%% Image kept on page per Image Pickin' thread: http://tvtropes.org/pmwiki/posts.php?discussion=1309829763045300100
%% Please do not change or remove without starting a new thread.
[[quoteright:284:[[UsefulNotes/{{NASA}} http://static.tvtropes.org/pmwiki/pub/images/solar_system_4607.gif]]]]
[[caption-width-right:284:Not quite how our solar system is arranged.]]

->'''Reggie:''' Over the past week, the planets of our solar system have moved outside their orbital paths and are coming into alignment. I mean, do you know how unusual that is? \\
'''Methos:''' But that could just be orbital wobble.
-->-- ''Film/HighlanderTheSource''

Ah, fictional astronomy. The really great thing about writing is you get to make the entire Cosmos do what you want it to, even things it can't really do. This indexes some of the shortcuts writers take related to astronomy.

These overlap ArtisticLicensePhysics and SpaceDoesNotWorkThatWay. Not to be confused with {{Astrolog|er}}y, no matter how open to interpretation the stars may be.


* AsteroidThicket
* BabyPlanet
* CounterEarth
* ConvenientlyClosePlanet
* EarthShatteringKaboom
* FlamingMeteor
* FullMoonSilhouette
* GravitySucks
* ObliviousAstronomers
* SciFiWritersHaveNoSenseOfScale
* SolarFlareDisaster
* SpaceClouds
* SpinTheEarthBackwards
* TheStarsAreGoingOut
* StarsAreSouls
* TotalEclipseOfThePlot
* UnrealisticBlackHole
* VulcanHasNoMoon
* WeirdMoon
* WeirdSun


!!Unclassified Examples

Can't figure out where to put your astronomy related example? Leave it here. When we get enough like it, a new trope will begin to form. Kind of like a solar system, if you think about it.\\


[[folder:Mangled Celestial Motion -- Relative Planetary and stellar placement]]
* This is OlderThanPrint. In ''Literature/TheDivineComedy'', Dante violates a principle of medieval astronomy, that the Sun, Mercury, and Venus were always close as they orbited Earth, in order to have Mercury and Venus appear in the shadow of the Earth. Doing so allows Dante to use [[DarkIsEvil darkness to symbolize the deficiencies of the souls of Mercury and Venus]].
* In an energy snack commercial a basketball player (Lamar Odom) shows off his ability to dunk to the Moon. On his way, he tells Saturn to get out of his way. If we're suspending our disbelief enough to buy that a guy jump to the Moon, Saturn might as well be between the Earth and the Moon. The next guy says he's going to dunk on Pluto. Okay. For all we know, that might be a shorter trip than one to the Moon, in this {{ficton}}'s astronomy.
* In ''Film/LaraCroftTombRaider'', all the planets including Pluto ([[ScienceMarchesOn which at the time, was a planet]]) are aligned. Okay. Pluto's orbit is highly erratic, tilted at an angle of 17 degrees to the ecliptic and highly eccentric (being the wrong kind of ellipse). It will probably never align closely with all the other planets in the lifespan of the solar system, but you can't have a ''really'' good planetary collection without having the whole set.
* ''Series/DoctorWho'': [[TheMovie The 1996 TV movie]] places Gallifrey, the Doctor's home planet, some 250 million light years away from Earth, on "the other side" of the Milky Way. That's about 249.9 million light years ''past the other edge of it''. The Milky Way is estimated to be only between 80 and 100 ''thousand'' light years across.
* In ''Film/JimmyNeutronBoyGenius'', Jimmy claims that the Yokian's home planet is in the Orion system, approximately 3 million light years away. The Orion system is actually only 1360 light years away at its farthest estimates, and any star that far away would have to be in a different galaxy regardless.
* Towards the end of Creator/JKRowling's ''Literature/{{Harry Potter and the Order of the Phoenix}}'', in mid or late June, Harry is taking his astronomy O.W.L. and charting Orion. Orion is not visible in the night sky in mid or late June at ''any'' latitude. The same scene also has him looking around for Venus (which is never more than 47 degrees away from the sun) around midnight. Needless to say, he didn't do particularly well on ''that'' O.W.L.. Just as well. Muggles have to be better at ''something.'' In addition, it never gets dark enough for stargazing in northern Scotland in July.
* When the aliens attempt to reach Earth in ''Fanfic/CalvinAndHobbesTheSeries'', the narrative inexplicably swaps Jupiter and Saturn's positions in the solar system.
* In ''Series/{{Firefly}}'', the 'Verse is set in a quintiple star system that was reached and settled by 2517 via GenerationShip. In reality, there isn't actually a system of that kind that can be reached in that timeframe, so they had to make one up. [[note]]In fact, nothing like that exists within hundreds of light-years of the Solar System, not even assuming that terraforming dozens of planets takes precisely zero time and that EarthThatWas has to be abandoned pretty much, well, ''tomorrow''. There are 4-, 5-, and 6- star systems, [[http://en.wikipedia.org/wiki/Castor_%28star%29 the closest of which]] is 51 l.y. away, but they're all composed of sets of double or triple stars orbiting each other, not four around a common center.[[/note]]
* In ''Film/JupiterAscending'', Jupiter's parents are said to have met while stargazing at the shore of Neva in Saint-Petersburg. Saint-Petersburg is in fact overcast during most of the year, and even when the sky is not clouded, stars can't be seen there. In addition, in summer the sky over St. Pete never gets dark enough to see any stars - that's the famous "White Nights of St. Petersburg", a phenomenon also well known in other northern locales.
* In ''Literature/FoundationsEdge'', Trevize and Pelorat are discussing a legend about a particular pentagon of stars. Pelorat assumes it's a legend centuries old, but Trevize states it must be a recent one and, moreover, one originating from the particular system they are in, because there is only one inhabited system from which the stars form a perfect pentagon. Moreover, it is comprised of stars with high proper motion, and was noticeably distorted as late as a century ago.

[[folder:Mangled Celestial Motion -- Made-To-Order Eclipses]]
* ''Film/{{Apocalypto}}'' features a solar eclipse. The very next night, there's a full moon, which is odd considering that a ''solar'' eclipse can only happen at a new moon. (''Lunar'' eclipses, on the other hand, can only happen at the full moon.) The Moon is obviously like a great big lightbulb a writer can turn up or down, depending on the level of light needed at night. Since it's heavily implied that the Mayan priests secretly know how to predict eclipses, this leads to the amusing FridgeLogic that the characters know better astronomy than the writers.
* ''Series/BuffyTheVampireSlayer'': The Season 3 finale features a solar eclipse that goes from zero to total in about five seconds, then stays that way for the duration of the entire climactic battle. Apparently the mayor's magic is powerful enough to first speed up the earth's rotation, ''then stop it dead in its tracks for a while.''
* ''Film/{{Ladyhawke}}'': A full moon is followed a few days later by a solar eclipse, followed a few days later by a quarter moon. Though the novelization, by SF writer Joan Vinge, corrects this.
* Something alike happens in the Spanish TV series ''Series/AguilaRoja''. A few days before a full moon there's a solar eclipse.
* ''Series/{{Heroes}}'' has issues with eclipses. The pilot has a reasonably brief eclipse, but it's visible in both New York City and Tokyo at the same time. The eclipse that robs everyone of their powers in Season 3 is even worse; not only is it visible across the globe, it lasts for ''hours''. Why? Because is it says so, right here in the script, that's why.
* Justified in ''VideoGame/GoldenSunDarkDawn''; the TotalEclipseOfThePlot is artificially caused by a prehistoric {{Magitek}} doomsday device.

[[folder:Mangled Celestial Motion -- Constellations Are Constant]]
* ''Film/{{Stargate}}'': The way that constellations are used as a Cartesian coordinate system begins with the idea that a constellation is a fixed point in space. That probably makes it easier to build things you can just walk through to cross interstellar distances.
* Subverted in ''Series/StargateSG1''. The SGC cannot dial any address other than Abydos until Daniel Jackson discovers information that shows how to shift gate addresses to compensate for passing time.
* ''Film/SpaceMutiny'': Constellations are repeatedly referred to as meaningful divisions of space.
* ''Series/DoctorWho''
** The Doctor specifically mentions that his homeworld of Gallifrey was located in the Kasterborous constellation. How can one's own homeworld be in a constellation, when constellations are arbitrary shapes in the night sky as visible from your homeworld? We can't say that Earth is in a certain constellation because to us constellations are only visible from here. Additionally, stars that appear to be close together in a constellation may actually be hundreds of light-years apart; they might only look close together because of the scale involved.
** ''The Trial of a Time Lord'' repeatedly refers to Earth's entire constellation being moved by [[spoiler:the Time Lords]], ravaging Earth in the process and turning it into Ravelox. There have been a few attempts to address this in and out of fiction, but it usually comes down to viewers and writers just liking the sound of it. Maybe the Doctor does too.
** This error also crops up in ''Manga/TheFiveStarStories'', with many characters referring to the eponymous stars as a constellation despite living on planets orbiting them. They may just be talking poetically, though.
* ''VideoGame/StarControlII'': All the stars in a constellation are close to each other, forming contiguous regions on the hyperspace map. [[AllThereInTheManual The manual explains]] that these constellations are not the same constellations visible from any given planet, but were created after hyperspace was mapped from the patterns on the map.
* Shot down in ''Film/MenInBlack'', where the cryptic clue "The galaxy is on Orion's belt," is quickly dismissed as blathering nonsense.
* In ''Film/{{Prometheus}}'', the titular ship's destination is derived from an image of five stars which shows up in [[AncientAstronauts ancient sites around the world]]. The archaeologist hero says that a certain region of a very distant galaxy is the only possible match for this stellar configuration.
* In ''Series/ChildhoodsEnd'', the glyphs the Overlords use to communicate amongst themselves are in the shapes of constellations as seen from Earth's sky. If this system of writing had really been invented by the Overlords, they would most likely have used the shapes of constellations from their own homeworld's sky.
* In ''Series/{{Neverland}}'', a certain character points out that the constellation Orion is in a different position in the sky as opposed to Earth, due to Earth being situated in a different galaxy.

[[folder:Mangled Celestial Motion -- Spacey Schedule Errors]]
* In ''Series/SheWolfOfLondon'', Randi tells Ian not to worry about her transforming into her wolf form because "there won't be another full moon for months".
* In ''Series/TimeScout'', reading stars like a clock is portrayed as much more difficult and complex than it actually is.
* The ''Franchise/ScoobyDoo'' franchise opens on the night of a full moon, the only point in time the particular MonsterOfTheWeek is claimed to resurrect itself. The bulk of the episode, however, takes place on the next night, where another full moon allows it to do so again. A blue moon it ain't.
* A minor plot point in one Marcia Muller mystery involves two characters knowing that the next high tide will come 24 hours after the current high tide.
* Many writers donít understand that the phase of the moon is directly linked to the time of its rising and setting:
** A scene in Olivia Manningís ''Levant Trilogy'' has the main character watching a moonrise in the late afternoon. It is described as a new moon.
** In the 1892 novel ''Mona [=McLean=], Medical Student'' (which is essentially ExactlyWhatItSaysOnTheTin), a full moon is in the sky at the same time as the sun.
* As Creator/StephenKing admits, the moon cycle ''Literature/CycleOfTheWerewolf'' is designed to have a full moon fall on [[HorrorDoesntSettleForSimpleTuesday various holidays]] rather than an actual 30 day interval.

[[folder:Mangled Celestial Motion -- Planets Never Move]]
* [[WesternAnimation/LooneyTunes Marvin the Martian]] wants to [[EarthShatteringKaboom blow up the earth]] because it obstructs his view of Venus. Just wait a moment... In reality, astronomers would flock to such an event. There is plenty one can learn about both objects when a planet eclipses a star (or another planet).

[[folder:Mangled Astrophysics -- Timescales of Stellar Evolution]]
* In the novellization of ''Film/RevengeOfTheSith'', Anakin recalls a visit to a black dwarf star system: ''a frigid dwarf of hypercompacted trace metals, hovering a quantum fraction of a degree above absolute zero''. Even now there are no such objects yet, since they require hundreds of billions of years to cool, and the Universe isn't old enough; and Anakin lived "a long time ago", that's in a universe even younger than ours.

[[folder:Mangled Astrophysics -- Supernovae: Causes and Effects]]
* In ''A Swiftly Tilting Planet'', one of the sequels to ''Literature/AWrinkleInTime'', there's given yet another reason not to throw a nuclear war on Earth:
-->'''Gaudior:''' You know some of the possibilities if your planet is blown up.
-->'''Charles Wallace:''' It just might throw off the balance of things, so that the sun would burst into a supernova.
* In the 2009 ''Franchise/StarTrek'' reboot/alternate continuity film, the Romulan system is destroyed by the shockwave from a supernova...trouble is, the star shown exploding is an average-looking ''yellow'' Main Sequence star (like our own), which are neither hot enough nor massive enough to generate a supernova. Supernovae form almost exclusively from extremely massive blue-white stars.[[spoiler:Finally explained away on ''VideoGame/StarTrekOnline'' as the result of the local BigBad AncientConspiracy.]]
* The final result of Adam Warren's ''ComicBook/DirtyPair'' arc "Fatal But Not Serious" (during which [[CloningBlues a cloned Yuri]] raises hell on a planet) is the launch of a supernova-causing weapon to the nearest sun, which makes it explode with such power that ''other supernovae will occur from the shockwave''. This is not possible-supernovae don't produce a "shockwave" powerful enough to create "sympathetic explosions" of other suns (''especially'' because they are normally too far away from each other for this to happen, if it ''could'' happen in RealLife), and while it's never said about what the weapon can cause other than that it can cause supernovae, it's easy to assume that such a mess would be beyond the designer's original desire (and it was unmodified, mind). [[WalkingDisasterArea Just another thing that could be chalked to their inhumanly bad luck]], apparently.
* A similar chain reaction occurs towards the end of the Andromeda arc of ''Literature/PerryRhodan'' in the center region of that galaxy after a star is destroyed with a largely untested prototype weapon ''there''. This can potentially be handwaved -- [[NegativeSpaceWedgie hyperspace to the rescue]] -- in that the star in question was one of six blue giants making up one of the "main" [[TeleportersAndTransporters matter transmitter]] stations in a network capable of moving entire fleets on an intergalactic scale, and any side effects (including pretty effectively wrecking the network in question for good) thus probably weren't caused purely by its physical detonation.
* Larry Niven's ''Literature/{{Ringworld}}'' and ''Literature/KnownSpace'' mention a supernova chain reaction at the core of the galaxy happening thousands of years ago[[note]]To be fair, before the [[ScienceMarchesOn now commonly accepted and supported by observations]] view of black holes and/or star formation galore powering active galactic nuclei such as quasars, that was once proposed as one explanation to power them[[/note]].
* In ''Literature/LifeTheUniverseAndEverything'' the Ultimate Weapon of Hactar and the Krikketers is a cricket-ball sized bomb that can start a simultaneous supernova chain reaction to destroy galaxies and the entire universe. The reaction occurs in hyperspace, disregarding the duration of energy travelling through time and space, the distances between stars, the distances between galaxies, and the size of the universe.
* In ''Film/FantasticFour2005'', Johnny Storm's power is to make himself hotter while being immune to the effects of his own heat. Reed Richards speculates he could make himself hot enough to make the air molecules around him "go supernova"; it turns out Reed's theory is correct as Johnny makes himself hot enough to create a supernova to incapacitate Doctor Doom. The term supernova implies an immediately unstoppable explosion on an astronomical scale, of massively high temperatures. Johnny raises the temperature by creating a fiery tornado limited to a twenty foot wide area. The Invisible Woman waits a few seconds to begin containing this blaze by surrounding it with her force field, not encasing it in a sphere, but leaving the top and bottom ends open as the force field slowly goes up to follow the rising flames, and then contains it at the last second. The flames appear no hotter than an ordinary blaze, yet this blaze is supposed to represent the temperature of the air rising over a few seconds until reaching the superhot temperatures required to create this explosion. This extreme rise in temperature does not suddenly kill everyone around him due to radiant heat. The explosion goes off with a small pop, and is shown slightly expanding the force field as it appears to buckle, while a real supernova, going off within the atmosphere, on the surface of the planet, would have already obliterated the planet. The effect stops, leaving a charred ground within the area of the blaze, without showing any physical effect outside the confines of the force field, without creating deadly radiation, and without burrowing through the Earth's crust or igniting the rest of the atmosphere. The Earth is still fine, the ground is scorched at the surface, the metal suit Doctor Doom wears only appears hot, but is not hot enough to burn through his body, and underneath the suit his body is somewhat burnt but he still survives intact. Because a '''nuclear fusion reaction''' going off at close range is not that hot. It looks like this was never a real supernova in the first place, but a flamey explosion effect that happened to be called a supernova.
* ''VideoGame/FinalFantasyVII'': Sephiroth casts Supernova, destroying the planets of the solar system, and the sun, all so the effect of the supernova can travel to the planet and deal damage to the party, who are supposed to be in a crater, or maybe another dimension, a dimension where Supernova can be cast multiple times, and the planet remains just fine after the battle, so it would only make sense if it's not literally happening as depicted.
* In the episode ''A Planet Blown To Pieces'' of ''WesternAnimation/IlEtaitUneFois''... Space, the leaders of the [[TheFederation Omega Confederation]] discuss about the primary star of a multiple star system, where the antagonists (Cassiopeia) are building a military base, going supernova (it fall into the next category too, since they often refer to it as a ''nova'') soon. Not only supernovae do not work the way it's explained there but also in the show people are far more concerned about the debris of the explosion -that moves far slower than the light, thus not reaching the planet where's the base is located until days later and allowing Omega to assembly a fleet of ships to save the prisoners used as construction workers- than the energy emitted by it. In RealLife, the energy emitted by the supernova is '''''far''''' more dangerous than its debris, and it moves at the speed of light -so no days to rescue everyone on that planet, as happens there (at best, hours)-[[note]]The sheer dumbness of a general who decides to build a base in a place so dangerous, ignoring those who warn him about the instability of that star, ''and even with the supernova having destroyed the planet'' sends ships to savage base's equipment is not discussed here[[/note]].

[[folder:Mangled Astrophysics -- Nova]]
In more than one work of fiction, a star like the sun is said to end its life by "going nova." The implication is that a nova is merely a supernova on a smaller scale. Even Creator/LarryNiven brushed up dangerously close to this mistake in his short story "Inconstant Moon."\\
In reality, a nova is an outburst caused by a white dwarf sucking material off of a companion star; when enough material is accreted on the white dwarf's surface, it gets hot enough and dense enough to undergo nuclear fusion. This produces an outburst that reaches peak brightness in a few hours, then cools back down again over a few days or weeks. Some white dwarfs are known to be "recurrent novae", undergoing a nova outburst at more-or-less regular intervals of a few years or decades. (If the white dwarf accretes ''so'' much material that its mass exceeds 1.44 solar masses, it will explode spectacularly in an event called a Type Ia Supernova. Unlike the supernova that ends a massive star, this type of supernova produces no neutron star.)\\
When a sunlike star ends its main sequence lifetime, it doesn't "go nova", it swells into a ''red giant'' over the course of a few million years. In the process, the center is expected to undergo a "helium flash", similar to a type Ia supernova. The core stays together and the effects don't reach the outside of the star because of the rest of the star sitting on top.\\
Even fictionally "blowing up the sun" should never, ever result in a "nova." Supernova, maybe, but not nova.

[[folder:Telescopes 101]]
* In ''Film/LaraCroftTombRaider'', Lara Croft observed the alignment of Pluto and Neptune through a telescope in a room full of what looked like 20 floodlights. If these two had tried to be too dim to see in that situation, Lara would have just kicked their butts. They must have been really trying to be bright little planetary bodies that night out of sheer terror.
* The first AdBumper (indeed very first segment) of [[http://youtu.be/56AxK3LqTxY this collection of 1984 commercials and ad bumpers]] shows a ground-based observatory frantically turning to get a view of a UFO. Not only is the UFO in question too close to resolve clearly by the telescope, but observatories can't turn that fast.
* In the season 6 finale to Series/TheBigBangTheory, "The Bon Voyage Reaction", Raj shows his girlfriend the International Space Station, using a telescope to do so. The problem with this is the ISS orbits the earth every 90 minutes, so it is constantly moving. A non-computer-controlled telescope's field of vision is ''small'' so you would have to keep moving the telescope to see the ISS or it would whiz by very quickly. [[http://www.nasa.gov/vision/space/travelinginspace/f_skywatch.html The telescope was probably unnecessary anyway because the ISS is usually visible to the naked eye as it moves across the sky.]]
* Several works of fiction show amateur astronomers viewing meteor showers through a telescope. In fact, a telescope is the absolute ''worst'' thing to view a meteor shower through, since you need as much sky coverage as possible. The best piece of equipment to view a meteor shower? A lawn chair. Subverted (intentionally or not) in an episode of ''Series/MalcolmInTheMiddle'', in which a group of nerds attempt to view a meteor shower through a telescope, only to have their fun ruined by Malcom and his brothers throwing food at them. They eventually get their own back, and knock Malcom and his brothers onto their backs, where they then view the meteors.

[[folder: Bad Nomenclature ]]

* In the [[AnimeFirst manga version]] of ''Manga/YuGiOhGX'', the BigBad summons his most powerful monster--[[LightIsNotGood The Supremacy Sun]], strongest monster in the "Planet Series". [[AssPull Somewhat]] [[JustifiedTrope justified]] in that said BigBad grew up in AncientEgypt--''Anime/YuGiOh'''s AncientEgypt... [[spoiler: [[ScrewTheRulesIMakeThem and made the Planet Series, himself.]]]] This may be a translation issue. Japanese things actually call everything ''stars''--"wakusei" (惑星) literally translates to something like "confusing star" ("planet", by the way, comes from a word meaning "wanderer", probably for similar reasons).
* In ''TabletopGame/TheWorldOfDarkness'' supplement ''Infinite Macabre'', the term "galaxy" is explicitly stated to mean "systems of stars orbiting one another" or "systems of planets orbiting one or more stars." Also, they're separated by hundreds of thousands of parsecs at least, millions of parsecs at most. By way of reference, the nearest "galaxy," using the above definition, to our "galaxy, again using the above definition, is the Centauri system, roughly 1.5 parsecs away. Talk about scale problems...
* In the 1959 film of ''Film/JourneyToTheCenterOfTheEarth'', Professor Lindenbrook remarks that more is known about the stars and galaxies than about the depths of our own planet. The film is set in the mid-1800s, when the term "galaxy" only applied to our own Milky Way; the distant celestial objects now known to be other galaxies were then called "spiral nebulae".
* In the ''WesternAnimation/TheGrimAdventuresOfBillyAndMandy'' episode "Little Rock of Horrors", the Brain Eating Meteor" is referred to as a meteor even though it is technically a meteorite, having already impacted the Earth; Irwin even points this out in the video game. (Of course, it makes ''perfect'' sense to anyone who points that out that this meteorite being confused for a meteor talks, eats brains, ''sings'', etc...)

[[folder:Fake-Looking Celestial Bodies]]
* ''Franchise/StarWarsExpandedUniverse'':
** The planet Bespin is stated by canon to be a gas giant, but is milky-white and stripeless, and generally looks like Venus. A UsefulNotes/{{Venus}}-like planet is an even better place to put a CloudCity, but it's not a gas giant, even if canon states it to be such. However, [[http://en.wikipedia.org/wiki/Sudarsky_extrasolar_planet_classification not all gas giants look alike]]. A gas giant in the habitable zone would have white water clouds. An orange color could be caused by the presence of methane in the atmosphere (airborne methanogenic bacteria?). The planet could lack stripes if it had a slow rotation.
* This does NOT excuse the dull red color of the gas giant Yavin. It looks like a brown dwarf, not a gas giant. Brown dwarfs are basically gas giants that are so big, they almost began nuclear fusion. Given that many star systems are binary, having one with a main sequence star and a brown dwarf is not inconceivable. Also, brown dwarves actually are [[http://en.wikipedia.org/wiki/Brown_dwarf magenta colored]], while a sufficently hot gas giant (as in, close to it's parent star) might slightly glow red. Whether it could harbor a habitable moon is up to debate, but it could also be just a matter of the planet's chemistry.
** Or maybe Yavin is a young world that is still glowing hot from the residual heat of its formation. [[https://arxiv.org/abs/1101.0606 Saturn and especially Jupiter]] are stated to have been hot enough just after that event to shine like tiny suns.
* A very common SpecialEffectFailure in video games is the "bright sky, black moon" effect. Video game designers try to make a moon with variable phases and combine it with an unrealistically bright sky full of Hubble-style nebulae. The moon's dark side, quite realistically black, does not blend well into this sky and sticks like a sore thumb. This defect can be found in:
** ''VideoGame/KerbalSpaceProgram'';

[[folder:Nebulas Misrepresented]]
* The Crab Nebula and the Horsehead Nebula (because of their interesting appearance) were once depicted as being the home address of various aliens. If not, then they were in the neighborhood. These are not very hospitable areas to have a planet. The former is what remains of a star that went supernova in 1054 and the latter is actually an area where new stars are born. Also, as with constellations, these nebulae will not retain their appearance to a person travelling in space as opposed to on Earth. So an alien wouldn't think of himself as being from, say, the "Horsehead Nebula."[[note]]Though of course he might ''describe'' his home that way, when talking to earth humans.[[/note]]
** This fact plays a role in the Isaac Asimov novel "The Stars, like Dust", where the location of mankind's original solar system is forgotten. From the current power center, the Horsehead nebula looks nothing like a horse's head, so they speculate it's named after the original (mythical) explorer, one Horace Hedd.
** In ''Anime/BattleOfThPlanets'', the Spectrans are based in the Crab Nebula.
* There is a political cartoon where a father tells his son that every star has a system of planets. Not every star ''system'', every ''star''. [[SciFiWritersHaveNoSenseOfScale Where to even begin?]] Not every star has planets (very young blue stars don't, for example, since they don't have time to form), but it's a matter of ongoing scientific debate on exactly how common are planets.
* In more than one work of science fiction -- ''Film/StarTrekIITheWrathOfKhan'' comes to mind -- a ''nebula'' is treated like an opaque cloud where a space ship can easily hide from sight. In reality, nebulas are more rarefied than the best laboratory vacuum. The only reason a nebula is visible as a cloudlike structure is because it's ''light-years'' across, and astronomers have to peer through a ginormous expanse of this extremely tenuous material.

[[folder:Comet Impacts Don't Work That Way]]
* ''Film/TankGirl''. The opening narration says that a comet hit the Earth and somehow got rid of most of the liquid water on Earth (as shown by the dry sea beds), presumably by evaporating it. It also resulted in no rain falling for 11 years. Unless the comet was made of some crazy compounds designed to utterly destroy water molecules, the result of all that water evaporating should have been 1) the entire planet being flash-broiled, and 2) the mother of all greenhouse effects and downpours when all of that water vapor condensed and returned to the ground. (Unless the comet hit the Earth ''so'' hard that it sent all the water out into deep space; but any comet impact of that magnitude would also shatter the Earth's crust and turn it into a lava world.) The dialog of the Water And Power personnel implies that vast amounts of water are hidden under the desert, but it's even less likely that the comet impact could have caused that.

[[folder:Completely inaccurate terminology]]
* In ''Film/HighlanderTheSource'', the '''galaxy''' suffers a major case of WhenThePlanetsAlign. One character offhandedly dismisses the phenomenon, suggesting "that could just be orbital wobble." To be fair, the film immediately says "No it isn't [[http://en.wikipedia.org/wiki/Barycentric_coordinates_%28astronomy%29 'orbital wobble']], this is clearly magic related to the Immortals."
* Like [[Film/{{Meteor}} the movie]] that it was licensed from, Creator/SternElectronics' ''Pinball/{{Meteor}}'' {{Pinball}} is named after a five-mile wide ''asteroid'' that's headed for the Earth.
* Despite the fact that extrasolar planetary systems have been known for decades, and that astronomers already have an established convention for naming extrasolar planets by letter in order of discovery, interstellar-based science fiction still clings to the ancient trope of naming planets by number in order of distance from their star. This can be largely pinned on RuleOfCool, since "Altair 4" and "Rigel 7" sound infinitely cooler than "Altair e" and "Rigel h".
* The word ''astronomy'' is itself often confused with ''astrology''. Many real-life astronomers get asked about [[WesternZodiac star signs]].

[[folder:Destroying Killer Space Objects in Earth Orbit Is Perfectly Safe]]
* ''ComicBook/InfiniteCrisis'': Planets are created and destroyed, not that far from the Earth's orbit, without disrupting the orbit of the Earth, and the orbit of other bodies in the solar system, and without causing global flooding on the Earth or causing any debris to hit the Earth.
* Subverted in Webcomic/OnePunchMan, as Saitama manages to destroy the meteor threatening to destroy the city... but doesn't destroy any of the meteorites coming from the broken pieces, completely decimating several cities.
* In VideoGame/BillNyeTheScienceGuyStopTheRock, the Meteoroid And Asteroid eXploder, MAAX, is designed to deflect or otherwise destroy asteroids or meteoroids which are large enough to pose a threat to the survival of life on Earth as people know it. The latter part would actually do ''more damage'' in real life since destroying asteroids and meteoroids large enough to destroy or decimate Earth would only create ''even more'' asteroids or meteoroids to impact the Earth - albeit smaller ones.
* ''Film/IndependenceDay'': A ship, said to be a quarter of the size of the Earth's moon, is destroyed not too far from the Earth's atmosphere, without sending debris crashing into the planet or disrupting the tides.

[[folder:Light pollution does not exist]]
* The ''Saving Hope'' episode "Vamanos" has a scene with Charlie and a patient watching a meteor shower from the hospital roof. The meteors are easy to see despite the fact that these people are in downtown Toronto surrounded by brightly-lit buildings. It would be either difficult or impossible to get this kind of view in a light-polluted area. Usually the only celestial objects visible would be particularly large and bright ones such as Jupiter.

[[folder:Orbital mechanics do not work that way]]
* In ''Film/{{Gravity}}'', the FlechetteStorm resulting from [[spoiler:the destruction of the shuttle and the Hubble being hit by satellite remains]] is told to be moving so fast that it would orbit the Earth and come back to hit the main characters in 90 minutes. The problem? If the debris was indeed moving that much faster than the astronauts at the same elevation, it would break orbit and shoot off into space or, at least, move in a different orbit and, thus, be harmless to them. That's not even bringing up the fact that they have somehow caught up to the ISS which is moving in a completely different orbit from the Hubble (which is where they are) without much effort.

[[folder:Stars with pointed spikes]]
* The stars with pointed spikes -usually four, resembling a plus sign; however there're variants of this such as a x-shaped star-, so prominent and known after so many space images are actually caused by the vanes that support the secondary mirror of reflecting telescopes, often known along with the holder of that mirror as ''spider''[[note]] most professional telescopes as well as amateur ones above a certain size, and of the largest ones currently in service ''all'' of them -including the Hubble Space Telescope-, because is ''far'' cheaper and easier to build a big mirror than a big lens, are [[http://en.wikipedia.org/wiki/Reflecting_telescope reflecting telescopes]] that use a set of mirrors to work [[/note]] and do not exist in reality, nor when one sees a bright star without optical aid and/or in the space would see it with those spikes [[note]]Watching a bright star with a telescope, at least one of the classical type with lenses (refracting telescope). produces due to the properties of the light a bright disk (that is '''''not''''' the actual disk of the star) surrounded with rings instead of a point-like source; through a reflecting one, however, often one can see the spiky star effect[[/note]]. The effect is known as [[http://en.wikipedia.org/wiki/Diffraction_spike Diffraction spike]] and there're photographic/camera filters to simulate it.
** Same for the haloes visible around them, that are optical effects, except in some cases where they are actual nebulosities surrounding the photographed star(s).
** A related effect are vertical images that often appear images of bright stars taken with telescopes that mount [=CCDs=] -the electronic devices found at the heart of digital cameras- instead of traditional photographic plates, that are produced when the individual bins of a [=CCD=] overflown and spill in vertical as is easier to happen due to the [=CCD=]'s structure, an effect known as [[http://en.wikipedia.org/wiki/Charge-coupled_device#Blooming Blooming]]

* In the Creator/HansVonHozel story ''Werewolves'', executives on earth successfully ''harpoon the sun''.
* The ''WesternAnimation/SpaceGhost'' episode "The Heat Thing" shows Jupiter as having a solid surface with a normal atmosphere instead being a gas giant.
** An episode of ''WesternAnimation/TheImpossibles'' featured the same. Creator/HannaBarbera didn't seem too worried about accuracy in the 60s.
** Same for the arcade game ''{{VideoGame/Solar Warrior}}''. Jupiter appears as a desert world complete with ''Literature/{{Dune}}''-like worms, likely as a ShoutOut to it.
* In ''Series/{{Space1999}}'', exterior shots of Moonbase Alpha always show a sunlit landscape, illuminated at about the same angle every time. This is in blatant violation of the basic premise of the show: the moon has left the solar system and is hurtling through interstellar space, usually light years from the nearest star.
* The miniature sun in ''Film/SpiderMan2'' shows no effects of radiant heat, radiation, or gravity on those nearby, having no effect on physical matter when handled by a set of metal arms or when idly floating in an unshielded "containment field". There's no way to estimate mass or density. Is the sun's own gravity holding it together, and is that gravity coming from its mass despite its size, as its miniatured molecules simulate macro-scale gravity while still allowing thermonuclear fusion of hydrogen into helium at its core to take place, in a safe and cozy environment, without killing everyone nearby?
* In ''WesternAnimation/TheSpongeBobMovieSpongeOutOfWater'', when Jupiter and Saturn crash into each other, they appear to be made of solid rock. Jupiter and Saturn are gas giants. However, like many other parts of the film, this can likely be excused by RuleOfFunny. [[spoiler: It happened when the [[ItMakesSenseInContext when the watcher of the universe was in the restroom]].]]
* In ''Film/{{Pixels}}'', the space probe with message to aliens is said to have reached alien life and given aliens enough time to prepare and reach ''us'' in slightly more than thirty years. Unless it has OrionDrive (forbidden by US conventions), it should be somewhere around Pluto by the year the movie takes place in. Then again, the aliens may have been passing by the Solar System and just happened to rendezvous with it. Who knows?
* In the episode ''Happy Starday'' of ''ComicBook/BillyTheCat'' TV series, astronomers seem to look for an individual star, visible with nacked eye, and than name it, so it has not been seen. (How do they know, for what they look?) Besides, Mr. Hubert has to move to be in the light of his star, that he already sees. (If he sees it, its light falls on his eyes.)
* In ''VideoGame/DarkFall The Journal'', the amateur astronomer's room contains documents that describe a "new" constellation which he discovered by pure chance with an ordinary telescope. Not a new star, mind, but a whole group of them that no one had evidently spotted before.
* In the ''Series/StarTrekTheNextGeneration'' episode ''Galaxy's Child'', [[TheEngineer Geordi LaForge]] mentions ''everything'' in the Universe vibrates in a 21 cm radiation band. [[https://en.wikipedia.org/wiki/Hydrogen_line The change in quantum spin of the electron in single hydrogen atoms]] is the main source of these radio emissions, and ''not'' everything in the Universe does that[[note]]The cosmic microwave background, to begin with[[/note]].
* Many older works of fiction, such as ''Literature/TheTimeMachine'' and ''Literature/TheMagiciansNephew'', describe red giant stars as cold, even if their worlds are similarly distant as Earth from the Sun. It is true that red giants are cooler than younger stars, but "cooler" is relative, and they are also '''much, much''' closer to their planets, and any such planets would be roasted rather than chilled.
* In the ''TabletopGame/ForgottenRealms'' Player's Handbook for ''TabletopGame/DungeonsAndDragons 3.5'' is stated that Selûne, the Abeir-Toril's moon, orbits at just 20,000 miles of the planet (for comparison purposes, this is less than 1/12th of the mean distance between the Moon and the Earth)[[note]]Retconning likely by error the previous version, where it was stated to be [[http://www.spelljammer.org/worlds/Realmspace/Toril.html 183,000 miles]] away[[/note]]. The effects of having a large satellite (it's stated to be similar in size to the Moon) so close such as ''very'' powerful tides and tidal-caused earthquakes are not addressed at all[[note]]Nor the spectacularity of a full moon night with one so large. Nor the possibility of the moon crossing the Roche limit and being ground into gravel.[[/note]].
* Also in the D&D splatbook, Elder Evils, the World Born Dead, Atropus, consists of a small rogue moonlet that seeks out planets covered in life and destroys them via bodyslam. The book describes Atropus as having a tiny (planetary-wise) diameter of 700 miles. However, base on the mechanics centered on it, the surface gravity is around 2/3rds of that of Earth's. This means that either magic is making things weird (it is a god's corpse after all) or Atropus is entirely made up of something far denser then lead, giving it a mass more comparable to Mars.
* Since Uranus is not visible from earth using the [[HehHehYouSaidX naked]] eye, anyone who invokes UranusIsShowing is pretty obviously talking about someone's bunghole rather than the planet.

->'''Reggie:''' Orbital wobble is one thing, but this...this is outside the laws of celestial mechanics!