History Main / AllPlanetsAreEarthLike

*** 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 36 and 35 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]].

*** 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, and 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

* 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.

** ''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]].

* Likewise, all the inhabited worlds in ''Series/{{Firefly}}'' were deliberately {{terraform}}ed, though they each have their little quirks.

* ''Literature/{{Coyote}}'': The the earth-sized moon of the gas giant in habitable orbit around 47 Ursae Majoris isn't exactly an "all planets Earth-like" occurence (but instead an Earthlike world is supposedly discovered there before the mission is sent, and at 46 light years away there are hundreds of stars that would be closer that wouldn't have such planets, given that this is the first mission of its kind sent from Earth and so we could presume it's the closest); so mainly averted. However, even though such a world could be spectrally-analyzed from a distance with sensitive enough equipment to ensure its atmosphere's chemical content, and gravity inferred through mass (from its orbit) and imaging of the body, there was still the risk that the indigenous life there would be of right-handed chirality rather than left-handed (as Earth life is), which would mean none of it would be consumable to the settlers. This was the first "moment of truth" once the humans landed there--but the biologists confirmed that luckily, the life was left-handed chirality as well. It is unsure whether the chance of this is really 50/50 as seemingly implied though, as we don't yet have samples of any extraterrestrial life ([[ConspiracyTheory at least widely known]]) yet, let alone a widespread variety to statistically analyze.

* ''Literature/{{Coyote}}'': The the earth-sized moon of the gas giant in habitable orbit around 47 Ursae Majoris isn't exactly an "all planets Earth-like" occurence (but instead an Earthlike world is supposedly discovered there before the mission is sent, and at 46 light years away there are hundreds of stars that would be closer that wouldn't have such planets, given that this is the first mission of its kind sent from Earth); so mainly averted. However, even though such a world could be spectrally-analyzed from a distance with sensitive enough equipment to ensure its atmosphere's chemical content, and gravity inferred through mass (from its orbit) and imaging of the body, there was still the risk that the indigenous life there would be of right-handed chirality rather than left-handed (as Earth life is), which would mean none of it would be consumable to the settlers. This was the first "moment of truth" once the humans landed there--but the biologists confirmed that luckily, the life was left-handed chirality as well. It is unsure whether the chance of this is really 50/50 as seemingly implied though, as we don't yet have samples of any extraterrestrial life ([[ConspiracyTheory at least widely known]]) yet, let alone a widespread variety to statistically analyze.

* ''Literature/{{Coyote}}'': The the earth-sized moon of the gas giant in habitable orbit around 47 Ursae Majoris isn't exactly an "all planets Earth-like" occurence (but instead an Earthlike world is supposedly discovered there before the mission is sent, and at 46 light years away there are hundreds of stars that would be closer that wouldn't have such planets, given that this is the first mission of its kind sent from Earth); so mainly averted. However, even though such a world could be spectrally-analyzed from a distance with sensitive enough equipment to ensure its atmosphere's chemical content, and gravity inferred through mass (from its orbit) and imaging of the body, there was still the risk that the indigenous life there would be of right-handed chirality rather than left-handed (as Earth life is), which would mean none of it would be consumable to the settlers. This was the first "moment of truth" once the humans landed there--but the biologists confirmed that luckily, the life was left-handed chirality as well. It is unsure whether the chance of this is really 50/50 as seemingly implied though, as we don't yet have samples of any extraterrestrial life ([[ConspiracyTheory at least known]]) yet, let alone a widespread variety to statistically analyze.

*** 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 36 and 35 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-22 is a small version of Neptune, perhaps one or even the two worlds of Kepler-62 will be luckier[[/note]].

*** 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, and 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.

* Played straight as you'd expect with the NoBudget ''Series/BlakesSeven''. Though in fairness most planets they land on are or were human colonies, which would have been chosen for their ability to support human life. Spacesuits are only used for vacuum however, with the occasional mention of breathing masks. Thermal suits are worn for the more colder planets. There's a nice subversion of the trope in "The Harvest of Kairos". Servalan has captured our heroes and agrees that, if they hand over command authorisation of the Liberator to her, she will teleport them down to a planet with Earth-like conditions. Unfortunately the nearest such planet is Kairos, which happens to be a DeathWorld thanks to its [[TheSwarm lifeforms]].

* Played straight as you'd expect with the NoBudget ''Series/BlakesSeven''. Though in fairness most planets they land on are or were human colonies, which would have been chosen for their ability to support life. Spacesuits are only used for vacuum however, with the occasional mention of breathing masks. Thermal suits are worn for the more colder planets. There's a nice subversion of the trope in "The Harvest of Kairos". Servalan has captured our heroes and agrees that if they hand over command authorisation of the Liberator to her, she will teleport them down to a planet with Earth-like conditions. Unfortunately the nearest such planet is Kairos, which happens to be a DeathWorld thanks to its aggressive lifeforms.

* ''VideoGame/{{Stellaris}}'' does have planets that aren't inhabitable, such as gas giants, "barren worlds" (including Mars, asteroids, most moons), and toxic worlds. And inhabitable planets themselves are divided into ten types (Earth is "continental") and species favor the same type of planet they were native to, though populations can be genetically modified to favor different planet types and inhabitable planets can be terraformed.

** Hamilton's ''other'' big book series, the [[NightsDawn Night's Dawn Trilogy]], averts this trope as well, with habitable planets being classed as "Terracompatible".

* ''VideoGame/WarCraft'' only has two explicitly known planets, Azeroth and Draenor, both of which are very earth-like. However, 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).

* 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 domed cities of Sirius V (the atmosphere is poisonous. [[JustifiedTrope Justified]] in that Humans would naturally pick the Earth-like planets to settle first.

Often [[JustifiedTrope justified]] 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).

** [[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. Furthermore, the surface gravity is significantly higher (1.5 g is the current estimate), although still within a (relatively) comfortable range.

*** 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, and our poor biosphere would be sterilized. 442b is "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.

*** 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 36 and 35 Earth masses, not Earth-like in the strictest sense so less than ideal candidates in our search.

*** 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, and our poor biosphere would be sterilized. 442b is "Super-Earth" which again, we don't know much about. It could be a LethalLavaLand or a mini-Neptune like body.

** "[[http://community.fortunecity.ws/tattooine/heinlein/326/CoDominium/haven.htm Haven]]", the titular ''War World'', is pretty much a case of Pournelle getting together with Niven and asking, "[[DeathWorld Exactly how horrible can we make a planet while still letting humans breathe the air?]]"

** 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, Venus is still a yellow planet with a thick atmosphere and strange weather patterns, but now it can support vast jungles and human cities. Mars remains a red, sandy desert, but it's atmosphere is warm enough, thick enough, and breathable enough for humans. Io, despite being a tiny moon of Saturn, was turned into a verdant green Earth-like world.
** 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.

** 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, Venus is still a yellow planet with a thick atmosphere and strange weather patterns, but now it can support vast jungles and human cities. mars remains a red, sandy desert, but it's atmosphere is warm enough, thick enough, and breathable enough for humans. Io, despite being a tiny moon of Saturn, was turned into a verdant green Earth-like world.
** 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 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.

** ''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]] with the occasional precursor civilization that has an axe to grind with ''those Milky Way Space Western Nazis'', AKA you.

!!Examples

* {{Averted|Trope}} in ''VideoGame/NoMansSky''. While there's very few planets that are completely devoid of life, not many planets have ecology that can be described as Earth-like either.