[[quoteright:250:[[Series/StarTrekDeepSpaceNine http://static.tvtropes.org/pmwiki/pub/images/minefield_796.jpg]]]][[SpaceIsAnOcean Space is, of course, an ocean]]. And sometimes your SpaceNavy needs to block access to a [[SpaceStation port]], a space lane, or even an entire planet. How to do this? Why, SpaceMines, of course. These are like their [[SeaMine seagoing counterparts]], but ''IN SPAAAAACE!!!''

Just like there are several types of [[SeaMine Sea Mines]], so there are also many types of SpaceMines. Most common are proximity mines, that go off when a ship gets too near, and contact mines that go off when they hit a ship's hull. Magnetic mines are attracted to metal hulls. Homing mines are essentially missiles that sit around until they detect a ship's engine or weapon energy signature, then angle themselves at the target and let fly. Some mines are miniature weapons platforms that open fire when ships get too close. Remote-detonated mines can be set off by a waiting vessel when a target ship gets in range. Nuclear mines have nuclear warheads in them. Then there are mines that rob ships of power (dampening fields) instead of just exploding. There are many other variations and combinations.

In real life, there would be some [[FridgeLogic major limitations]] to this trope. However, since SpaceMines seem to be an ubiquitous part of [[SpaceOpera Space Operas]], sometimes the savvy writer thinks of the above limitations and writes around them - and real-life applications have even been discussed in military circles.

* In order to secure a whole planet, you'd have to mine space three-dimensionally in order to be effective. In fiction this is [[TwoDSpace often not done]].
* Earth's ocean and sea terrain contains a lot of inlets, natural harbors, bays, straights and other types of terrain that make natural choke-points where the use of mines is a practical way to deny or substantially delay passage to unwanted ships. No such barriers or terrain exists in space to prevent ships from circumnavigating such a barrier. Even protecting a very small moon with a density of one mine every few thousand cubic km would require huge numbers of mines and logistical support to successfully achieve coverage. The same logistical resources would be of better use in improving detection and interception/quick reaction capability. Can be justified if there IS a conveniently narrow pathway to barricade, such as a local entrance to {{Hyperspace}} or the PortalNetwork, or if the object to be surrounded by mines is fairly small, such as an asteroid base.
* Laying mines takes time, and the larger area you need to cover, the number of mines you would need increase quadratically. To cover large or even moderate areas could take hundreds of years, even if it only took a few seconds to lay each mine. Justified if the mines have potential to locate and approach, or shoot, their targets from massive range, thus ensuring blockade functionality despite low minefield density, or can be all released in a single spot and relocate and organise autonomously. As for the matter of quantity, this can be explained by having automated manufacturing and minelaying facilities operating over lengthy time periods, or have the mines themselves be self-propagating Von Neumann machines.
* Sea mines are deployed under water, greatly complicating the task of detecting and clearing them. There is no such barrier to visibility for SpaceMines. Unless there were some sort of mitigating factor (sensory disruption, cloaked mines, etc.) space ships could just pick them off with long range guns/lasers/missiles/decoys/whatever. May be partially justified by the fact that, unlike enemy ships, they can be inert, dormant and undistinguishable from generic space debris until they're close enough to strike.
* Everything with mass has gravity. In space, little things that are relatively close to each other tend to clump up -- this is how planets and stars are born, and why there are no {{Asteroid Thicket}}s. The mines would need some way to fight or negate the effects of gravity on each other that also wouldn't run out of fuel.

[[IThoughtItMeant Not to be confused with]] [[AsteroidMiners Space Mining operations]], mining valuable materials from [[AsteroidThicket asteroids]] or other planets InSpace.

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!!!Examples :

[[foldercontrol]]

[[folder: Anime And Manga ]]

* There are massive space minefields around the Men's Planet (Tarak) that is visited towards the end of ''Anime/{{Vandread}}'' (second season). They are used to reveal [[spoiler:First Mate BC]] as TheMole, since s/he knows the friend-foe codes of the mines that allow ''Nirvana'' to pass them.
* Mines are used in multiple battles in ''Anime/LegendOfGalacticHeroes''.
* In ''Anime/MobileSuitGundamWing'', the area around the space colonies is seeded with mines to prevent any unauthorized travel. Trowa's first assignment upon enlisting with OZ is to help destroy the mines, as part of OZ's "kinder and gentler" facade.
** The original series had both the Gyan, which could deploy floating mines from its shield and the MSV model kit Zaku Minelayer, which was just the standard {{Mook}} with a bigger backpack that dropped mines.
* ''LightNovel/CrestOfTheStars'' has mines being one of the three main weapons being used in space battles (the other two being [[FrickinLaserBeams anti-proton beams]] and [[MagneticWeapons railguns]]). Ships deploy mines around themselves as defense, as the mines are self-piloting and follow the ship's movements; or employ them as self-guided missiles against distant enemies. The nature of space combat in the series makes them the most effective long-range weapons, with the particle beams and railguns being short-range options for when you can actually see your enemy.

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[[folder: Fan Works ]]

* In ''Fanfic/TheWrongReflection'' the Terran Empire lays a minefield in the path of an oncoming Klingon/Cardassian attack fleet. The USS ''Bajor'''s Master Chief Wiggin spots the minefield and they're able to drop out of warp in time to avoid it, but much of the fleet runs right into it and the Klingon general is killed.

[[/folder]]

[[folder: Film ]]

* The Tothian minefield in ''Film/GalaxyQuest'' provides a rather dangerous shelter for the ''Protector'' when "Taggart" and his crew find themselves outgunned by Sarris. It [[ChekhovsGun comes into play again]] in the finale, when they use it to pull a variant on the WronskiFeint against Sarris' ship: [[spoiler: the magnetic mines trail behind the ship, and Sarris runs straight into them]]. Averts the usual problem with space mines in that the field has enough layers to cover a significant portion of space (enough to look like a nebula from a distance which is why they fly into it in the first place), though still woefully small in the grand scale of things.

[[/folder]]

[[folder: Literature ]]

* Stewart Cowley's ''Spacecraft: 2000 to 2100 A.D.''. During the war with Proxima Centauri, the perimeter of Earth's solar system was seeded with nuclear mines. They would home in on the warp generators of arriving enemy ships and destroy them while they were recharging their power banks after the warp jump.
* ''Literature/HonorHarrington'' has this; it gets around SpaceIsBig by having the mines basically be the same 10,000-kilometer-range laser warheads found on their missiles. They later come up with a system defense variant of their missile pods, creating [[RecursiveAmmo missile-firing mines]] with much greater range. Additionally, mines tend to be placed to cover small areas: the orbits around a planet, a wormhole exit, or (occasionally) quickly laid in the path of an incoming fleet. The visibility issue is avoided in that professional forces (ie. everyone who isn't StateSec) use them as a force multiplier rather than a sole defense: slow down to take potshots at the minefield and you leave yourself wide open for attacks from the system-defense forces.
* ''Literature/HaloFirstStrike'' has Moray Space Mines, which can be homing or stationary.
** ''Halo: Ghosts of Onyx'' has nuclear HORNET mines.
* In ''TourOfTheMerrimack: The Myriad'', there are mines surrounding the entrance of the wormhole to Origin.
* In the StarTrekNovelVerse, the Gorn Hegemony makes use of these, and fields specialized mine-launcher ships. One such vessel causes trouble for the StarfleetCorpsOfEngineers in the story “Where Time Stands Still”.
** The Cheka, a race appearing in the StarTrekDeepSpaceNineRelaunch, employ space mines during a battle in the novel ''This Gray Spirit''.
* A number of space mines appear in the StarWarsExpandedUniverse, where they are particularly useful when placed along the exit points of hyperspace routes. Besides the usual exploding types, [[ComicBook/XWingSeries Wraith Squadron]] encountered a variant that used a gravity well generator to snatch fighters from hyperspace before triggering an ion pulse to disable them.
* Creator/EEDocSmith's ''Family D'Alembert'' series - in the seventh book, the heroes have obtained (or so they think) the location where the enemy fleet is going to assemble. The best place in which to deploy for the killing ambush follows as a corollary. It's also seeded with mines. [[spoiler:The Fleet avoids annihilation through a stroke of luck.]]
* Pops up in a chapter of ''Literature/BattlefieldEarth'' as a way for the rag-tag human freedom fighters to defend against other invading aliens following the initial liberation of Earth. ''Where'' the humans got them, how they managed to whip up a few thousand space mines, or why the Psychlos had the mines sitting in storage somewhere instead of in use, is never explained.
* The hypernet gates used for transit between star systems important enough to justify the expense in Literature/TheLostFleet turn out to also be capable of supernova scale detonation. In a sequel series the character discover two other species that also have the gates, are aware of this alternate use, and use it accordingly (read: ''not'' in important systems, but as perimeter system defensive mines).

[[/folder]]

[[folder: Live Action TV ]]

* In the pilot of the original ''Series/{{Battlestar Galactica|1978}}'', the Galactica must pass through a narrow region of space in a [[SpaceClouds dense nebula]] that has been mined by the Cylons.
* In the ''Series/BabylonFive'' episode "Matters of Honor", we see a Centauri minefield deployed to interdict access to a planet. This minefield actually consists of orbiting weapon platforms that fire on intruding starships instead of merely exploding when they get within range.
** Captain Sheridan also used nuclear warheads as mines on at least two occasions, but these were remotely detonated from a starship when enemy vessels were deemed close enough.
* ''Franchise/StarTrek''
** ''Series/StarTrekTheOriginalSeries'' episode "Balance of Terror". The Romulan ship uses one of its [[SelfDestructMechanism self destruct devices]] as an impromptu mine in an attempt to destroy the Enterprise.
** ''Film/StarTrekIITheWrathOfKhan''. In the UnwinnableTrainingSimulation that starts off the movie, the ship the ''Enterprise'' needs to rescue was disabled by a gravitic mine.
** ''Series/StarTrekTheNextGeneration''
*** "Booby Trap". The Enterprise enters an asteroid belt that contain "acceton assimilators", mines which drain the ship's power, convert it to deadly radiation and beam it at the ship.
*** "Chain of Command Part II". An Enterprise shuttlecraft is used to lay mines in the [=McAllister=] C-5 Nebula, trapping the Cardassian ships hiding inside it. In this case, the ships were already present, so the mines just had to be placed near/on them.
** ''Series/StarTrekDeepSpaceNine''
*** During the Dominion Wars the ''Defiant'' mined the entrance to the Bajoran wormhole. At least in this case, the mines were protecting a single, uni-directional portal and were both cloaked and self-replicating to prevent easy removal.
*** The Klingons established an illegal cloaked minefield in "Sons of Mogh." The mines are dormant and have to be remotely activated in event of war -- and would effectively cut [=DS9=] and Bajor off from support from elsewhere in the Alpha Quadrant.
** In ''Series/StarTrekEnterprise'', the Enterprise runs into a Romulan minefield surrounding a planet. The mines are cloaked and scattered everywhere, a rare example of such a field done right.
* The ''Series/StargateSG1'' episode "The Serpent's Venom" takes place in a space minefield where the mines all lock onto any sign of weapons, which is used by the Go'a'uld as a neutral meeting place. SG-1 has to reprogram a mine to attack one of the Go'a'uld ships at the meeting, in order to instigate a conflict. [[spoiler:Unfortunately, their plan [[GoneHorriblyWrong backfires badly]], instead of leaving the system, Apophis destroys his nephew Heru'ur's ship and use a fleet of cloaked Ha'taks he brought to protect his flagship from the mines. He ends up absorbing Heru'ur's remaining forces into his own empire]].

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[[folder: Tabletop Games ]]

* ''StarFleetBattles''. Ships can "roll a mine out a hatch" and leave it to blow up a ship pursuing them. Mines can be set to accept only certain sizes of ships as targets. Major space installations often had minefield belts protecting them. Some of the mine types available:
** The Romulans have a Nuclear Space Mine based on the ''Series/StarTrekTheOriginalSeries'' episode "Balance of Terror".
** Command mines can be ordered to detonate or to activate/deactivate themselves.
** Chained mines detonate when other mines explode.
** Transporter bombs can be beamed into position.
** Captor mines can fire weapons at targets.
* Iron Crown Enterprises' ''Cyberspace'' game had Orbital Mines for use against enemy spacecraft in orbit. Some had onboard computers and could make their own piloting/targeting decisions, others had to be operated by remote control.
* [=AKVs=] in TranshumanSpace are not exactly mines, but similar enough: they are AI-controlled missiles that can float in ambush until a [[InsistentTerminology craft]] flies near and then attack.
* ''TabletopGame/BattlefleetGothic'' has a large number of scenarios in which the defender can buy and deploy defence systems ranging from purely in-system patrol vessels and armed space stations through to this trope, with Orbital Mines (homing, slow moving, relatively myopic target acquisition) and Deadfall Torpedo Salvoes (ship-killing torpedoes, faster moving than mines, with slightly better target acquisition, but functionally non-homing once their drives come up). It's also possible to refit a [[TheBattlestar carrier]] into a mine-laying role, swapping attack craft squadrons for the capacity to drop a pair of mines.

[[/folder]]

[[folder: Video Games ]]

* ''VideoGame/WingCommander'' has Porcupine Space Mines (proximity, limited homing); there were also turret mines (miniature laser platforms), high explosive contact mines and viral mines (broadcast virus-infested transmissions to infect and shut down ship computer systems).
** Wing Commander III, in particular, justifies use of mines when one mission sees you mining jump points to keep the Kilrathi from surprising the Confed forces in system.
* ''VideoGame/TheBabylonProject'': In three levels of the Earth-Brakiri War, you have to navigate through a Centauri minefield. Unlike traditional contact or proximity mines, these mines ''shoot'' at you (see the ''Babylon 5'' example above).
* There's an online Flash game called ''Space Minefield''.
** Also one called ''Space Mines''.
** And a company called Cogmed created a flash game called ''Space Mine Patrol'' to demonstrate working memory.
* [[http://starwars.wikia.com/wiki/Space_mine Space mines]] appear often in the ''Franchise/StarWars'' [[Franchise/StarWarsExpandedUniverse Expanded Universe]], both in novels and in the games.
** Both the ''VideoGame/XWing'' and ''VideoGame/TIEFighter'' games feature mines that shoot at you, rather than exploding. Most of the missions that feature these tend to be quite [[NintendoHard difficult]].
** ''StarWarsRebelAssault II'' and ''RogueSquadron II'' also have space minefield levels.
* The first few seconds of Sector X in ''VideoGame/StarFox64'' has a cloud of mines you have to go through.
* ''VideoGame/{{Homeworld}}'' has Minelaying Corvettes. The mines themselves are proximity-triggered homing mines, solving the problem of mining in 3D space.
* ''{{Freelancer}}'' has a few minefields, which have their own haunting ambience theme whenever the player is near or within one. These minefields are less like a field of mines and more like a thick, spherical meshwork of explosives, which kill any intruding spacecraft[[note]] that aren't using cheats[[/note]] ''very'' quickly.
** Also comes with its own hilarious form of ArtificialStupidity: patrol routes for the [[SpaceStation space prison BPA Newgate]] graze the minefield surrounding it. Every so often one of the patrolling Bretonia Police Authority ships will plow into the minefield, [[DeathCryEcho screaming]] while everyone else does [[UnusuallyUninterestingSight absolutely nothing about it]].
* ''VideoGame/{{Elite}} 2: Frontier'' and ''Elite 3: Frontier First Encounters'' let you deploy these mines... or be blown to bits with them. Honestly, these mines are uneffective.
* Mines actually appear as obstacles in the games ''VideoGame/SuperMarioGalaxy'' and ''VideoGame/SuperMarioGalaxy2'', particularly in the [[OverlordJr Bowser Jr.]] levels.
* ''VideoGame/SwordOfTheStars'' has Minelayer sections in both destroyer and cruiser sizes. There are various warheads but all are proximity-triggered homers. There's also a Leap version that trades some power for much faster movement as an anti-{{Point Defense|less}} measure, as well as a Gravity mine that doesn't hurt but pulls ships to itself and an Implosion version that combines said Gravity effect with an actual blast. They can be very effective, especially [[AIBreaker against the AI]]. There's even an upgrade to the Complex Ordnance Launcher that allows you to launch a minefield from afar.
* The Artemis System Net from ''VideoGame/MasterOfOrion 2: Battle At Antares'' is a massive minefield that surrounds the system it's built at. It has a chance of damaging or destroying enemy warships that attack the system depending on the size class (i.e. the larger the ship, the higher is the chance of it hitting a mine with Doomstars having a nearly 100% chance).
* This is the special weapon (proximity, limited homing) of the Defiant-class in ''VideoGame/StarTrekArmada''.
** And becomes a relatively common aft weapon in ''VideoGame/StarTrekOnline'', with a variety of different payloads (including tractor beams). However, because mine spreads are stationary relative to the local map, and have such a limited homing range, their best use is possibly taking down other mines and incoming heavy torpedoes
* Also possible in ''SinsOfASolarEmpire'', mixing two of the above excuses with 2D Space, and direct lines of approach to separate gravity wells.
* Several varieties of Space Mines in ''[[VideoGame/{{X}} X3 Terran Conflict]]''. [=SQUASH=] Mines are your standard high explosive mines, Ion Mines target ship shields, Tracker Mines... [[ExactlyWhatItSaysOnTheTin track the enemy]], and Matter/Antimatter Mines are like [=SQUASH=] mines but with more boom. In theory. In practice only the names are different. They all do the same type and amount of damage. One of the most effective uses of the mines is to load your ship with them, get a ton of enemies to chase you, drop all the mines, then order one mine to self-destruct. Big bada boom.
* Stage 1 of ''VideoGame/RType Leo'' has space mines that form a laser grid with other mines.
* [[ProudWarriorRaceGuy Aera]] in ''VideoGame/VegaStrike'' has Porcupine "mines". It's a sluggish (about 0.5 g in any direction) AttackDrone with an [[LeadTheTarget autotracking]] gun and 100 shield-piercing shells to pelt enemies in range. It explodes if approached, but weaker than any missiles proper. In terms of volume and compatible mounts it's a "medium missile", which allows Aera escort fighters to carry a dozen of these pests, in addition to six mounts of the same weapon with much more ammo, rocket pods (in assault variant) and normal missiles.
* ''Stars!'' minefields attack enemy ships traveling above certain [[{{FTL}} warp speed]] and thus prevent a sudden invasion -- an important part of the game. Ships equipped with {{Ramscoop}} engines suffer more damage; those that aren't tend to rely on fragile fuel transports, and since mines, like missiles, aren't fully negated by DeflectorShields, unarmored ships are killed easily. Specialization in mines is a ''{{p|lanetOfHats}}rimary'' racial trait, "[[http://wiki.starsautohost.org/wiki/Space_Demolition Space Demolition]]". These guys have all 3 mine types, minelayer hulls, lay mines on the run and are much more capable both of surviving mine attacks and using their own mines offensively. They also use minefields as detection arrays -- if used correctly, this makes sneaking up on them almost impossible: move fast and get blown up, or move slowly and be detected early. Or run into normal and heavy mines, have surviving ships stopped by speed traps and detected -- unable to repair without blown up transports or even run away due to still being stuck in the middle of 3 overlapping fields. Conversely, [[ProudWarriorRaceGuy War Mongers]] don't have such defensive weapons at all.
* In ''AnotherCenturysEpisode'' (the original), one mission (loosely based on ''Anime/MobileSuitGundamWing'', mentioned above) has you clearing out a minefield so Relena Peacecraft can make a goodwill visit to the colonies.
* In ''VGA Planets'' ships with torpedo tubes can lay mines. Efficiency depends on TechLevel. It can be expensive in terms of restocking ammo, though mines that aren't swept can be scooped by another ship or even another allied player's ship, so it sometimes allows to reload empty torpedo tubes in the middle of nothing. Both laying and sweeping minefields are fleet orders, i.e. ships have to stand there and not do anything else other than defending themselves. [[SiliconBasedLife Crystals]] race also have web mines -- these stop enemy ships at random, so the fleets break apart and steadily drain fuel, so the victime can get stuck for good.
* Mines are used to defend a [[PortalNetwork Void gate]] in ''VideoGame/InfiniteSpace'', but the invading fleet cuts right through them with a massive missile barrage. The Oort Interception System around the prison planet Skantzoura is made up of mines that shoot anything that comes close like the ''Babylon 5'' example.
* In ''VideoGame/TenMinuteSpaceStrategy'', orbital minefields are one of the special traits your empire can develop which speeds up the destruction of invading enemy fighters on your planets.
* ''VideoGame/SpacePiratesAndZombies'' also the player to drop mines as a weapon. What you're really dropping is a cloaked dispenser that will scatter a limited area with cloaked mines that are attracted to your hull. One type of side-mission involves entering minefields to recover cargo though.
* ''VideoGame/DeadSpace3'' has a mined debris field about a planet. Said mines also seem to have some sort of guidance system, drifting towards active ships and people, but not derelicts and space junk. They also appear to have been dropped haphazardly throughout a debris field, which may indicate that they weren't intentionally placed, [[FridgeBrilliance but rather exposed and somehow activated when the ships holding them were damaged and vented to space.]]

[[/folder]]

[[folder: Web Comics ]]

* In ''{{Inhuman}}'', the whole planet Hekshano is cordoned with a minefield. Some pilots have races in there.
* In ''Webcomic/CommanderKitty'', [[SpaceStation Zenith Central]] [[http://www.commanderkitty.com/2011/05/01/out-of-the-frying-pan/ unleashes these on our heroes]]. Oddly enough, [[http://www.commanderkitty.com/2012/02/23/the-cat-with-the-plan/ despite being refereed to as mines]], they actually seem closer to AttackDrones as they fire lasers instead of explode. [[http://www.commanderkitty.com/2011/06/20/a-way-with-the-ladies/ Fortunately for our heroes]], they're also [[ArtificialStupidity dumb as bricks]] and [[AIBreaker can be fooled by flying backwards]].

[[/folder]]

[[folder: Real Life ]]

* While most science fiction applications of SpaceMines are ridiculous in practical application (see the [[Fridge/SpaceMines fridge logic page]]), it might be feasible to set up SpaceMines in certain high-traffic orbitals, e.g. geosynchronous orbit. Other targets would be those used in an orbital insertion after launch from a major ground-based spaceport. You could also position them at Lagrange points due to their use in the Interplanetary Transport Network.
** Space mines have actually been considered in real life studies as possible space weapons utilizing current tech. Examples:
*** http://books.google.com/books?id=AQROL_5mY5cC&lpg=PA53&ots=vn8i70rVAg&pg=PA53#v=onepage (1984)
*** http://www.fas.org/rlg/030522-space.pdf (2003)
*** http://www.unidir.org/pdf/articles/pdf-art2377.pdf (2004)
*** http://wuxinghongqi.blogspot.com/2010/08/chinas-space-weapons-exposured-russia.html (2010)
* Currently, space debris, also known as orbital debris, space junk, and space waste, is the collection of objects in orbit around Earth that were created by humans but no longer serve any useful purpose. These objects consist of everything from spent rocket stages and defunct satellites to erosion, explosion and collision fragments. To date there have been several known and suspected impact events, and several satellites have been destroyed.
** As the chance of collision is a function of the number of objects in space, there is a critical density where the creation of new debris occurs faster than the various natural forces remove these objects from orbit. Beyond this point a runaway chain reaction can occur that reduces all objects in orbit to debris in a period of years or months. This possibility is known as the "Kessler syndrome", and there is debate as to whether or not this critical density has already been reached in certain orbital bands.

So yeah, some degree of TruthInTelevision.

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