragon Ball: Planet Namek, which, for all the viewer gets to see, is an ocean planet dotted with several very small islands.
- Armored Trooper VOTOMS averted this with planet Melkia, of which we see deserts, a barren wasteland ravaged by acid rain (the outskirts of Uoodo) and a Vietnam-esque lanscape of lush tropical jungles (Kingdom of Kummen). Played straight, however, with wasteland planet Sunsa (whose current inhospitality is said to have been solely caused by the devastating wars humans waged there) and desert planet Quent (which is implied to have been a much livelier place millenia ago when the precursors still lived).
- In Gargantia on the Verdurous Planet, Earth experienced an ice age a while back, and once it ended the world became a gigantic ocean. All the remaining humans live in ships that sail around in massive fleets; they power their ships by seeking out "ocean galaxies", huge swarms of bioelectric creatures that are actually solar-powered nanomachines.
- In almost every drawing or painting of Earth created prior to the famous Blue Marble photos, the Earth was apparently a single-weather-system planet, with not a cloud to be seen anywhere.
- Although Jerry Pournelle famously parodied this trope with the phrase "It was raining on Mongo that morning", the original planet Mongo in the old Flash Gordon comics is actually an aversion. It's specifically Earth-like, in that humans and near-humans can live comfortably there indefinitely without life support systems, which means it should be expected to have the full variety of potential environments as Earth...and it does. Jungles, forests, deserts, glaciers, etc. It's not a bad example of a relatively realistic habitable world, in some ways.
- The 1980s British science fiction comic Starblazer had a variety of such planets.
- City Planets: See that page
- Cloud Planets: Pelion (issue 167). The factories of Cybeset industries are suspended above the poisonous acidic atmosphere.
- Dark Planets: Largos (issue 56). It lost its sun long ago and is in an almost permanent state of darkness.
- Desert Planets: Astalia (issue 9), Delta (issue 63), Glan (issue 103), Silicon IV (issue 50)
- Farm Planets: Colonia (issue 161), Spiros IV (issue 53), Oprel (fish farming, issue 132), Vesta (issue 38)
- Ice Planets: DB/907 (issue 179), Keeron (issue 33), Mongros (issue 43), Pax Ultima (issue 166), Sartog (issue 228), Thrymheim (issue 127), Vardy (issue 87)
- Jungle Planets: Alterus (issue 71), Arenal (issue 146), Darga (issue 27), Eptiran (issue 106), Kreel (issue 144), Persephone (issue 269), Sygma 334 (issue 235), V8-Nam (issue 273), Veta (issue 5), Vloorg homeworld (issue 262), Zorg (issue 3)
- Ocean Planets: Hera (issue 90), Monta (issue 161), Oceania (issue 102), Samor (issue 34)
- Swamp Planets: Havena (issue 268), Holci (issue 161), Icon (issue 163)
- In the DC Universe:
- The planet Oa (headquarters of the Green Lantern Corp) is a Desert Planet.
- The presence of The Entity, a massive winged humanoid that is the manifestation of the White light that creates life, within Earth is the reason that Earth is NOT a Single Biome Planet, but rather has such a diverse array of life and environments.
- The Vega system alone has multiple examples.
- Dredfahl has a great deal of volcanic activity (Volcano Planet) and was a dumping ground for toxic materials from the rest of the system (Garbage Planet).
- Euphorix is a lush tree-covered world (Forest Planet).
- The planet Hnyxx is more than 90% covered by water and has several water-dwelling races (Ocean Planet).
- Karna is a warm, humid planet covered by jungles and swamps (Jungle Planet + Swamp Planet).
- White Sand: Subverted. The day side of Taldain appears to be a desert planet, but it has many unique biomes—it's just that they're all covered in sand. When some Nightsiders complain about being trapped in the desert, Kenton laughs and says they're nowhere near the desert. To prove it, he dribbles some water on the sand, which causes vines to burst out of the ground that they can then harvest for food and water. The main setting is actually a port city on the ocean.
- The Chronicles of Riddick
- In Pitch Black, the planet the plot takes place on starts as a desert planet, then turns into a night planet due to an eclipse.
- The Chronicles of Riddick starts on an ice planet, heads to a desert-ish planet, and winds up on the heat-scoured Crematoria. The latter at least has the justification of being so close to the sun that the facing side actually melts every day, but the air is still somehow breathable.
- And finally averted in Riddick, in which Riddick finds himself on what appears to be a rocky desert world. It turns out that there's reasonably fertile grasslands just a few miles away, on the other side of the mountains.
- In Starship Troopers there is an entirely single biome solar system. Even the moons are desert.
- In the TV movie Rudolph the Red-Nosed Reindeer, Earth itself seems to have become a Cloud Planet, or at least a Single Weather-System Planet. While the song's "foggy Christmas eve" might merely have left Santa socked in at the North Pole, the movie shows the entire world drowning in a pea-souper from dusk to dawn.
- Averted in Avatar. Although most scenes take place in a jungle region, far away shots show that Pandora has vast oceans as well as polar ice caps. When gathering allies they visit one Na'vi clan that's living along some sea-side cliffs and another dwelling in an area of large, open grasslands. Most of the plot just focuses on the jungle region. Word of God suggests the sequel will also show the oceans in detail.
- The setting of Hunter Prey is a desert planet.
- Kevin Costner's film Water World is set in a future where global warming has turned our earth into an ocean planet, with dry land as nothing but a legend (and science be damned!).
- Flash Gordon: Two of the moons of Mongo fit this trope. Arboria is a Jungle/Swamp Planet and Frigia is described as an Ice Planet. And all of these and Mongo appear to be Island Planets floating inside a weird, glowing nebula-like thing with a vortex as an entryway. It's not a conventional solar system as we would know it. Its implied that these are what is left of planets that have been attacked by Ming to prevent them from becoming a threat.
- Beetlejuice. The afterlife (ghost) version of Saturn is a Desert Planet (complete with Sand Worm) instead of a gas giant.
- In the early script, it was the moon Titan. Though in the film, the giant planet seen in the sky could be Saturn.
- Spaceballs. The protagonists crash-land on the "desert moon of Vega", which bears a startling resemblance to Tatooine in A New Hope.
- Andromeda's standard planetside-setting is the Vancouver Pine Forest Planet. This is somewhat lampshaded when the trees are once referred to as "terraforming Pines".
- Battlestar Galactica (1978). In "The Gun on Ice Planet Zero", the surface of the planet Arcta is entirely covered by ice and snow, with a constant blizzard blowing overhead.
- Doctor Who: Usually, only a small part of any given world is shown, so it is not possible to generalize about the entire planet. However, there are a few cases where a world is explicitly stated as being a Single Biome Planet:
- It's averted in "The Keys of Marinus". Most episodes take place in different environments. This was back in 1964.
- Aridus from "The Chase" is a desert planet.
- "Silence in the Library"/"Forest of the Dead" has the titular Library, which is an artificially-constructed planet.
- "Planet of the Dead": San Helios used to be a city planet, but was turned into a desert by a Horde of Alien Locusts.
- Temporarily applied to the Earth in "In the Forest of the Night".
- The third (second?) season of Lexx has the Lexx trapped in orbit between Fire, a volcanic planet covered in endless desert, and Water, a planet almost entirely covered by water. It could be somewhat justified as the planets are actually Hell and Heaven respectively, with the former being ruled by what's hinted to be the Devil himself.
- Lampshaded on the episode of The Muppet Show where the cast of Star Wars are the guest stars. "Seems we've landed on some sort of comedy variety show planet!"
- Deconstructed in Power Rangers RPM, which takes place on a Desert Planet. The thing is, three years before the series takes place, it was earthlike - and the series takes place in a Please Insert New City Name version of Boston, most certainly not in a desert region, showing just how much of the planet is sandy wasteland. The cause of the mass desertification is subtly implied to be nuclear carpet-bombing. The background radiation is so high that long-distance communication is all but impossible, and orphans with cancer are prevalent.
- Red Dwarf
- The series featured "ice planets" and "lava moons", and one ocean planet they picked for a fishing holiday.
- Red Dwarf also has a tendency to make many planets Earth-like. Earth is the only planet to evolve life in this show. Any planet where the cast encounters "life" has previously been wholly or partially terraformed by humanity, and the inhabitants originate from human science, in one way or another.
- One of the parallel worlds in Sliders has Earth turn into a desert world after all the water dries up... somehow. Nations no longer exist, water is extremely valuable, and lawless gangs are free to do what they want.
- Both SG-1 and Atlantis generally avert this trope by rarely showing much of the entire planet other than a small (i.e walkable) area around the Stargate. The Stargate itself tends to be in a Vancouver-like pine forest or nearby area, which is eventually lampshaded by the characters: the assumption being that the creators of the gate must have only placed Stargates on worlds and areas where they liked to live. The actual fact being that life on all of those worlds were recreated by some of the Stargate creators who survived a plague that destroyed everything.
- Subverted in the Stargate SG-1 episode "Solitudes", wherein Captain Carter manages to get out of the cavern she and Colonel O'Neill are in, revealing the surface is a desolate ice planet. Only, it turns out they're on Earth, in Antarctica.
- Subverted in Stargate Atlantis with the planet where they find Atlantis. They assume it to be an ocean world, but later find out that it has several large land-masses that are inhabitable. Atlantis was in the ocean because it couldn't very well submerge into the ground when the Ancients needed to hide it. Additionally, the planet's weather patterns are different: the continents are still a considerably smaller percentage of the surface than Earth, which means hurricanes can reach strengths virtually unheard-of on Earth (as seen in the two-parter "The Storm" and "The Eye").
- In Stargate Universe most planets might as well be of the single biome type; None of the crewers can explore further. With a timer on how long they can get back, they'll never know if this was truly a total desert planet or was just the Sahara of an Earth.
- Star Trek:
- The series has a tendency to either have totally Earth-like planets (class M) or Single Biome Planets. At least in the Original Series, they used so many Class M planets in order to keep production costs down. Most planets home to advanced civilisations have some degree of weather control, although the extent this is used to change the biome varies with some simply using them to prevent dangerous weather.
- Star Trek: The Original Series
- In the episode "The Savage Curtain", the surface of the planet Excalbia is completely covered with molten lava, making it a Volcano Planet.
- In "The Naked Time", the planet Psi-2000 is described as a frozen wasteland (i.e an Ice Planet).
- Ferenginar, the Ferengi homeworld, is a class M planet that's home to virtually constant, planet-wide torrential downpours, due to weather control technology and the Ferengi's preference for rainy days.
- Andoria, home of the Andorians, is an Ice Moon.
- Vulcan is somewhere between Earth-like and a Desert Planet. Star Trek: Deep Space Nine once featured a minor character (a date of Jake Sisko's) who said she and her parents often visited lush forested parks on Vulcan. So much so, she thought it was a Forest Planet before realizing that that is not the biome most people associate with Vulcan. Also, she didn't realize that Vulcan had any indigenous people.... You know, come to think of it, Nog may have had a point in suggesting she just keep quiet.
- The homeworld of the Breen, who are always shown wearing opaque full body environmental suits, is known mainly as an Ice Planet, but according to Weyoun is "actually quite temperate". The planet itself is never actually seen, and this confusion serves to reinforce the mystique of the Breen.
- Star Trek: Voyager:
- In "Thirty Days" the ship comes across an ocean world with no landmass whatsoever. In its center is a machine created by Precursors that stops the water from dissipating out into space.
- The Ocampan home planet is a desert planet where the only really habitable areas are underground. This is justified in that the Caretaker accidentally caused an ecological disaster that eliminated all the water from the surface.
- Risa, the "pleasure planet", uses technology to make the entire planet into a tropical paradise, as long as your idea of paradise is a sunny day in Hawaii (as noted before, the Federation consists of a large number of diverse societies with a large number of diverse homeworlds, so relaxing at the beach may not suit everyone the same).
- BIONICLE has Bara Magna, which is almost entirely desert, although it does have a few oases as well as icy peaks towards the north. Its two moons, Aqua Magna and Bota Magna, also count towards this trope; Aqua Magna is covered entirely with ocean, and Bota Magna is covered entirely with jungle. Bara Magna and its moons were originally a single planet, Spherus Magna, that had all three biomes before The Shattering, and it was the destiny of Mata Nui and Makuta Teridax to merge the moons with the planet to reform Spherus Magna.
- There was a LEGO Space line simply called Ice Planet 2002. It centered on three astronauts exploring Krysto, a planet whose terrain is primarily made up of ice.
- In the North American version of the Slizers storyline, each of the Throwbots originated from a Single Biome Planet appropriate to that Throwbot's element. For example, Torch came from a volcanic planet while Ski came from an ice planet.
- While the "real" planets (Earth and Alternia) are naturally realistically varied as far as we can tell, all of the Lands generated by Sburb, in addition to the Skaian Battlefield, are fairly creative examples of this (such as a planet entirely of blue stone covered by glowing blue forests and lakes and rivers of tar, or one covered in molten lava dotted with islands of metal and clockwork). Justified in that being single-biome planets is the entire point of the Lands as game constructs.
- In the Alpha timeline, the Condesce floods the Earth, artificially turning it into an Ocean Planet to make it more hospitable for an aquatic alien such as herself.
- As well as giving the quote above, Irregular Webcomic! lampshades this in one of its podcasts: when Admiral Ackbar calls Endor a forest moon, C-3PO corrects him heavily, saying that it has a small ocean, two deserts, and a mountain range with an extensive cave system. Thankfully, by then, he was turned off.
- Shortpacked! shows us how theme planets sometimes don't work.
- Lampshaded (of course) in Darths & Droids, where they're the result of the DM not having much time to design a proper ecosystem.
Luke: Huh. A swamp. What are the odds of that?
R2D2: Higher than you might expect.
Luke: Maybe we should move the ship.
R2D2: I ... have the feeling that might be a waste of time.
- In Red vs. Blue the Halo-map Sidewinder is "a planet made entirely out of ice. It was really fucking cold."
- Satirized in CollegeHumor's Troopers: "The Swamp Planet".
"50 years ago Dread Trooper scouts landed in a swamp on our planet and for some reason didn't bother exploring anywhere else! If they'd gone one mile to the left, they would have found some beautiful beach front condos. But they didn't. And now we're the "swamp planet". How do you think that makes me feel?"
- Part of #3 of Cracked's 6 Sci-Fi Movie Conventions (That Need to Die).
- The planet "Edict Zero" of Edict Zero Fis is assumed to be an ocean world with only five islands.
- The Escapist has an article examining the realism of single-biome planets in Star Wars.
- Futurama frequently makes fun of this, and the Planet of Hats, as every world the crew visits seems to have a single defining characteristic; Dr. Zoidberg's home planet of Decapod 10 is all beaches (referred to as "the Mud Planet" by its ambassador), Kif's is all swamp, etc. A notable example is the Nude Beach Planet, the entire planet apparently a coastline.
- Nearly every planet in War Planets. Admittedly, this was largely because the play-sets were designed first, but the writers have nobody but themselves to blame for the set-up whereby the inhabitants of the desert planet could only survive — on the planet on which they had evolved — by stealing water from the ice planet. This case, however, is justified by virtually every planet being designed and built, not evolved. The Cluster in particular was created as a quartet of interdependent worlds. The adaptation took it a lot further. Bone provides food, Rock provides minerals, and Fire provides energy. They even have world engines inside.
- Invoked on Invader Zim—when the Irkens conquer the planet Blorch (home of the Slaughtering Rat People), they simply destroy everything and, on the Tallests' whim, declare it will be rebuilt as a parking garage planet. Presumably this is also the back story of Foodcourtia (a planet of restaurants), Conventia (the conventional hall planet) and Callnowia (which is covered in factories that Irkens can order things from).
- SilverHawks features the Dollare Bank, a money vault planet, and Penal, a prison planet.
- In most series, Cybertron is a city planet. Many series, especially Energon and Cybertron, contain further examples. Of course, a Transformer's requirements for survival are a lot more forgiving than a human's.
- There's also the planets in Transformers: Cybertron. Velocitron the Speed Planet is a Desert Planet, the Jungle Planet is... well, that... and Gigantion is a City Planet.
- In Energon and Cybertron, most planets are named "[Biome] Planet," or will have a name but be nicknamed [Biome] Planet, and the nickname will see more use than the name. In addition to the above examples, there's Blizzard Planet and Circuilt Planet (all racecourses. Same hat as Speed Planet, but it's covered with highways, while Speed Planet, as far as depicted onscreen, is all desert.)
- In both the comic and cartoon humans visit Cybertron and are able to breathe with no problems, although logically there is no reason for there to be an atmosphere breathable for humans. The Beast Machines series seems to offer the suggestion that Cybertron was originally built around a habitable planetoid and that somehow has retained its atmosphere. This was actually the explanation given for the similar world of GoBotron in the Go-Bots cartoon series.
- This is averted in Transformers Prime, as Jack has to wear a spacesuit in order to breathe on the planet. Megatron later captures him along with Raph and Miko and forces Optimus to give up the Omega Keys and surrender, or he'd release them from their airtight capsules and let them die on the planet's surface. He later planned to use the Omega Lock to terraform Earth into a second Cybertron, despite knowing that doing so would kill everyone on the planet as well.
- If Cybertron was originally Earth-like, the machines might incorporate a programming directive to keep it habitable that is so basic to their operating systems that they don't even think about it, they just do it.
- Some series have partially subverted this and made it surprisingly diverse for a planet made of metal. It often has its own mountains, canyons, and even a sea of rust somehow. It's still made entirely of metal, though.
- Skyland is set on a cloud planet.
- Gobotron from Challenge Of The Gobots is a city planet. This is justified in that the planet's biosphere was destroyed ages ago in the inhabitants' civil war, forcing the race to become cyborgs. They then set about salvaging their now-dead home by converting it into a technology-based world.
- Star Trek: The Animated Series
- "The Jihad". From what we were shown of it, the planet where the Soul of the Skorr was kept appeared to be a Volcano Planet.
- "The Slaver Weapon", based on Larry Niven's short story "The Soft Weapon". As in the original short story, one of the planets in the Beta Lyrae star system is a "icy little blob of a world", AKA an Ice Planet.
- "The Ambergris Element". The planet Argo's surface is almost completely covered by water, making it a Water Planet. It used to be more like Earth but violent seismic disturbances caused almost all of the land to sink beneath the waves.
- In the old Flash Gordon animated series, this trope was averted (as in the comic strip that was the inspiration for it) by Mongo, which actually boasts a wide variety of habitable environments ranging from polar ice to tropical jungle, passing through various shades of desert and temperate forest in between, along with underground labyrinths.
- Winx Club has two. Andros is a water planet with a few scattered islands spread out. This works out well for the mermaid population that lives there. The Omega Dimension is an ice planet where criminals are sent. Just about the entire planet is frozen, so anyone stuck on it has to rely on magic or scattered gadgets to survive.
- In American Dad!, one of the few things known about Roger's home planet is that it's an ice planet. Roger has stated it has an atmosphere roughly 400 degrees colder than Earth, and he himself has shown an immunity to hypothermia.
- Young Samson & Goliath episode "The Monsteroids". Samson and Goliath need to get to a Volcano Planet planetoid orbiting the Earth in order to stop the villain based there.
- Space Ghost. The episode "Jungle Planet" takes place on one. It's covered with the standard trees, hanging lianas, thick undergrowth and so on.
- Roughnecks: Starship Troopers Chronicles has a different planet each season.
- Pluto is an ice planet, of course, while Zephyr four campaigns later is actually a comet.
- Hydora's an ocean planet for the most part.
- Tophet is mostly desert with a lot of volcanoes.
- Tesca is a mix of jungle and swamps, also the only planet in the series where humans don't need pressure suits to breathe.
- Klendathu is a barren death world, period.
- Look at Corot-7b, which is even being called "the lava planet".
- GJ 1214b appears to be a prime candidate for an ocean planet. It's estimated that the ocean on its surface would be roughly three to four thousand miles deep. Yes, the ocean depth is a large percentage of the total radius of the planet. Additionally, because the planet is definitely hotter than boiling point, the ocean doesn't have a defined surface. Instead the atmosphere just gets thicker and thicker as you go down until it becomes as dense as water, which can't compress anymore, meaning the ocean and atmosphere just blend together.
- Today, Earth is the only aversion in the solar system. In the very early stages of formation, Earth was a lava planet, and if the Giant Impact Hypothesis of the Moon's origin is correct, the Earth and the Moon were balls of magma for a while after the impact. It was probably a kind of ice planet at various points in the Cryogenian era (850-625 million years ago), particularly during the Marinoan Glaciation. This hypothesis is called (fittingly) "Snowball Earth". During Earth's Pangaea period, it was largely one huge desert surrounded with one gigantic ocean. Later, there was a period when the entire planet was a warm, moist planet covered with jungles - even Antarctica. This is how most of our coal reserves were created, by the way. Even later, the supercontinent Pangaea was almost completely made up of deserts; while Pangaea broke up during the Cretaceous, a hypothesis claims that the entire Earth may have had the exact same climate during this period due to unusual composition of the atmoshpere at the time. Possibly the closest fit to the above archetypes today would be an Ocean World, as the surface is over 70% water.
As for the other planets...
- Venus has an extremely dense atmosphere that distributes heat very efficiently around the planet, so its surface of volcanoes and sulfuric acid is hot enough to melt lead from equator to pole and through the 60-Earth-day night. It could with a bit of engineering be a Cloud Planet, however: Earth atmosphere is a lifting gas on Venus, and conveniently the spot at which its density equals the density of the Venusian atmosphere is also where Venusian temperature and pressure is Earthlike—so if you put a colony in a giant bubble of ordinary Earth air, it would float in a stable manner on Venus in exactly the spot you want it to.
- Mars is basically a desert world. A very cold desert world—to the point where it is also an ice world: there's lots and lots of ice on Mars, both at the surface (in the polar ice caps, which are predominantly water ice) and below it (much if not most of Mars actually has what amounts to frozen groundwater—albeit frozen groundwater mixed with nasty chemicals—below the surface layer of desert rocks and dust). It also snows dry ice (frozen carbon dioxide) in the winter in the polar regions.
- Jupiter and Saturn are basically liquid hydrogen planets, with very large hurricanes and possibly rocky cores. Neptune and Uranus are more like "slush planets".
- Everything else (Mercury, most moons, asteroids, etc.) are mostly airless rocks or ice balls (like Pluto and Charon).
- Barring intervention, in a few billion years, the increasingly hot Sun will boil off the Earth's oceans, leaving a desert planet. Before, that is, it gets hot enough to turn it into a lava planet again.
- Some of the moons also count:
- Jupiter's moon Europa's (and Saturn's moon Enceladus') surfaces are composed of one giant ice-covered ocean. Both are also prime contenders for extraterrestrial life.
- If you want a volcano world, look no further than Io. Most moons aren't large enough to retain sufficient internal heat for volcanic activity, but Io is being constantly stretched and crushed by tidal forces from Jupiter's gravity, like a stress-ball made of rock.
- Titan (Saturn's moon) would be a dark ice planet. It's far from the sun, and the atmosphere has an organic haze that blocks most of the sunlight that does reach itnote . It does have lakes, though — they're just made of liquid methane, and even hydrocarbon snow covering its hightest mountains. Any water on Titan's surfacenote would likely be called "rocks" by the locals as the melting point of water ice for them would be like hot magma to us. This moon partially subverts this trope too, having the mentioned hydrocarbon lakes on its poles while having extensive dunefields (of ice and hydrocarbons too), the largest of the Solar System, on its equatorial regions. However all share the same orange, murky sky and a temperature of -180°
- There is a planet made entirely out of diamond. PSR J1719-1438b is also a diamond planet, but it originated as a carbon-oxygen white dwarf, and was then cut down to planetary mass by intense irradiation from its partner (a pulsar).