History Main / AllPlanetsAreEarthLike

Often {{justified|Trope}} by mentioning {{terraform}}ing; series without terraforming invariably have many life-bearing planets that are perhaps more similar to Earth than most would consider plausible.[[note]]We don't actually ''know'' how common or uncommon Earth-like planets are in RealLife, and thus it's hard to judge "realism" here objectively. For what it's worth, NASA's Kepler mission so far suggests ''maybe'' one in about 30,000 stars might have a planet that's Earth-like in terms of size and orbit, at least, though not necessarily in terms of atmosphere or other important details. There are estimated to be between 200 and 400 billion stars in the Milky Way, so that's at least six million inhabitable planets in those terms, before counting near-Earth-sized moons...[[/note]] Hell, even with terraforming, there still would not be too many planets in one solar system that might be human-inhabitable without some sort of huge sunlight-focusing and gathering apparatus in orbit, since the planets' distance to the sun seems to be the main factor. There is also some theories that an Earth-like planet would be the ideal type for (carbon-based) life (but again, this is just a theory). Additionally, even if a planet is terraformed, it still would look mostly the same as it did before, except a different color (if Mars were terraformed, it would still have its volcanoes and craters).

* In ''Anime/LegendOfGalacticHeroes'', all planets shown in the series could be mistaken for locations in Earth, with those of one faction more thematically attuned to 19th Century Germany.

* ''VideoGame/{{Stars}}'' averts the trope. Part of defining an alien race is specifying its ideal and habitable range for temperature, gravity, and radiation, which determines which planets your colonists can survive or thrive on.

* In the ''Literature/{{Dune}}'' universe there presumably are plenty of non-Earthlike worlds, but they're not mentioned because nobody lives there. The ''least'' Earthlike world is Dune/Arrakis itself, and people only live ''there'' because it's the only place Spice is found. Salusa Secundus is apparently a fairly close second, and it's used as a prison planet and training/recruiting ground for the Emperor's Sardaukar shock troops.

** It takes Chekhov a long time to find a completely lifeless planet to test a {{Terraforming}} device in ''Film/StarTrekIITheWrathOfKhan''. Implying that there's life almost everywhere.
** ''Film/StarTrek'' has Delta Vega, close enough to Vulcan that it can be seen in Delta Vega's sky but the only inhabitants are two non-Vulcan personnel in a Starfleet base. You'd think the Vulcan's would have colonized this before developing the warp drive.

** Zigzagged in ''[[Film/StarTrekIITheWrathOfKhan The Wrath of Khan]]''. The planet Khan was found on had been Earth-like but had since become fairly toxic.

* In the '90s ''WesternAnimation/XMen'' cartoon, a passing Shiar ship was bored that they had to map out a section of the universe filled with uninhabited worlds. This was the section that Dark Phoenix fried. Note, this is more of a case of softening her FaceHeelTurn, as in the original comics she ''did'' destroy inhabited worlds; and some people consider that unforgivable.

* The Beta Caeli system in ''VideoGame/AlienLegacy'' has not one but ''two'' Earth-like planets, named after the Greek goddesses/Titanesses Rhea (mother of the gods) and Gaea (earth goddess). Gaea is the third planet like Earth but lacks a satellite. Despite this, it has plant and animal life, even though it would be difficult for them to evolve without tides. Rhea is the second planet like Venus but has the same conditions and even life forms as Gaea. The game implies the presence of a Moon-sized satellite prevented a Venus-like greenhouse effect. The rest of the planets are similar to Solar System planets. All planets (including satellites and asteroids) except for gas giants are colonizable. However, the late-game reveal that [[spoiler:the two habitable planets were seeded by the [[AbusivePrecursors H'riak]]]] may imply that this is not a natural occurance. The existence of the Centaurians also implies a habitable planet in the Alpha Centauri system, although whether it's habitable for ''humans'' is anyone's guess, as [[InscrutableAliens nothing is known about the Centaurians]] except that they're AbsoluteXenophobes.

* {{Justified}} in ''ComicBook/MickeyMouseFrontierChronicles'', as it's mostly set on [[NumberedHomeworld Earth 32]], a human colony so similar to Earth it was named after it as they do with their colonies closer to Earth in terms of environment. Even then, Earth 32 has a different year length.

* It's an aversion if the human characters have to wear space suits (or at least respirators) when on the surface, as with LV-426 in ''Film/{{Alien}}''. However, the [[Film/{{Aliens}} sequel]] plays it straight; this is handwaved by having a terraforming station having been set up on the planet since the events of the first film.

* Creator/IsaacAsimov's ''Literature/TheEarlyAsimov'': Dr Asimov [[DiscussedTrope discusses]] the way he was [[FollowTheLeader influenced]] by the other pulp magazines to include several earthlike worlds when he was writing "Literature/TheCallistanMenace". He claims to have known that it was improbable to the extreme even then.

* In ''Anime/DragonBallZ'', someone steps blithely out onto the surface of an alien world without even bothering to test the atmosphere, and is chastised for it. In fairness though, those someones tend to be Saiyans, half-Saiyans, a Namek, androids and so on -- Krillin is the only human. Pretty much all the main characters possess an array of superpowers too, and they only spend a prolonged time on two alien worlds in canon - Namek (which, since there are at least two Namekians living on Earth, presumably has a similar atmosphere) and King Kai's planet, which has some connection to the Afterlife, so atmosphere shouldn't really be a problem.

* ''Anime/CowboyBebop'' dodges the bullet when it comes to climate because every single solid object in the Solar System has been terraformed to one degree or another. What doesn't make sense is the gravity, which is Earth-like in every inhabitable space. The main cast grew up on three different planets/moons with wildly varying gravity (Faye and Ed from Earth, Spike from Mars, and Jet from the Jovian moon Ganymede[[note]]Mars and Ganymede have 38% and 15% of Earth's gravity[[/note]]), but there's no signs of it affecting their physical growth, their living space has a single simulated gravity, and none have trouble acclimating when they move between planets.
* ''Anime/GargantiaOnTheVerdurousPlanet'' outright inverts this. No one had found any habitable planets after Earth, and ''it'' is [[EarthThatWas believed to have frozen over]].
* In ''Anime/LegendOfGalacticHeroes'', all planets shown in the series could be mistaken for locations in Earth, with those of one faction more thematically attuned to 19th Century Germany.

* {{Justified}} in ''ComicBook/MickeyMouseFrontierChronicles'', as it's mostly set on [[NumberedHomeworld Earth 32]], a human colony so similar to Earth it was named after it as they do with their colonies closer to Earth in terms of environment. Even then, Earth 32 has a different year length.

* It's an aversion if the human characters have to wear space suits (or at least respirators) when on the surface, as with LV-426 in ''Film/{{Alien}}''. However the [[Film/{{Aliens}} sequel]] plays it straight; this is handwaved by having a terraforming station having been set up on the planet since the events of the first film.
* And in ''Film/{{Avatar}}''. The atmosphere has plenty of oxygen, it's just that we can't breathe the atmosphere because the composition of the ''other'' elements in the atmosphere more resembles the Earth ''during the Permian extinction'' - a whopping ''18% carbon dioxide''; trying to breathe that is like trying to breathe with a plastic bag over your head, and 0.1% hydrogen sulfide, which is extremely toxic to humans at even ''half'' that amount, being capable of damaging the mucous linings in the lungs. The Na'vi, along with every other land animal, are able to breathe in this environment despite it being hostile to the vast majority of earth-like life because the Pandoran life actually evolved there. Additionally, just about every plant or animal is inedible/toxic to humans. The low gravity is also why everything is so much ''bigger'' on Pandora; it can afford to be, on account of the lower gravity.

* [[LampshadeHanging Lampshaded]] in ''Film/GalaxyQuest''. When a character opens a shuttle door, another character points out that they don't know anything about the planet. Fortunately, there was indeed breathable air....

** Mustafar is the only notable aversion in the movies. It's a volcanic planet with an atmosphere choked in ash. The Separatist facility seen has a forcefield keeping the air breathable, and everyone seen outside of it is either a Mustafarian, a Force user or wearing a helmet or breathing mask.
** Coruscant, despite being far closer to the center of its galaxy than Earth is to the center of the Milky Way and having three moons, is nonetheless ''identical'' to Earth in atmosphere, mass, diameter, rotational period and orbital period. Maybe it even has the same continents as Earth, if you can actually find them underneath [[CityPlanet the enormous cityscape that literally covers the entire planet]].

** Not mentioned in the films, but mentioned in the EU, Kashyyyk and the forest moon of Endor are said to have quite a bit lower gravity than standard. Hence the incredible size of some of the flora and fauna. And the fact that the Ewoks' primitive gliders are capable of flying, whereas on Earth they would never generate enough lift.

* Averted hard by E.E. Smith's ''Lensman'' and ''Skylark'' series. Intelligent life is found on all sorts of worlds, from red dwarf stars to environments at temperatures as low as one degree above absolute zero.

* Played with in the ''Literature/{{Antares}}'' series: most star systems resemble Sol, with a single habitable planet. There are no named uninhabitable solid planets. However, it is implied that just like Sol, there are a number of uninhabitable solid planets in most systems - New Providence, for instance, is identified as the seventh planet in the Napier system. Presumably, the other planets are [[TheLawOfConservationOfDetail simply unimportant]].

* ''Literature/FallenDragon'', by Creator/PeterFHamilton, averts this trope as well. Pretty much ''no'' planet is completely suited for human life. For all of them, extensive terraforming is required before sending in the colonists. Amethi was a frozen world with very little atmosphere when the first settlers came, and a scene depicts the startled reactions of a bunch of children who see ''a cloud'' for the first time. On Thallspring the soil bacteria and other biota make it necessary for the MegaCorp running the colonization efforts to clear out all life in large swaths of land via periodic [[DeathFromAbove orbital]] [[DeathRay gamma laser]] "soaks", in preparation for colony expansion. The process is stated to kill all bacteria down to a few meters underground. Santa Chico has a ''very'' high oxygen content, and its biosphere is a biochemical and medical ''goldmine'', which is why the colonists modified ''themselves'' to adapt and eventually began using OrganicTechnology, only to revert to a agrarian society of [[BodyHorror bizarre]] xenophobic [[UsefulNotes/FurryFandom Furries]] once they grew bored with the {{Mega Corp}}s periodically plundering their planet.
* In Jack Chalker's "Four Lords of the Diamond" novels humanity discovers a solar system with ''four'' Earthlike planets - completely unheard of. It's only at the end of the series that they discover that [[spoiler: the four planets were artificially constructed by an alien race as nurseries for their young.]]

* Confirmed and subverted in the ''Literature/PerryRhodan'' series. The Milky Way – rather the whole universe – is full of Earth-like planets, often to be settled by Terran or related colonists. But it's also full of hot and heavy planets suitable for hydrogen-breathers, though oxygens-breathers and hydrogen-breathers rarely interact in day-to-day life. Also, many of of the earth-like planets have extreme environments, requiring genetic modification from the settlers. Though there are hundreds of heavy-gravity worlds with extreme climates that are being settled „naturally“ by one offshoot of humanity, whose ancestors got mofidicated once.
* Averted in Creator/AlastairReynolds's ''[[Literature/RevelationSpaceSeries Revelation Space]]'' universe. Most planets are barely habitable and human inhabitants require bases with constant life support to survive. The only planets with breathable atmospheres tend to be the Juggler waterworlds, which have oxygen atmospheres. By far the only really Earth-like planet is Sky's Edge, which has a breathable atmosphere and didn't even require much {{terraform}}ing, but it's native life is [[AvertedTrope inedible]] [[NoBiochemicalBarriers to humans]], there are no analogues of vertebrate animals, a lot of the fauna [[EverythingTryingToKillYou is pretty nasty and dangerous]] and even the history of the planet's colonization is far from idyllic. [[spoiler:Also, Resurgam was once a very earthlike planet - until the local civilization of avian humanoids got wiped out during a mysterious cataclysm]].

* Forthorthe in ''LightNovel/InvadersOfTheRokujyouma'' is largely identical to Earth. Humans can eat its food, drink its water and breathe its air without a problem (and Forthortheans can do the same on Earth). When [[spoiler:Koutarou]] is suddenly transported there, he initially doesn't realise that he's on an alien planet. Forthorthe does have fantasy creatures like dragons, though.

* Earthlike planets in J.S.Morin's Literature/BlackOcean series take this to an extreme. Not only is the atmosphere breathable, not only is the food edible, but the very geography of the planet looks like Earth. Every earthlike does, however, feature a different dominant intelligent race based on the evolution of a specific kind of animal. Justified in that [[spoiler: the entire galaxy was set up as an experiment by beings from another level of reality.]]
* In ''Literature/ArrivalsFromTheDark'', the Orion Arm of the galaxy is divided between several galactic races, some of which have been in space for millennia, while one is known to have been star-faring for tens of thousands of years. Despite this, no race has more than a few hundred colonies. This is because habitable planets are few and far between. The Haptors have been in space for over three millennia and have about two hundred worlds. But their territory also includes thousands of systems they don't bother settling because they have no habitable planets. Humans have gotten good at terraforming barely habitable planets (after practicing on Mars), but it seems that only the Solar System has space habitats and domed cities on airless planets and moons (and only because many of those were built before humans got interstellar travel).

** In Series 10, the Twelfth Doctor and company [[Recap/DoctorWhoS36E9EmpressOfMars go to Mars]], so naturally they wear spacesuits — a new design this time.

*** DoubleSubverted in season one's "Solitude" when Sam and Jack are trapped in an ice cave. Sam gets a look at the surface outside and declares it's an ice planet and there's no way out. [[spoiler:In actual fact, they're on Earth, in Antarctica, which was a temperate zone when the Beta Gate was built there millions of years ago.]]

* ''TabletopGame/{{Space 1889}}'' Mercury, Venus, Mars and the moon can all support human life quite easily (if not necessarily comfortably), although only Mars has any sort of civilization on it — Mercury has only very basic life, such as trilobites, Venus has sentient lizardmen, although they are only at stone age level. Mars has an ancient civilization based around their canals, although they have lost the technology necessary to build new canals or even to maintain their cities. The Moon can also support life, although there is no atmosphere on the surface — it only exists nearer to the Moon's core.

* In ''TabletopGame/BattleTech'', 'Earthlike' is variable. No planet is exactly like Earth in terms of comfort for humans, which is commented on by those who are lucky enough actually travel there. Most of the settled worlds are fairly close, though there are wild exceptions, like the [[DomedHometown domed cities of Sirius V]] (the atmosphere is poisonous), or Tharkad, the Lyran capital, which is in a serious Ice Age (though contrary to persistant fan rumor, it is ''not'' completely frozen and does have an equatorial tropical band, something the writers take pains in pointing out on multiple occasions). [[JustifiedTrope Justified]] in that Humans would naturally pick the Earth-like planets to settle first.
** The Star League in its heyday did in fact do rather a lot of terraforming and other mega-engineering projects. Then the Succession Wars started and military budgets took priority over such expensive flights of fancy and massive terraforming projects stopped.

* Spherus Magna in ''Toys/{{Bionicle}}''. When [[EarthShatteringKaboom The Shattering]] happened, it was divided into three {{SingleBiomePlanet}}s — one jungle, one mostly desert, one ocean. Although it's fair to assume not all inhabitants survived the event, most species retained a breeding population, and were able to function on the new planets with no apparent alterations to the atmosphere or gravity. Furthermore, two of these "planets" are actually moons of the bigger planet, yet the inhabitants didn't seem to suffer from a 28-day long day-night cycle. Then when Spherus Magna was restored to its Earthlike state, there was no mention of increased gravity whatsoever.[[/folder]]

* Averted and played straight in ''VideoGame/SimEarth''. Depending on the player actions, the planet could be just like Earth, or something else altogether. Life that evolves on the planet will be Earth-like however.
* In the old ''Franchise/StarTrek'' game for the NES, players could technically ''only'' land on planets with breathable atmospheres, but all that it actually meant is that the designers only made planets with oxygenated atmospheres. The rest are just there as a backdrop.

* ''VideoGame/{{Meteos}}'' averts this trope. There is only one Earth-like planet in the game; every other planet is pretty much unique and un-Earth-like in its [[SingleBiomePlanet own]] [[PlanetofHats ways.]] Some of these are not even planets at all. Intelligent life, in this series, have sprung up on dwarf planets, asteroid clusters, dimensional rifts, interstellar gas clouds, neutron stars, and even mythological realms.

* ''VideoGame/SpaceQuestIIIThePiratesOfPestulon'' sort of averts this with the Planet Ortega, which while the atmosphere is breathable, the surface is too hot for humans who don't have special clothes.

* Subverted in ''[[VideoGame/{{Earth 2150}} Earth 2160]]''. The game takes place on a number of celestial bodies in the Solar System and around the nearby stars (one mission takes place on a very large ''comet''), but of these, only 2 planets are actually suited for human habitation. One of the is a desert planet reminiscent of the one in ''Film/{{Stargate}}'' (complete with ancient [[{{Precursors}} alien]] pyramids), while the other is a ''very'' Earthlike planet called Eden. The main characters are visibly surprised when they see a video from the surface, and some even suspect that it's actually old Earth footage.
** All of the above locations are made a bit less pleasant by the Morphidian presence.
* For most part, ''VideoGame/StarCraft'' averts this, as the vast majority of planets in the Koprulu Sector are said to be largely inhospitable to human life. In the original game, only Aiur appears to be anything close to an Earth-like planet, with most other planets supporting permanent human habitation depicted as semi-arid wastelands. [[AllThereInTheManual According to the backstory presented in the manual]], the [[SleeperShip colony ships]] were originally sent to colonize a habitable planet that was one year away from Earth, but ended up traveling blindly through space for twenty eight years when their navigation systems shut down. The supercomputer controlling the ships forced them to land on the nearest habitable planets before life support systems failed.
** Expanded universe materials and the sequel game expand the number of Earth-like planets, with Umoja, Agria, and Meinhoff being notable examples. Korhal IV also used to be a nice place to live, but most of the planet was flattened by nuclear missiles before the start of the first game.
* ''VideoGame/WarCraft'' only has three explicitly known planets, Azeroth, Draenor, and Argus, all of which are or were very earth-like. Draenor was [[WorldSundering ripped apart by magical experiments]] and [[{{Mordor}} drained of its life by demonic influence]], which makes it a very alien place... with the exception of Nagrand, which somehow remained untouched. What else is left of the planet still qualifies as earth-like as far as this trope is concerned. Life is still possible (even though half of the zones have no water or any plantlife other than herbs, but that's more an issue of GameplayAndStorySegregation). However, the alternate Draenor players visit in ''Warlords of Draenor'' is set in the past before all the aforementioned planetary corruption happened and looks perfectly normal for the most part. Argus was turned into a smoldering DeathWorld by the [[LegionsOfHell Burning Legion]] before being made into their central base planet, but flashbacks in ''Legion'' show that it used to be just as earth-like as Azeroth and Draenor.
* The Lunarian Moon (no, that's not redundant) in ''VideoGame/FinalFantasyIV'' has a perfectly breathable atmosphere and its gravity is identical to the heroes' homeworld. Just ignore the man-sized viruses and the killer plates of flan.
* Invoked in ''VideoGame/UltimaUnderworld II'', when Iolo expresses concern that one of the facets of the gem might transport you to a planet of poisonous gas or an ocean floor.
* Averted in ''VideoGame/SidMeiersAlphaCentauri''--Planet is called "earthlike" at the very beginning, yet some of the many problems you face in the course of colonizing Planet are the poisonous atmosphere (90% nitrogen rather than 78%, combining with higher gravity and a thicker atmosphere to give you [[http://en.wikipedia.org/wiki/Nitrogen_narcosis nitrogen narcosis]] if you try to breathe it), [[NoBiochemicalBarriers inedible plantlife]], and hostile ([[GaiasVengeance very, very hostile]]) native fauna. And the game doesn't hide the fact that even such "earthlike" planets are very rare.

* The ''VideoGame/EscapeVelocity'' games feature all kinds of planets, including gas giants. The most you'll ever see of one, though, is a little pre-rendered image. Many of the ones that you can actually interact with are habitable for one or another reason.
* While most human systems are inhabited in one way or another in ''VideoGame/EndlessSky'', this trope is subverted, as most colonised planets are lacking in one way or another (high tectonic activity, frigid temperatures). Additionally, amongst the planets that are Earth-like, most have had to be {{Terraform}}ed in one way or another.
* ''VideoGame/StarControl 2'' averts this trope: it has at least 50 ''types'' of planets. The kinds that support (humanoid) life are rare; many--not all--races come from home planets of these types (and among them (water worlds as are known there) are included those with temperatures so high that lack oceans as well as those so cold their water is frozen). Each type has common characteristics--likely minerals, ranges of size and strength of gravity, tectonics, and so on. All but gas giants can be landed on and explored via Lander vehicles.
* ''VideoGame/GalacticCivilizations II'', with all of its expansions in, finally adds toxic, ocean, high grav, barren and other world types. However, you can research technologies to colonise all of them.
** Except possibly on the highest "usable worlds" setting, nearly all of the worlds you encounter are not only not earthlike but completely uninhabitable quality 0 gas giants or tiny balls of scorched or frozen rock. Although there are weird mega-events that occasionally roll through and turn an entire system into medium to high quality potential colonies, regardless of the size or nature of the planets.
* ''VideoGame/StarOceanTillTheEndOfTime'' is guilty. Although there are a variety of planets not suitable for humans to live on (or those where it'd be very difficult for them to thrive), the main party always conveniently lands on one where they can breathe the air and move around comfortably despite any effects of the gravitational fields.
** [[spoiler: [[AWizardDidIt The 4D beings designed things that way]].]]
* Subverted in the ''Franchise/{{Halo}}'' series. It's revealed in the expanded universe that it often takes ''decades'' of terraforming to make a colony world suitable for human use. There's also an outright aversion in the Grunt homeworld, which has a methane atmosphere. That said, there are plenty of planets that play this fairly straight too, even if they have an extra moon/sun or two.

* Averted in ''VideoGame/StarRuler'' where some planets have a charred appearance and are clearly not Earthlike.

* Averted in the ''[[VideoGame/{{X}} X-Universe]]''. There ''are'' a fair number of Earthlike planets (most of which are colonized by the [[HumansByAnyOtherName Argon]]), but plenty are decidedly not Earthlike and still inhabited. The Boron homeworld Nishala is an ocean planet with an ammonia atmosphere, and the Terrans' LostColony Aldrin is an airless planetoid that presumably uses pressure domes or the equivalent. The Terrans also have settlements on several objects in the Sol System other than Earth. And that's before you get into the many planets that are absolute uninhabitable hellholes covered in lava flows or what-have-you.
* While ''VideoGame/EndlessSpace'' probably has more Earth-like planets than would be possible in RealLife, there are also a lot more planets that are inhospitable, although colonization is possible after extensive research. Even terraforming may be possible closer to the end of that research branch, although gas giants and asteroid belts (which can also be colonized) can never be turned into hospitable planets.
* The Beta Caeli system in ''VideoGame/AlienLegacy'' has not one but ''two'' Earth-like planets, named after the Greek goddesses/Titanesses Rhea (mother of the gods) and Gaea (earth goddess). Gaea is the third planet like Earth but lacks a satellite. Despite this, it has plant and animal life, even though it would be difficult for them to evolve without tides. Rhea is the second planet like Venus but has the same conditions and even life forms as Gaea. The game implies the presence of a Moon-sized satellite prevented a Venus-like greenhouse effect. The rest of the planets are similar to Solar System planets. All planets (including satellites and asteroids) except for gas giants are colonizable. However, the late-game reveal that [[spoiler:the two habitable planets were seeded by the [[AbusivePrecursors H'riak]]]] may imply that this is not a natural occurance. The existence of the Centaurians also implies a habitable planet in the Alpha Centauri system, although whether it's habitable for ''humans'' is anyone's guess, as [[InscrutableAliens nothing is known about the Centaurians]] except that they're AbsoluteXenophobes.
* {{Averted|Trope}} in ''VideoGame/NoMansSky''. Within the planets you can explore, many of the planets players will encounter will be lifeless rocks, only 10% of them will have life on them, and only 10% of ''those'' worlds will be flourishing, earthlike "garden"-type worlds. That doesn't necessarily mean that the non-earthlike worlds (or barely earthlike worlds) will be useless, though: a barren world may have more valuable resources in it than an earthlike world.
* Played with in ''VideoGame/TheMandate'' as the Osmani faction had the unfortunate luck of having their colony ship land are a very hazardous world. This forced them to become cyborgs in order to survive.
* {{Averted}} in ''{{VideoGame/Outpost}}''. [[spoiler: No star has an Earth-like planet in that game, at least until you develop terraforming and the friendliest one are those that are Mars with the SerialNumbersFiledOff]], with planets there being identical to RealLife Solar System bodies (including even two moons and two [[ScienceMarchesOn minor planets]]) in everything but surface features. The game's demo showed different planets, but it was one of the features missing on it (see entry for ''VideoGame/{{Outpost2}}'' for more.)

* ''VideoGame/{{Stars}}'' averts the trope. Part of defining an alien race is specifying its ideal and habitable range for temperature, gravity, and radiation, which determines which planets your colonists can survive or thrive on.
* Mostly averted in ''VideoGame/KerbalSpaceProgram''--since it's based on the real solar system, only the third planet from the sun, "Kerbin," is Earth-like. The rest of the planets and moons are lifeless, and many don't even have atmospheres. However, Laythe, one of the gas giant's moons, conveniently has oxygen [[ArtisticLicenseChemistry (which can only exist in a planet's air for long periods if it's constantly replenished by plant life)]] so that jet engines will function.
* In ''Videogame/{{Destiny}}'':
** Most of the planets you can visit in the solar system are relatively Earth-like (in that humans can walk around on them and breathe the atmosphere) but this was due to [[SufficientlyAdvancedAlien the Traveler]] going around and {{terraform}}ing them.Venus, Mars, Io, and Titan, for example, are all inhabitable by humans, while Earth's Moon has at least some atmosphere. That said, each planet retains features from before its conversion. For example, [[http://www.gamersheroes.com/wp-content/uploads/2014/09/Destiny-Hunter.jpg Venus]] is still a yellow planet with a thick atmosphere and strange weather patterns, but now it can support vast jungles and human cities. [[https://www.bungie.net/img/theme/destiny/bgs/pgcrs/patrol_mars.jpg Mars]] remains a red, sandy desert, but it's atmosphere is warm enough, thick enough, and breathable enough for humans. [[http://images.eurogamer.net/2017/metabomb/ioscreenshot3.jpg Io]], despite being a tiny moon, was turned into a verdant green Earth-like world.
** [[http://1.bp.blogspot.com/-qfgcwvpJCDA/VIuTZTy8s6I/AAAAAAAAA9Y/7j4YSqFL2iw/s1600/db_destiny_129.jpg Mercury]] was ''intended'' to be a very Earth-like world by the Traveler, but [[MechanicalLifeforms the Vex]] came along and [[HostileTerraforming converted the entire planet into a vast Vex machine]]. And while [[https://assets.vg247.com/current//2017/05/destiny_2_environments-6.jpg 7066 Nessus]] ''looks'' Earth-like, only with red vegetation instead of green, the entire planet is another Vex machine world and it has an atmosphere intensely toxic to humans.
* In ''VideoGame/{{Rimworld}}'', all the procedurally generated planets are suggested to have been terraformed and seeded with Earth lifeforms (though some are genetically modified) at some point long before your settlers crashland on them. Also, [[AnthropicPrinciple crashlanding on an airless rock would make for a really short and uninteresting game]]. The game averts SingleBiomePlanet (though there are apparently plans to implement them in future builds) as there are a number of biomes to play in: a band of Temperate Forest[[note]]fertile deciduous forest with pleasant summers and cold winters, plentiful flora and fauna and comfortable living[[/note]] runs across the northern hemisphere, giving way to Arid Scrubland[[note]]sun-baked grassland with the odd scattered grove, hot summers and cool winters, plants and animals here are hardy and your settlers will have to be too[[/note]], Desert[[note]]extremely dry and hot with little sign of life anywhere, scorching summers and cold winters, arable soil is difficult to find[[/note]] and Tropical Jungle[[note]]thick and moist jungle filled with dangerous animals and disease, very hot summers and winter isn't much better[[/note]] in the south, and Boreal Forest[[note]]brooding forests of coniferous trees, very cold winters but summers can be pleasantly warm, growing season is quite short so make it count[[/note]], Tundra[[note]]snow-coatedd plains home to large herds of migratory grazers and little else, very cool summers and freezing winters, growing crops here may be impossible without hydroponics[[/note]] and Ice Sheet[[note]]arctic conditions with permafrost kilometres thick in places, below freezing practically all year round, most food must come from hunting, trade or [[NoPartyLikeADonnerParty cannibalism]][[/note]] in the north.
* Averted in ''VideoGame/OdysseusKosmosAndHisRobotQuest''. There are only two planets of note in the Gargan-Hope [[BinarySuns binary system]]: Calcutta and Ithaca. Ithaca is an ice-covered lifeless rock, with the "ice" actually being composed of inert gases, not water. The surface temperature is only about 30 degrees above absolute zero. Calcutta is a super-Earth about 1.5 times the size of our planet. The average surface temperature is zero Celsius, and yet there's liquid water on the surface, which is probably the only reason the crew went down to investigate. Since Calcutta is close to Gargan, it experiences a lot of TimeDilation, to the point where minutes on the surface translate into years aboard the ship.

* ''Webcomic/RoninGalaxy'': Just another average day in Japa- Whoa! Those are some huge potholes. [[http://www.roningalaxy.com/comic/1-2/ That look suspiciously like Moon craters....]]
* In the "GOFOTRON" arc of ''Webcomic/SluggyFreelance'', the cast visits the Punyverse, AnotherDimension consisting of about one hundred planets, all but a few of them inhabited, and packed together within easy traveling distance. The strip actually [[LampshadeHanging addresses the oddness]] of this, with Riff saying, "I've never seen a universe so ... deliberate." [[spoiler:Later [[JustifiedTrope justified]] when it's revealed that the Punyverse did not evolve naturally, but was actually created for an alien science project.]]
* ''Webcomic/{{Earthsong}}'' justifies this one fairly well - all the aliens encountered are from Earthlike planets for the simple reason that planets must make themselves Earthlike before they are given the secret of supporting life.

* In the '90s ''WesternAnimation/XMen'' cartoon, a passing Shiar ship was bored that they had to map out a section of the universe filled with uninhabited worlds. This was the section that Dark Phoenix fried. Note, this is more of a case of softening her FaceHeelTurn, as in the original comics she ''did'' destroy inhabited worlds; and some people consider that unforgivable.

* In ''WesternAnimation/{{Futurama}}'', the only non-Earthlike planets shown so far are a few moons and asteroids without atmospheres, and one high-gravity (but otherwise Earthlike) planet. Even the world with [[AlienSky three giant suns]], apart from being a bit warm at full noon, was perfectly livable to humans.

* Averted in ''WesternAnimation/RoughnecksStarshipTroopersChronicles'', on Pluto, Hydora, Tophet, Zephyr, and Klendathu the Roughnecks need to wear pressurized suits, the only planets with shirtsleeve environments are Earth and Tesca. And T'Phai, a Tophet native who joins the squad after that campaign, needs to wear his own pressure suit off his homeworld.

* [[https://en.wikipedia.org/wiki/Rare_Earth_hypothesis The Rare Earth hypothesis]] exists for a reason - because we haven't found an abundance of worlds exactly like our own yet. Heck, we haven't even found a Solar System that's anything like ours yet. This is a plausible explanation to the Fermi paradox for [[AbsentAliens why we've not found any extraterrestrial civilizations]]. Spare a thought for astronomers [[NeedleInAStackOfNeedles working tirelessly to find one]].

** And on December 2011 scientists announced that Kepler found [[http://news.cnet.com/8301-19514_3-57337039-239/earth-like-planet-found-in-distant-suns-habitable-zone/ Kepler-22b, a world twice the size of Earth]] and parked well within the "Goldilocks" orbit that would allow for water to exist in liquid form (meaning it could generate carbon-based life similar to our own). Even better, the [[https://en.wikipedia.org/wiki/Kepler-62 Kepler-62 system]] announced in April 2013 has ''two'' planets around 50% larger than Earth within the habitable zone. Unfortunately, Kepler-22b's mass is still unknown - it could be just below 52.8 Earth masses, making it a "mini-Neptune" and such celestial bodies are not promising abodes for life. We have the same problem with Kepler-62e and f. The estimates range between 35 and 36 Earth masses, not Earth-like in the strictest sense, so they're less-than-ideal candidates for life.[[note]]These are ''upper'' masses, which are considered unrealistic due to the high densities those planets would have. While it's generally now assumed that Kepler-22b is a small version of Neptune, perhaps one or even the two worlds of Kepler-62 would be luckier.[[/note]].

* Despite all the science and fact-based theories out there, the fact of the matter is we will never be able to conclusively pin down how much a planet can differ from Earth itself and still stay Earth-like (for instance, ratio of ocean to land - most of our oxygen comes from the ocean), until we actually find Earth-like worlds to compare (or terraform our own). This is not to say that our theories aren't good science, they are. We just don't have any real-life examples to closely analyze to compare results yet, and there are always surprises ahead no matter how well-checked your math is.

** Coruscant, despite being far closer to the center of its galaxy than Earth is to the center of the Milky Way and having three moons, is nonetheless ''identical'' to Earth in atmosphere, mass, diameter, rotational period and orbital period. Maybe it even has the same continents as Earth, if you can actually find them underneath the enormous cityscape that literally covers the entire planet.

** It's not most definitely not a normal planet, but while the belly of the gigantic space slug in ''Film/TheEmpireStrikesBack'' lacks a breathable atmosphere, it apparently has normal gravity and pressure. Odd, as it's ''inside an asteroid in deep space''. Maybe the ''Millennium Falcon'' was able to extend its artificial gravity field or the asteroid field as a whole had some kind of atmosphere.

** Not mentioned in the films, but mentioned in the EU, Kashyyyk and the moon of Endor are said to have quite a bit lower gravity than standard. Hence the incredible size of some of the flora and fauna. And the fact that the Ewoks' primitive gliders are capable of flying, whereas on Earth they would never generate enough lift.

* Averted in ''Literature/ChildhoodsEnd'': The Overlords come from a world whose gravity is weaker than Earth's. Also, before the Overlords show themselves to humanity, one human character points out that as far as any human knows, the Overlords might breathe chlorine.

* ''Literature/TheCosmere'': All planets we've seen can support human life. While most of these planets have god-like [[PiecesOfGod Shards]] who either explicitly or implicitly terraformed the planet, there are also worlds without Shards that are still very close to Earth normal. Per WordOfGod, [[Franchise/{{Mistborn}} Scadrial]] is a direct parallel to Earth, with identical time, environment, gravity, ecology (not counting when it was [[AfterTheEnd the World of Ash]]), and even [[FantasyCounterpartCulture culture]]. On the other hand, ''Literature/TheStormlightArchive'''s Roshar is only able to support human life in the most liberal sense of the word. Years are five hundred days long (but the days are shorter so the year only ends up ten percent longer than Earth normal), gravity is seventy percent of normal, oxygen content in the atmosphere is a bit higher, most of the animals are some variety of arthropod, the plants look like things you'd find underwater, and world-breaking highstorms blow from east to west every few days.

* ''{{ComicBook/Watchmen}}'' has a single superhuman in the world, Dr. Manhattan. He teleported to Mars just to have some solitude (with his godlike powers, he has absolutely no problem to survive there), and later returned and teleported Laurie to Mars as well. But, being a normal human, Laurie almost died of suffocation in Mars, before Dr. Manhattan remembered that other people need to breathe and created an air bubble for her.

** Averted in ''Series/StarTrekVoyager'' episode "Demon". A class-Y planet is colloquially known as a 'Demon' class planet because it's as harsh as the class-N Venus.

* Forthorthe in ''LightNovel/RokujyoumaNoShinryakusha'' is largely identical to Earth. Humans can eat its food, drink its water and breathe its air without a problem (and Forthortheans can do the same on Earth). When [[spoiler:Koutarou]] is suddenly transported there, he initially doesn't realise that he's on an alien planet. Forthorthe does have fantasy creatures like dragons, though.

* Although not an exact example, the discovery of Zarmina (aka Gliese 581 g), the first extrasolar planet potentially capable of supporting Earth-like life, after just under twenty years of searching has some scientists convinced that Earth-like planets are actually pretty common.
** [[SubvertedTrope Subverted]] in that while it could possibly (we don't know for sure yet) support Earth-like life, it's still ''very'' different from Earth. Just for a start, the planet is tidally locked around its red dwarf sun, meaning that one side is always facing the sun while the other is in perpetual darkness. This means that the only habitable zone is the terminator, where it would be an unending dusk/twilight. Most likely a region of never-ending storms as the two extreme climates meet. Furthermore, the surface gravity is significantly higher (1.5 g is the current estimate), although still within a (relatively) comfortable range.
** Gliese 581 g's existence has been called into question. Other teams examining the system have been unable to confirm its orbit. That said, the presence of planets potentially like Gliese 581 g has some interesting ramifications for the type of habitable worlds possibly present in the universe. If it's common for larger red dwarfs to have planets like that, then the ''majority'' of habitable planets may be those orbiting red dwarfs (since they vastly outnumber more luminous stars).

** Enter [[https://en.wikipedia.org/wiki/Kepler-186f Kepler-186f]], [[https://en.wikipedia.org/wiki/Kepler-438b Kepler-438b]], and [[https://en.wikipedia.org/wiki/Kepler-442b Kepler-442b]], a trio of worlds announced in March 2014 and January 2015 respectively, very similar in size to Earth and that orbit stars smaller than the Sun within their habitable zones. However, 186f and 438b are probably being bombarded with extreme ultraviolet (XUV) fluxes, violent stellar flares, and powerful radiation activity from their red dwarf parent stars every 100 days. Disregarding the tidal locking problems, were you to swap Earth with either of them, our poor biosphere would be sterilized. 442b is a "Super-Earth" which, again, we don't know much about. It could be a LethalLavaLand or a mini-Neptune like body.

** Then there's the ''seven'' potentially Earth-like planets of the faint star [[https://en.wikipedia.org/wiki/TRAPPIST-1#Planetary_system TRAPPIST-1]]. But these may also be subject to solar flares, and [[https://en.wikipedia.org/wiki/TRAPPIST-1b two]] [[https://en.wikipedia.org/wiki/TRAPPIST-1c of]] them are ''[[DeathWorld nasty]]'' places (b being much worse than Venus), [[https://en.wikipedia.org/wiki/TRAPPIST-1h anoother]] is probably too cold to support liquid water, and of the four remaining, [[https://en.wikipedia.org/wiki/TRAPPIST-1f another]] is likely to be a hot pressure-cooker world like b.

* ''ComicBook/WonderWoman1942'': Diana visits just about every planet in the solar system, all of which prove earth like with a breathable atmosphere. As does the moon, which even has a forest on it.

** In ''VideoGame/MassEffect2'', most of the planets you visit are at least partially Earthlike. Key word being ''visit'': you only ever touch down on planets with some kind of habitation, even if it's just a tiny mercenary resupply point. Also, the Blood Pack have a base set up on a world that's filled with gas that's toxic to all your crew members but the Vorcha can live there fine.
** ''VideoGame/MassEffectAndromeda'' is basically about the main character trying to find an actual Earth-like planet for galactic colonization, after all the scanned "Golden Worlds", supposedly Earth-like planets, turned out to be [[DeathWorld Death Worlds]]. [[spoiler:Later on in the game, the earthlike-ness turns out to have been because a group of sufficiently advanced aliens went to a lot of trouble to make them nice and cosy for their own ends.]]

*** And then, there are those examples where Planets are absurdly ''present-day'' Earth-like to the point where Ikea furniture would fit right in. Particularly common in later seasons and "Atlantis".

* The impact that even minor differences from Earth that apparently habitable alien planets have becomes a major plot point in the ''TabletopGame/{{Warhammer 40000}}'' fanfic ''[[FanFic/Warhammer40000TheMisfits The Misfits]]''. The planets of the Storm Ravens chapter's home system, Octalia, contain extremely low levels of potassium, so the government needs to import supplements from other star systems. This allows the BigBad to incite a revolt by exposing the fact that the government has been skimming from the supplement fund and allowing the lower classes to suffer potassium deficiency.

** And on December 2011 scientists announced that Kepler found [[http://news.cnet.com/8301-19514_3-57337039-239/earth-like-planet-found-in-distant-suns-habitable-zone/ Kepler-22b, a world twice the size of Earth]] and parked well within the "Goldilocks" orbit that would allow for water to exist in liquid form (meaning it could generate carbon-based life similar to our own). Even better, the [[https://en.wikipedia.org/wiki/Kepler-62 Kepler-62 system]] announced in April 2013 has ''two'' planets around 50% larger than Earth within the habitable zone.
*** Unfortunately, Kepler-22b's mass is still unknown - it could be just below 52.8 Earth masses, making it a "mini-Neptune" and such celestial bodies are not promising abodes for life. We have the same problem with Kepler-62e and f. The estimates range between 35 and 36 Earth masses, not Earth-like in the strictest sense so less than ideal candidates in our search[[note]]These are ''upper'' masses, which are considered unrealistic due to the high densities those planets would have. While is generally now assumed that Kepler-22b is a small version of Neptune, perhaps one or even the two worlds of Kepler-62 would be luckier[[/note]].
** Enter [[https://en.wikipedia.org/wiki/Kepler-186f Kepler-186f]], [[https://en.wikipedia.org/wiki/Kepler-438b Kepler-438b]], and [[https://en.wikipedia.org/wiki/Kepler-442b Kepler-442b]] a trio of worlds announced in March 2014 and January 2015 respectively, very similar in size to Earth and that orbit stars smaller than the Sun within their habitable zones. And, last but not least, meet orbiting within Proxima Centauri's, the closest star to the Sun, habitable zone the Earth-like [[https://en.wikipedia.org/wiki/Proxima_Centauri_b Proxima Centauri b]] that was discovered in August 2016 and the ''seven'' also quite Earth-like planets of the faint star [[https://en.wikipedia.org/wiki/TRAPPIST-1#Planetary_system TRAPPIST-1]].
*** Sadly another subversion. 186f and 438b are being bombarded with extreme ultraviolet (XUV) fluxes, violent stellar flares, and powerful radiation activity from their Red Dwarf parent star every 100 days. Disregarding the tidal locking problems, were you to swap Earth with either of them, our poor biosphere would be sterilized. 442b is a "Super-Earth" which again, we don't know much about. It could be a LethalLavaLand or a mini-Neptune like body, and Proxima Centauri b suffers something similar to 186f and 438b. As for the seven planets of TRAPPIST-1, not only they may have been flared as the previous examples but also [[https://en.wikipedia.org/wiki/TRAPPIST-1b two]] [[https://en.wikipedia.org/wiki/TRAPPIST-1c of]] them are ''[[DeathWorld nasty]]'' places, b being much worse than Venus, [[https://en.wikipedia.org/wiki/TRAPPIST-1h other]] is likely too cold to support liquid water, and of the four remaining [[https://en.wikipedia.org/wiki/TRAPPIST-1f another]] at least is like b basically a searing hot pressure-cooker world
** It's very important to bear in mind that in all the above examples we can only say with our current technology that ''there is'' in orbit around those stars a planet (or several of them) that is Earth-like in terms of diameter and/or mass as well as stellar flux received. Besides at best in some cases rudimentary data on their atmospheres as with some of the worlds of the TRAPPIST-1 system, we just can guess how they're with theoretical models and we do not know how actually ''are'' those planets: if places like Earth, bodies [[DeathWorld even worse than Venus]], worlds with liquid water... but everything else nasty for humans, Mars-like barren worlds whose atmosphere were stripped away by the stellar winds, truly exotic places that would seem to have escaped of a science-fiction work, or anything in between.