Space Is an Ocean

Sail onward, 'till you can't see the event horizon.

"When ships to sail the void between the stars have been invented there will also be men who come forward to sail those ships."

— Johannes Kepler

Maybe it's the vast expanses, the parallels with navigation, the romantic aspects, maybe it's the sense of adventure and danger, maybe it's the obvious parallels to the Age of Exploration, but for some reason, when people write about space, they tend to make parallels to the sea, as President Kennedy (himself a former naval officer) did in his "Space is the new ocean" speech. Often, it goes far beyond metaphor. Science Fiction writers frequently use nautical analogies for pretty much everything in space, and fill in the gaps in their own knowledge about spaceflight with details specific to sea travel.

For example...

• Spacecraft are often called "spaceships", and sometimes just "ships". In many series, a small spacecraft can even be called a "spaceboat" or "boat", and space-based missiles are in some stories also called "torpedoes".
  • Furthermore, the classes of ships in the Standard Sci-Fi Fleet are usually analogous to classes of waterborne ships, especially those used during World War II: Cruiser, Battleship, Destroyer, Frigate, etc. Good luck finding a Space Schooner or Space Canoe — though they have shown up.
  • Spacecraft even have "lifeboats" — generally called escape pods or something similar — despite the concept being largely impractical in case of realistic space travel. Though softer sci-fis can justify it with advanced technnologies.
  • Some works of fiction blur the line between spaceships and oceangoing vessels even further.
• Space is two-dimensional. Spacecraft tend to behave like actual ships floating in water, almost always navigating along the horizontal plane and rarely seen in any other orientation other than "upright", unless they are "sunk". Viewscreens are also almost always two-dimensional, when displays for battles at least should be three.
• Space has friction.
• Habitable planets are scattered across the Universe just like islands in a huge unexplored archipelago. Spaceships generally need to stock up supplies and energy on board between travels (some with sufficiently advanced technology just need solar energy to reload batteries though).
• Planets are the main objective of warfare, just like the dry land was in naval wars. They have multiple uses (resources, strategic location, habitable environment), but they are always the primary target in space, even if said resources would be more abundant in, say, asteroids.
• Space militaries almost always use naval ranks, as opposed to army ranks or the RAF system, and soldiers stationed in space are usually called "marines", e.g. the "space marines" of Aliens, Doom, Marathon, StarCraft, etc. Some works go all the way to calling Space "Black Water", as opposed to "Blue Water"(Oceans/Seas) and "Brown Water"(Rivers). Starship Troopers did not call its soldiers marines though it could be argued that it established the archetype for later space marine forces. Even in real life, space explorers are called "astronauts" and "cosmonauts" (see Real Life).
• Spaceships have a bridge with a big window in the front that looks out on space and is usually at the front or top of the ship. The decks of the spaceship will be parallel to the direction of flight.
• Spaceships have a very noticeable "top" and "bottom". Cockpits, conning-towers, communication dishes, weapons etc. will mostly be on the "top". The underside will be smoother, often punctuated only by a "bomb-bay" style docking hatch. The top is always oriented with regard to a universal definition of "up" that all space-faring polities seemingly accept. This could be justified for vehicles designed for atmospheric flight and landing, but makes no sense for orbit-to-deep-space-only ships.
• Space is chock full of whales.
• A spacecraft can be caught in an "ion storm" or the like, which will toss it hither and thither and ultimately run it aground on a strange exotic uncharted planet. ^note Ion storms are a real phenomenon, but they don't work like ocean storms; an ion storm is simply an unusually intense burst of solar wind.
• Space Clouds can hide your ship like an ocean fog.
• In space, hovering things have to move up and down slightly.
• Piloting spacecraft between asteroids is often compared to navigating boats and ships across the waters between rocky islands and islets within an archipelago on Earth.

In Space Opera, Science Fantasy and Steampunk Fantasy genres, writers are fond of filling Space with aether streams and solar winds, even magical ships with Solar Sails that literally "sail" through the Void.^note Solar winds and sails are an actual thing. Bill Nye, for one, took part in a program that launched a small craft into space that, once up there, used a solar sail (essentially a large mirror made of mylar) to 'catch' the minuscule pressure imparted by reflected sunlight. Solar winds, streams of electromagnetically charged plasma emitted by stars, provide orders of magnitude less "push" per surface area than the light pressure used by a reflective solar sail, but can also be used for propulsion with very different setups known as electric sails and magnetic sails. Rather than being driven by the impact of particles against physical sheets of material, these use "virtual sails" of electromagnetic field generated by large antennae to catch the electromagnetic "push" that drives the solar wind. Prototypes have been successfully tested, and while simple reflective solar sail is simpler and requires no internal power, electromagnetic sail's have numerous advantages including lower weight, higher acceleration, and larger operating ranges from a star. In those cases, you may find you can even breathe in Space, and if you're lucky you can even ignore the vacuum. Characterization and plot may also come straight out of the archetypes created during the era of Wooden Ships and Iron Men as well — including intrepid explorers, lost colonies, an exotic beauty in every port, Space Pirates, and sightings of the majestic Space Whale.

To some extent, Space Is An Ocean is a Justified Trope: not only was space thought to be some kind of fluid until the turn of The 20th Century^note The fluid was called "luminiferous aether"; physicists knew they couldn't detect it, but thought that they simply did not have the technical skill to do so at the time. We later discovered that the reason aether couldn't be detected is because it doesn't exist. This wasn't because they were stupid back then and couldn't imagine empty space — it's because they were sure light waves needed a medium (such as air or water) to propagate through, just as sound waves do. As it turns out, light behaves as both wave and particle, making it possible for light to travel through the vacuum of space like any other matter., but seafarers long ago evolved the organizational techniques necessary to safely operate a self-sufficient vessel in a potentially hostile environment for an extended period of time, and it makes more sense to adopt nautical administrative and logistic features (and the terms for them) instead of inventing everything from scratch.

As science fiction (and the aviation industry) has matured, Space Is Air has become a complement to Space Is An Ocean. Typically, large ships like The Battlestar will be based on naval craft, while smaller craft like the Space Fighter will be treated like aircraft. The two are not mutually exclusive — far from it, applying the tropes to different vehicles allows writers to recreate World War II (particularly the Pacific theater, with its pioneering of large-scale naval aviation) Recycled IN SPACE, which is pretty cool, as it allows using the tactics of the Old-School Dogfight and having to close to broadside range with capital ship guns. Land transport metaphors tend to fall flat. Elements of road vehicles are generally Played for Laughs; if a spacecraft has a manual transmission, it's a sure sign that Rule of Funny is a prime consideration. There is, however, a small but generally serious set of aversions (some listed below) that imagine space as a railroad instead — ranging from literal portrayals of trains in space to plots that take their inspiration from real-life railroad history.

Lots of speculative fiction in all media depict spaceships designed to land on water, since an ocean provides what amounts to an infinite runway with a similarly infinite capacity for absorbing the heat of re-entry. Some examples include the Bebop from Cowboy Bebop, the Seeker from David Brin's Startide Rising, most of the Space shuttles in Jerry Pournelle's CoDominium series, and the actual Apollo spacecraft sent to the moon (as well as the Mercury and Gemini spaceships that preceded Apollo) as well as the Huygens probe sent to Titan, Saturn's largest moon^note This one not for that reason, but instead because it was not known if it would land on solid terrain or a (methane) ocean. It found the former.

In more realistic takes on this trope, spacecraft may be likened to submarines instead of surface ships. There are a number of similarities between the two that make such a comparison useful:

• Both move in three dimensional space.
• Prolonged exposure to space (or water...you get it) outside the vessel can be deadly (if the sub is currently at depth).
• Visual displays of the outside environment are less than useless, and hence submarines and spacecraft tend not to have windows (both space and the briny deep are inky black).
• Submarines firing torpedoes is a decent analogy to semi-realistic space warships firing missiles.
• Unfortunately, there are still a few significant points of differentiation: Stealth in Space is much harder than staying undetected underwater, and space whales, while cool, require some hand waves.

Finally, while not technically Truth in Television, this trope may well become so out of sheer cultural inertia; if it didn't become so as soon as NASA started naming space shuttles right out of maritime tradition. There's even a test shuttle named Enterprise (a case of Defictionalization). There is also the fact that the orbits of most of the planets of The Solar System have an inclination of plus-or-minus 3° from a particular plane (the "ecliptic plane"),^note With Pluto demoted, Mercury is now the only exception and even its inclination is only 6.3°, although large bodies beyond Pluto and Batygin and Brown's theoretically-possible "Planet Nine" have orbits at very high inclinations (up to 30°) to the ecliptic plane. and that the majority of the star systems within The Milky Way Galaxy spiral arms are within 1° of the plane of the galactic disc,^note applies to the arms only, not the bulge or the halo, though said invariable ecliptic plane is not coplanar with the galactic disk.

Related tropes:

• 2-D Space
• The Internet Is an Ocean
• The Sky Is an Ocean
• Space Is Air
• Space Sailing
• Sand Is Water
• Water Is Air

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Examples:

Anime and Manga

• Infinite Ryvius: The series takes place after the Solar System is given a Negative Space Wedgie. The result is the "Sea of Geduld" (from the German word for "patience"), a nebula-like cloud engulfing the bottom half of the ecliptic plane. Ships that go too far — "deep", you might say — inside are crushed by the radiation and gravity anomalies, unless they're built to withstand the "dive". In other words, submarines in space.
• Leiji Matsumoto provided some of the most literal examples of this trope known to anime, as well as some of the oddest subversions.
  • Space Pirate Captain Harlock is steeped in nauticality: the main title song references the "Sea of Space", the eponymous space pirate's ship Arcadia has a sterncastle, with a Skull and Cross Bones pirate flag hung above it (and there's actually a device made specifically to move the flag as if there was wind). The ship is steered with an old-fashioned wooden steering wheel, and Harlock has, on occasion, sailed her on and below an ocean. Harlock's friend Emeraldas' ship Queen Emeraldas is a literal ship, suspended from a zeppelin.
  • In Space Battleship Yamato, Earth deliberately refits old (as in WWII-vintage) battleships as starships, and even continues to paint anti-fouling paint on them below the "waterline." The paint, however, makes sense, as the ship is intended to still function on water. Almost all the space combat is two-dimensional as well until a battle in Season Three where the Yamato attacks from below the plane of battle, spinning on its fore-to-aft axis to shoot enemies on all sides.
  • Space Battleship Yamato 2199 takes this almost literally but justifies the design of the ship as a method of camouflage during construction. However it regularly averts 2-D Space with Yamoto being attacked from below or surprised from above...then again it also has sub-space submarines.
  • In Galaxy Express 999, and The Galaxy Railways, though, space is a railway.
• Gundam:
  • Mobile Suit Gundam mostly avoids this territory (or goes to great lengths to justify it), White Base still has a big, old-fashioned and suspiciously nautical steering wheel on the bridge. The same goes for both the Musai-class cruisers and Gaw-class carriers.
  • Deserving special mention is Mobile Suit Crossbone Gundam, which has no less than two different ships designed to look like galleons, the Mother Vanguard and its sister ship, Eos Nyx. There's a seeming justification in a later manga, where one character says "Well, if we're going to be Space Pirates, we might as well run with the theme!" But the fact is that Mother Vanguard was designed by an entirely separate faction, one that tended to be aristocratic and knightly rather than piratical.
  • Avoided completely with Mobile Suit Gundam Wing, for all of the talk about indestructible Gundams, there was little to no space warships (except for fragile Mobile Suit Carriers which did not pack much in the way of armaments) and Mobile Suits attacked from Space Stations and Asteroids.
• Night on the Galactic Railroad: The travel mode is a train.
• The opening in Outlaw Star gives a narration in most episodes heavily relating space to being an ocean. Also in one episode their ship rides a stream of aether through space.
• Sol Bianca takes this one step further, in that the eponymous ship enters and exits hyperspace like a submarine diving or surfacing, complete with waves.
• In Starship Operators, the ships are on the same scale as battleships and (usually) fight like battleships. Two "stealth ships" are called "space submarines". Whenever any ship is destroyed, it's reported as having been "sunk".
• Super Robot Wars: Original Generation used Army ranks, while using terms that seem to be a combination of nautical and atmospheric flight along with some new ones. This could easily be explained by the fact that star travel is still really quite new — they have some orbital colonies, a base on the moon, and a space station in the asteroid belt.
• Tengen Toppa Gurren Lagann:
  • The Cool Starship suddenly sinks into a literal space ocean.
    "The Chouginga Dai-Gurren is going to sink!"
    "Sink? This is space! Why would there be an ocean in space?!"
    "It seems that the waves of ultra-dense space are pushing us down!"
    "Yeah. Like I said. WHY THE HELL ARE WE SINKING IN SPACE?!"
  • In this case, it was supposedly space so condensed that it acted like water. This included things like pressure. In fact, when that pressure resulted in the super-condensed space punching holes in the hull and "flooding" the ship, they decided that it was more accurate to call it "spacing" than flooding.

Comic Books

• Fantastic Four: Taken very literally in an early issue. There's only time to send one of the Inhumans to rescue Reed, who's stuck in the Negative Zone; Black Bolt chooses Triton, the merman, because space is like an ocean.
• The French graphic novel series, HK has the submarine route, as spacecraft here look like giant robotic whales and sharks. Whilst you don't see them battle each other, their decks are arranged in parallel like a submarine, and they land in bodies of water at harbors.
• Superman story The Living Legends of Superman: In the 21st century, astronauts are naval pilots serving in the navy and are called sailors. And their ships are explictly compared with ships floating "on the oceans of Earth".
• One French comic took the Recycled In Space route with Moby-Dick: the whalers become Asteroid Miners, the harpoons become ten-megaton nuclear warheads, the giant squid is a white dwarf, and Moby Dick is a sentient comet.
• Wonder Woman:
  • Wonder Woman (1942): The concept that space is ocean-like informs the design of Uvo's fleet of spacecraft which manage to look both fish-like and like modified submarines.
  • Given a nod in Wonder Woman (1987) where all of the Sangtee Empire space ships, from fighters to freighters, look like mechanical fish. The only exception are their giant space faring cities which instead look like cities in giant bubbles.
• X-Men: The Starjammers fit this trope.

Fan Works

• Twillight Sparkle's awesome adventure: There are even space sharks.

Film — Animation

• Treasure Planet has spaceships that have big honking sails on them. The characters are not exposed to outer space in those ships, but are rather in a kind of backwards universe where normal physics do not apply uniformly. There's even a black hole that's treated as a whirlpool.
• WALL•E:
  • The Axiom's autopilot, who is literally the ship's steering wheel, turns so that the ship tilts and everybody slides across the floor.
  • The captain has a typical cruise liner captain's hat and jacket, previous captains as seen on the picture wall and in the BnL ads have the full uniform. The Axiom itself resembles a giant stylized ocean cruise liner.
  • In BURN-E it is revealed that the ship has actually tilted several degrees to one side. Not that it makes much sense, but it was pretty cool.

Film — Live-Action

In General:

• Inverted in the peculiar slew of movies that came out in 1989 that are basically Space Isolation Horror films, except set deep underwater, instead of in space.
  • The Abyss is probably the best-known of the bunch. It was a first contact Humanity on Trial type movie, except instead of space aliens it was a kind of sci-fi take on merpeople.
  • Leviathan (1989) was more or less Alien but in an underwater mining station instead of a spaceship.
  • DeepStar Six, meanwhile, was also basically Alien but in an underwater military outpost.
  • Lords of the Deep did a similiar first contact story as The Abyss but it was a lot dumber.
  • The Rift (which came out in 1990, a year late) has alien-like monsters lurking in an air-filled cave deep beneath the ocean floor.

By Work:

• It is noticeable, at the beginning of the film Alien, that as the Nostromo leaves planetary orbit, it does so to a swelling soundtrack reminiscent of a classical nautical adventure movie — the music evokes a tall stately sail-ship leaving port rather than a beat-up cargo ship setting off into space.
• Walt Disney's movie The Black Hole is a version of Jules Verne's classic novel 20,000 Leagues Under the Sea set in space. The Palomino was portrayed as a vertically-arrayed vehicle, and given the FX of the time the first half an hour of the movie makes a game attempt to portray a crew operating in free fall in a spacecraft that actually looks somewhat plausible, given FTL. It's an odd contrast to the rest of the movie.
• Though the film The Fifth Element has very few (and even less relevant) space aspects, it takes this trope to its logical conclusion: the luxury space cruise liner Fhloston Paradise is shaped like a steam paddle boat, and has a classical nautical steering wheel to make course corrections. The "borders" of the Solar System also have floating buoys in a single plane.
• In The Man From Planet X an astronomer says, "The only difference between water and space is a matter of density."
• In Man of Steel, Zod's viral message refers to him crossing "an ocean of stars."
• Star Wars. Though many of the films' space battles would be incomprehensible if they took full advantage of 3D space.
  • Where the concept is taken to its reductio ad absurdum endpoint in Attack of the Clones where Obi-Wan Kenobi is forced to dodge seismic charges (read: depth charges) that make a loud "sonic" boom in a vacuum and send out a horizontally expanding shockwave.
  • The space battle that opens Star Wars Episode III: Revenge of the Sith takes this to an extreme, with kilometres-long spaceships side by side, firing broadsides at each other like ships of the line from the Age of Sail. Any doubt as to what the scene was trying to evoke was removed when you saw the gun crews loading and firing their giant blaster cannon through force-field gun ports. There's no excuse for the gun crews and gun ports, but the side-by-side combat is excusable: the battle takes place in the orbit of the Republic's capital planet. The attackers are not there for conquest but a raid and kidnapping; for that they have to get close to the planet to land ground troops safely.
  • In Return of the Jedi when Rebel vessels and Imperial Star Destroyers trade blasterfire during the final climactic space battle, with fighters streaming past in the foreground. This is justified however, in that the Rebel fleet is being fired on — with devastating results — by the Death Star. Their best chances at survival is to close in to short range with the Imperial Fleet. That way, the Death Star can't shoot at them without hitting the Imperial Fleet. As Lando says to Admiral Ackbar "Maybe we can take a few of them with us!"
  • Star Destroyers seem to array most of their guns in a top-turret and broadside position, making them comically vulnerable to anyone coming in from behind or below them.
  • This is abused in The Clone Wars when Ahsoka orders her ship to face the bottom at the enemy, thus rendering all damage to non-vital areas of the ship. (The concept being taken from The Thrawn Trilogy.)
  • The idea of giant space-dwelling "sea" monsters is also used throughout the franchise, resulting in creatures such as the nebula-dwelling neebray mantas in The Clone Wars, the purrgil (octopus-tentacled Space Whales in Star Wars Rebels) and the titanic, jellyfish-like summa-verminoth in Solo. Solo further features the Akkadese Maelstrom — the summa-verminoth's home — a perpetual space storm filled with roving carbon-bergs and a gravity well analogous to a giant whirlpool, making it effectively a space version of Scylla and Charybdis from The Odyssey.
• This Island Earth. Even the title is an example. Actually, during the space travel scene, the alien UFO does a very non-nautical manuever to dodge an asteroid, tilting right 90 degrees while gravity inside the ship remained the same.
• The film version of Wing Commander, ridiculously bad as it was, did do an interesting variation on this trope. In it, space was like an ocean, but spaceships were more akin to submarines than sailing ships (to the point that the crew was told to make no noise to avoid detection). Missiles had to be loaded into great honking tubes after the auto-loaders were said to have broken down from battle damage, they had depth-charge-like weapons.
  • Additionally, the missiles had to be fired manually by the loading crews on command from The Bridge instead of a single button on said bridge. Interestingly, the final space battle between the Tiger's Claw and a Kilrathi battleship ends up looking more like a surface naval battle with the Tiger's Claw forcing the Kilrathi ship to come by her side and then opening up with a broadside.
  • The Space Fighters, though, looked more like World War II fighters with a computer and a HUD and wouldn't look out of space with propellers on the front. They also, for some reason, include jump drives, even though they're never expected to perform jumps. Oh, and their on-board computers appear to have tons of data, including the identities of top-secret high-ranking operatives. The Kilrathi should've been trying to capture one of those computers instead of a Navcom AI.

Literature

• Used in Accelerando by Charles Stross to justify shooting digital communist lobsters into space. They want to return to the ocean, but as digital entities that's not possible. Putting them in a space ship's computer and launching it into space, however...
• Airborn: In the final book, Starclimber, space and its native life are portrayed as analogues to an immense ocean and marine life. This includes "space plankton", "barnacles" which grow on the cable of the space elevator the characters are using, and immense, bioluminescent, eel-like Space Whales. The characters' speculations about the nature of the cosmos cast planetary system as shallow waters and deep space as the open ocean and its abysses, where creatures much larger than the ones they saw might lurk.
• Alexis Carew leans really hard on the Wooden Ships and Iron Men IN SPACE! styling. Darkspace is treated as the open sea, complete with shoals and storms. Space Sailing is done by harnessing its currents, and ships navigate by dead reckoning and fight in broadside duels using hand-loaded single-shot laser cannons aimed by eye (because darkspace dampens electricity and otherwise resists any attempts to study it). The landlubber protagonist is also often befuddled in the first book by the constant use of archaic naval terminology:
  Alexis: (reading the name of a structural segment off her tablet) "Forward-twelve-port, first futtock"? Now you're just making things up!
• The novel Berserker Fury is the World War II naval Battle of Midway Recycled IN SPACE!! The AI robot ships are the Japanese and humanity is the Americans. Complete down to the planet named 50/50 (Midway), the "space carriers" Venture (USS Enterprise), Stinger (USS Hornet), and so on. They even broke the Berserker code, like the USA broke the Japanese Purple Code.
• Gene Wolfe's Book of the New Sun relies heavily on this. Space crafts are described as ships, the crew are called "sailors" and so on, to the point where it's often not clear whether the narrator is talking about seafaring or space travel. In the coda Urth of the New Sun, the interstellar space ship turns out to have masts and sails, and to apparently be made partly of wood.
  • In The Book of the New Sun, the ships of the Hierodules travel through time and between Universes on mirrored sails. The terminology used is nautical to the extent that Gene Wolfe expresses frustration that Severian draws no distinction between nautical and space vessels. Indeed, sailors themselves apparently find the two sorts of vessel interchangeable for employment.
  If a distant continent is as remote as the moon, then the moon is no more remote than a distant continent.
• David Drake:
  • The RCN series is loosely based off the 18th century British navy, complete with spaceships that travel through hyperspace using sails. However, the sails are handled fairly realistically: stripping a ship's sails with a plasma cannon is a quick and easy way to keep it from escaping into hyperspace, the sails need to be furled and stowed before entering an atmosphere, and when deployed, interfere with the ships's realspace maneuvering and combat. In the same way that Honor Harrington is Hornblower/Nelson IN SPACE, the RCN books are Aubrey-Maturin IN SPACE, with Daniel O'Leary in the role of Jack Aubrey and Adele Mundy as Stephen Maturin (only with her being the ship's comms officer rather than its surgeon).
  • Drake's Reaches novels (Igniting the Reaches, Through the Breach, and Fireships) are Hakluyt's Voyages crossed with the adventures of Sir Francis Drake during the wars with Spain. It's 16th century exploration & piracy IN SPACE.
  • The Citizen Series: Habitable planets are regarded as islands in the "sea" that is the Continuum, a sea which has currents that can speed or slow travel. The Bight between the Cutter Stream Colonies and their parent Home World, Brasilia, stands in for the Atlantic Ocean in particular, with mentions of a circular Continuum current that corresponds to the Easterlies and Westerlies. Unusually, though, the series also includes "trackways" that can be built across the Continuum to artificially stabilize currents (space roads), and Continuum combat behaves like World War I and World War II dogfighting.
• H. P. Lovecraft's The Dream-Quest of Unknown Kadath provides and early and very literal example of the trope. In the Dreamlands it is possible to reach the outer space simply by sailing over the edge of the world in a craft capable of surviving the rushing waters, and going on straight. The protagonist is kidnapped by a sinister crew of semi-human slave traders and taken captive to the Moon in this manner.
• A note: despite 'Navigators', and a feudal setting, Dune space travel is not in the least an example of this trope — the Holtzmann effect, while never properly described, seems to work more like teleportation than anything else (huge distances are moved 'in the blink of an eye', actual 'sailing' is negligible on any scale, and space warfare non-existent apart from orbital skirmishes due to the Guild (who are neutral) monopoly on interstellar travel.
  • There are elements of this in the Legends of Dune prequel novels with disputed canonicity, which features plenty of space battles between the League Armada (later Army of Humanity) and the Thinking Machines. Unusual for this setting, though, the military ranks in use are all made up and, in fact, change throughout the trilogy. For example, the equivalent of a general would be a Primero (League Armada), a Bashar (Army of Humanity), and a Caid (post-Jihad). These fictional army ranks are also used by ship officers. Strangely, the novels have generals command both ground and space battles. One would think these would be two completely different types of combat, requiring different skillsets (you wouldn't put a naval admiral in charge of a ground battle or an army general in command of a fleet, would you?).
• In Ender's Shadow, Bean arrives at Battle School and goes exploring. He remarks: "Most poles and ladderways would merely let you pass between floors — no, they called them decks; this was the International Fleet and so everything pretended to be a ship." Later on in Shadow Puppets Ender's father, after hearing a reference to a "dry dock", asks if there is also a "wet dock". Dimak's response is: "Nautical terminology dies hard."
• The Expanse embraces the trope of stellar navies with both the United Nations Navy and the Martian Congressional Republic Navy, each with their UN Marines and MCRN Marines respectively. The decks of the ships are perpendicular to the direction of travel, with thrust from acceleration and deceleration providing the g-forces used to keep people on the deck (and magnetic boots when not under acceleration).
• Wet-navy terminology is heavily used in The Flight Engineer, as might be expected from a trilogy coauthored by James Doohan. Space itself is not an ocean, however, and at one point the series delivers a hilarious Take That! to the Star Trek episode where Roddenberry confused the Enterprise with a submarine.
• Played straight in Future History, complete with Space Clouds, Space Friction, and a Standard SciFi Fleet.
• Harry Harrison:
  • Harrison makes an effort to avert this (to an extent) in Starworld, although the novel only has one space battle. An engineer shows the protagonist (also an engineer) a clip of a space battle from an old sci-fi movie and asks him to point out everything in it that's wrong. The protagonist can't do it, as he knows absolutely nothing about space combat and space travel in general. Among others, the engineer points out that the ship in the movie maneuvered like an airplane (banking hard), was able to stop on a dime to hide behind a planetoid, was using energy weapons (while lasers and plasma weapons exist in this 'verse, they're only useful at relatively short ranges), and had windows. Actual space combat is explained as between ships many kilometers away from each other, and the only weapons being used are missiles (both conventional and nuclear), although they are often deployed as screens (an impromptu mine field) ahead of the fleet. The reason the engineer needs the protagonist's help is to help him iron out the last few kinks on the rebels' secret weapon — a mass driver using plain old metal balls as ammo. They also have short-range autocannons firing rocket-propelled bullets. The entire Curb-Stomp Battle is ridiculously short. The Earth fleet gets crippled by the mass drivers' opening volley with the autocannons delivering the coup de grâce.
  • Harrison made a habit of this. In Space Viking, the structure of a spaceship is discussed in some detail, with the command center deep inside. During the space battles, the crew are well aware that attack can come from any angle, and keep eyes-high accordingly. Captain and other crew ranks are used.
• While the design of his spacecraft reflect a working knowledge of engineering, almost every book Robert A. Heinlein wrote that took place aboard a spaceship assumed nautical, particularly Naval, discipline and traditions, from Laz & Lor's stick-on Captain's insignia to Captain Hilda of the Gay Deceiver. This might have had as much to do with Heinlein's own Naval career as anything, although it has undoubtedly shaped the trope to some degree.
  • This is especially noticeable in his "Juvenile" novels that involved commercial or military space travel such as: Between Planets, Citizen of the Galaxy, Farmer in the Sky, Space Cadet (Heinlein) and Starman Jones.
• The Honor Harrington novel series technology was set up explicitly so author David Weber could do Horatio Hornblower IN SPACE, with formations of spacecraft blasting away broadsides at each other and even using "gravitational sails" to navigate hyperspace (hyperspace itself having "currents", "waves" and areas just too damn stormy...err, gravitationally random, to move through safely).
  • The overall plot was nice for most who knew their naval history, saying oh X is Y and so forth. Then Napoleon got nuked ...
  • Echoes of Honor is basically a retelling of CS Forester's Flying Colours — only much, much bigger. Instead of escaping with twenty prisoners in a dinky cutter like Hornblower, having destroyed three small rowboats sent to chase him, Honor escapes with half a million prisoners and an entire battlefleet, fighting major battles on the way.
  • An article describing various literary examples of "Hornblower in Space" (including Weber's) can be found here.
• Alan Dean Foster's Humanx Commonwealth series makes liberal use of naval metaphors in its space travel, including fleets of private merchant vessels that deliver goods from planet to planet on a monthly schedule, and "passenger liners" that do the same for people. It retains some of the metaphors of naval combat, although not all: starship combat is generally done at great distances with lightspeed or FTL weapons, but the notion of a Standard Sci-Fi Fleet along with Space Fighters remains intact. The series does not, however, make the mistake of having spaceships look like oceanfaring vessels; quite the opposite: a KK-drive starship resembles a toilet plunger or a wineglass stuck onto an oblong main hull; the end of the "plunger" is the fan for an Artificial Gravity generator.
• Played straight in Into the Looking Glass novel Vorpal Blade by John Ringo. Humanity's only spaceship is a converted nuclear submarine. He also speculates that there are "standing gravity waves" in interstellar space; the space equivalent of oceanic currents.
• In Lando Calrissian and the Starcave of ThonBoka, there is a species of giant rays that live in vacuum and consider it an ocean. The opening passage of the novel describes space as though it were an ocean.
• This is one of the defining characteristics of the Larklight book series. Not only do (most) spacecraft strongly resemble sailing ships, space is also populated with a wide variety of fish that even grow increasingly stranger the further away they are from the sun, much like deep-sea fish on Earth.
• In The Lost Fleet series, there is a Space Navy with a Standard Sci-Fi Fleet using 20th-century ship types (e.g. destroyers, cruisers, battleships). Enlisted men and women are often called sailors. And even terms like "port" and "starboard" still survive. However, during the Battle of Kaliban, a civilian character asks Geary about the use of these terms as well as "up" and "down" in space, especially since the main body of the fleet is, at that point, inverted from the perspective of the rest of the ships. Geary explains that "up" and "down" are conventional directions with respect to the ecliptic (as long as it's determined ahead of time which hemisphere is "up" and which one is "down") of the current star system. "Starboard" is towards the star (Geary even mentions that attempts to replace it with "starward" failed), while "port" is away from the star. When asked what happens when ships are far from any star system, Geary replies that this never happens. Since the only known methods of FTL Travel involve either the use of Hyperspace Lanes or a Portal Network, ships don't normally go out into interstellar space.
  • One thing that no one asks is what happens when multiple ships are already facing directly towards or away from the star, but on vastly different vectors.
• Moby-Dick: Ahab says the line "...where in her murderous hold this frigate earth is ballasted with the bones of millions of the drowned..." comparing the planet itself to a ship sailing through the cosmos.
• Peter F. Hamilton's spaceships (especially in The Night's Dawn Trilogy) are spherical, and for a reason: Adamist (that is, non-biotechnological) starships use a "ZTT drive" to jump across lightyears. The drive creates a wormhole that, like a black hole, has a spherical event horizon. Activating the drive while the ship is in non-spherical mode (that is, with sensors extended) will lead to everything beyond the event horizon being torn apart and compressed to fusion density. BOOM!
  • Edenist voidhawks, however, are far superior to Adamist ships in every way — including FTL travel — due to the fact that they are made of "bitek" (a biological material). Voidhawks are lenticular in shape rather than spherical. Blackhawks — bitek starships with Adamist commanders — on the other hand can be pretty much any shape.
  • Hamilton uses many Space Is an Ocean tropes, but in a manner that is far more 2001 than Star Wars.
• In Night Train To Rigel by Timothy Zahn, space is actually a railway system. Go figure.
• The Silmarillion plays this trope straight with Eärendil, an actual sailor who ends up sailing the celestial oceans in an actual ship — seen and interpreted as a star.
• In Michael Flynn's Spiral Arm series, this is played with: the terms have clearly been lifted from ocean ships, but they mean very different things.
• Star Carrier:
  • Much like Battlestar Galactica (2003), below, the series relies on 20th- and 21st-century nautical metaphors rather than ones from the Age of Sail. For example, it's not a bridge or quarterdeck, it's a CIC, and the commander of the fighter wing has the title "Commander, Air Group" (which gets lampshaded, and explained as the old name sticking despite efforts to update it), CAG for short. (Note here that the author served in Vietnam as a Navy corpsman.) The America's CIC is also placed in a better-protected location, in the habitat rings aft of the giant mushroom-shaped shield cap at the bow. Even the Navy SEALs are still around, except the acronym was updated to SEALS (the second 's' being "space").
  • Later books introduce an alien race called the Slan, whose primary sense is auditory and who use echolocation to "see". This has drastically affected their development as a culture. Since they primary live in caves, they treat the surface as a gigantic cave. They're unable to "see" stars, since their light-sensing organ is far too weak for that. They didn't even reach space until given the technology by another race. Even then, they have a hard time comprehending the idea of space, interpreting it as a vast airless cave that requires special vessels to move across.
• The Starwolf series by David Gerrold was written as a Sub Story IN SPACE!, because the vast distances involved means all the action is confined to Sensor Suspense or the tensions created among the crew who are confined inside the ship.
• Arthur C. Clarke's short story The Wind from the Sun. This is an interesting case because it manages to evoke the feel of ocean travel in space despite being a fairly realistic and hard work. It is a story about literal Space Sailing — using perfectly realistic Solar Sails, shown to behave the way one would expect given Real Life physics.
• Generally averted in Harry Turtledove's World War books and their sequels. When humans start building spacecraft of their own, the ranks they use are Army ranks, and ship commanders are called Commandants. Even the use of the word "ship" for a spacecraft is lampshades by a Chinese peasant woman, who hears a male of the Race refer to the craft in this manner, wonder why he says that about a "plane-that-never-comes-down", since it flies instead of swimming. It's also strange that a race that has never had a wet navy in their history (due to being from a desert world) would call a spacecraft a "ship".

Live-Action TV

• Downplayed in Andromeda. While it certainly includes some of the typical trappings of a Space Navy, such as spacecraft being called "ships" and their commanding officers being called "captains" (reporting to admirals), the ships themselves use Artificial Gravity to fly around and maneuver like fighter jets.
• Babylon 5 did dispense with the atmospheric flight analogies, but retained many of the naval ones. It is even mentioned on-screen in the movie "A Call To Arms" that the command decks of Earth ships are traditionally modeled on a submarine. Probably because submarine warfare is the closest analogue to space combat you are likely to find until it actually exists: the arena is 3D, visual targeting is almost always useless, and a small hole in the ship is a major problem rather than a minor inconvenience. Another strange thing is the classification of ships. It seems that the newer, more powerful ships in EarthForce are called destroyers (Omega, Warlock, Victory), while the older wartime ships are called heavy cruisers (Hyperion) and dreadnoughts (Nova). This is despite the fact that destroyers are frequently larger than heavy cruisers or dreadnoughts. For example, the Omega is, basically, the old Nova with the addition of a spinning central section and less powerful but longer-ranged weapons.
• The modern Battlestar Galactica avoided many of the traditional Space Navy trappings, to replace them with the trappings of a modern US Navy aircraft carrier. A case of Shown Their Work, there are many details lifted straight from modern naval procedure and culture. Your typical viewer likely has no idea why engineering types are called "snipes" for example.
  • Perhaps most notable the CIC (rather than the 'Bridge') is deep inside the ship, with no windows to the outside. Others include use of the terms CAG and CAP.
  • Lampshaded in Face of the Enemy. When stranded in a Raptor with a non-operational FTL, one of the crewmen in Felix's group begins praying to Poseidon. One of the Eights on board is puzzled since they're a long way from water. He replies that they're in a ship so it's close enough.
• Doctor Who:
  • "Voyage of the Damned": The space Titanic is built to look just like the original, and even has a life preserver (as in the flotation device) on the front.
  • "The Beast Below": The Doctor realizes there is something wrong because of the lack of engine vibration — the assumption being that of course a spaceship would need engines constantly running to move through space. They don't need the engines because the ship is being moved via a Space Whale swimming through space.
    • Long-range spaceships are usually designed to accelerate for half of the distance (until the turnaround point) and then decelerate, so the engines are always in use. Now, Starship UK may not have had a set destination (and thus no turnaround point) but that's even less realistic: Picking a random vector and drifting is the worst possible way of approaching a star, let alone a habitable world.
    • Even if not needed for propulsion there would still be the need for power, lights, artificial gravity, etc.
  • "The Curse of the Black Spot": An Earth pirate is able to successfully fly the TARDIS because it is so analogous to his pirate ship. He can determine what parts of the control panel are the "compass" and "wheel" based entirely on his life experience as a pirate captain.
• The Expanse embraces the trope of stellar navies with both the United Nations Navy and the Martian Congressional Republic Navy, each with their UN Marines and MCRN Marines respectively. The decks of the ships are perpendicular to the direction of travel, with thrust from acceleration and deceleration providing the g-forces used to keep people on the deck (and magnetic boots when not under acceleration).
• Firefly made frequent use of the nautical metaphor, even though it was somewhat at odds with the style of the show as a Space Western. In particular, Mal will not stop calling the ship a "boat." "Wagon" wouldn't have had quite the same ring.
  • The Alliance cruisers in the series were designed to avoid this. The result is a ship consisting of four large vertical towers, with fighters and other craft launching upside-down off a flight deck at the "bottom" of the ship. It looked more like a mobile city than a ship. The smaller warships that appeared in Serenity resembled nautical vessels more, but that's likely because they're meant to operate in atmospheres as well as space.
  • From interviews and DVD commentaries, the feel of Serenity specifically was supposed to be submarine-oriented rather than ship-oriented, which does then make the nickname of "boat" remind one more of "u-boat" (a German word for "submarine" even if in English it's used almost exclusively for German World War submarines) than surface ships and boats. This was deliberately designed to contrast with the Alliance "floating cities" as a way of showing the concept of efficiency (submarine-like ships that don't waste any part of the structure) and decadent waste (alliance ships being designed to be impressive, but not efficient). This is best highlighted in the episode "Bushwacked" when Kaylee displays a willingness to take on the Alliance single-handedly for daring to call Serenity a junker — Alliance ships are the junk vessels to her because of their (dangerous) lack of engineering logic.
    • One aversion is the cockpit, which is located right and the front rather than on top, and leans far more towards an aircraft's flight deck than a nautical bridge.
    • Submarines are referred to as "boats" in the US Navy, too.
• The GoGoVoyager of GoGo Sentai Boukenger meets the same fate as the battleships in Space Battleship Yamato. At first it is a (VERY large) battleship which, naturally, reconfigures into a giant robot, DaiVoyager. At the end of the series, GoGoVoyager has been converted into a spaceship... quite badly, if the cockpit is any indication.
• Mystery Science Theater 3000 tended to vary in its depiction of space depending on which was funnier at the moment. In The Movie, the Satellite Of Love's controls were shown to be identical to a boat's helm, and Gypsy, piloting the satellite, was wearing a sailor's cap and singing a sea shanty.
• Inverted in SeaQuest DSV, whose premise was basically "The Ocean is Space".
  • The show pretty much ignores fluid dynamics whenever it's convenient and goes with the Water Is Air idea.
• In general, Space: Above and Beyond tended to have nautical metaphors for the larger craft and, like Battlestar Galactica, atmospheric flight metaphors for the one-person craft. The analogy seemed to be with an aircraft carrier.
  • Specifically, the capital ships in the series — Saratoga, Hornet, etc. — are all named after US Navy aircraft carriers, though with ground troops and their transports also aboard, the capital ships seem closer to present day amphibious assault ships. Notably, however, the Space is an Ocean analogy is not extended to the small transport craft, which are referred to by the decidedly land-based term of APC, rather than as "landing craft" (as they are often used to ferry troops to planetside from space) or simply, "transport."
• Stargate SG-1 and Stargate Atlantis avert this trope in some ways, but follow it in others:
  • Since the Stargate program is run by the U.S. Air Force, it uses more Air Force than nautical analogies. (And with official Air Force technical advisors, they generally get the details right.) For example:
    • One of the spacecraft in Stargate Atlantis was dubbed the "Puddle Jumper", an aircraft name (though it was called a Gate Ship by the original creators, as well as McKay, in two separate realities). Admittedly, there was another very good reason for calling it that.
    • The terms used to describe ships and their commanders follow Air Force conventions. For example, when hailing another vessel the commander might introduce themselves as "General Hammond of the Earth vessel Prometheus." This contrasts with the common science-fiction convention of referring to the commander as a Captain or Admiral and calling the vessel "USS Name", which would follow Navy conventions.
    • Prototype USAF starships and fighters are dubbed "X-301" and similar, following Air Force practice for experimental aircraft.
  • On the other hand, the show also demonstrates how deeply entrenched this trope is, in that all major Earth starships are named like Navy ships, and in the fact that they're actually called "ships" as opposed to "aircraft" or "spacecraft."
    • Since the characters of the Stargate-verse are quite Genre Savvy (in multiple instances comparing their spacecraft to those of Star Trek), one interpretation is that even for them, the idea of calling a spacecraft a "ship", the command center the "bridge", and the prison the "brig", are so deeply entrenched that it simply sticks. Or at the very least, the Air Force is aware that their 303s and 304s are more like aircraft carriers than anything else, and borrow some of the terminology.
  • In a possible reference to this trope, when Ba'al screws around with the timeline in Stargate: Continuum, the Navy runs the Stargate program in the alternate timeline instead of the Air Force. The original SG-1 are all slightly put off by this revelation. Which is a little strange, since this timeline's Earth does not have any starships.
• In UFO (1970), it appears that Space Is the English Channel given the number of Battle of Britain tropes it draws upon: Moonbase is the beleaguered sector airfield, SID (Space Intruder Detector) the RDF radar post, and calmly speaking young women (WAAF's) vector in SHADO Interceptors (Spitfires) against the anonymous alien invaders (German bombers). But given that the Moon takes 27.322 days to orbit the Earth, one wonders why the aliens don't just attack SHADO headquarters when the Moon is on the opposite side of the planet.

Music

• Not only is space an ocean in DAAS Kapital, but the spaceship of choice is a submarine!
• '39 by Queen, though it's more to draw an analogy between space exploration and the Age of Exploration. In fact it can be thought to be about actual sea exploration at the beginning. It starts out with terms like "the ship sailed into the blue". Space travel is hinted when "milky seas" are mentioned, then at the end we see that time dilation came into effect.
• Bruce Dickinson's "Navigate the Seas of the Sun" is a song about space travel.

Mythology

• The Ancient Egyptians actually did believe that space was an ocean, named Nuun.

Star Trek

• Star Trek made as much of the nautical metaphor as it possibly could.
  • A maritime tradition that survives in Starfleet is the tradition of ship's captains performing wedding ceremonies. Kirk, Picard, and Janeway all have this honor on the show, even saying the same words (presumably an official text for Starfleet captains): "Since the days of the first wooden vessels, all ship masters have had one happy privilege: that of uniting two people in the bonds of matrimony."
  • Star Trek: The Original Series
    • The fact that Dr. McCoy's nickname is Bones is also a reference to the sailing era, being a common period nickname for the ship's surgeon, short for "sawbones."
    • The episode "Balance of Terror" hyperextended the metaphor by presenting a cloaked ship as analogous to a submarine. The crew of the Enterprise has to be quiet while the Romulans are hunting them in a situation analogous to sonar.
    • In the episode "The Ultimate Computer," Kirk says, "All I ... ask is a tall ship and a star ... to steer her by." You ... you could feel the wind at your back in those days. The sounds of the sea ... beneath you, and even if you take away the wind and the water ... it's still the same. The ship is yours. You can feel her. And the stars are still there, Bones."
    • The ship uses whistles before some broadcasts on the ship's internal comms exactly the same as Navy ships do. Originally, in pre-modern times, the whistle was used to call all hands to the deck to hear the day's General Orders. Today, it's more to catch everyone's attention before the broadcast. This tradition was mostly dropped from later incarnations of the franchise.
  • Star Trek II: The Wrath of Khan: The Enterprise beats Khan's ship by maneuvering in 3 dimensions. Spock specifically mentions this, saying Khan is used to "old wars" and thus doesn't think in three dimensions, only two.
  • Star Trek VI: The Undiscovered Country: When the Enterprise interior is being picked apart from top to bottom the atmosphere as a whole subtly gives the impression of an actual naval vessel in space. The ship's bell even rings in a few scenes. The space battle comes off as two surface warships attempting to pin down a particularly stealthy submarine, presumably one that never needed to surface for air.
  • Star Trek: The Next Generation
    • In the episode "Allegiance," Picard sings "Heart of Oak," an old British navy song.
    • "Yesterday's Enterprise" shows what life would be like on the Enterprise-D if she had been designed as a dedicated warship, and the effect is pretty familiar to anyone who has served in a modern navy: crowded, utilitarian, and noisy — even aping the constant PA announcements in the background. If you listen closely, references to the ship's CIC can even be heard in a scene set in Ten-Forward, which is no longer a bar, but a place for the crew to gather and eat the Starfleet equivalent of B-rations.
  • In Star Trek: Generations, Worf's promotion ceremony is held in a holodeck recreation of a 19th century British Naval vessel, complete with period uniforms and a plank.
  • Star Trek: Insurrection: Picard's personal diplomatic craft is called a "yacht."
  • According to longtime Star Trek graphic designer Michael Okuda, illegible signage in the various series often referred to emergency escape pods as "lifeboats."
  • Star Trek: Deep Space Nine:
    • "Explorers" involves Captain Sisko playing Thor Heyerdahl in a replica of an ancient Bajoran ship powered by Solar Sails. Extra points to this one in that the spaceship has actual rigging — rigging that has to be altered manually like a sailing ship. Apparently the Bajorans invented interstellar flight some time before things like hydraulics, computers or mechanization ... They were working from one particular inventor's plans, and needed an exact duplicate to prove a point.
    • In "Playing God", Jadzia Dax straight up says that they "picked up some kind of subspace seaweed" while out in the runabout shuttle.
    • "For the Uniform" plays a modernised version. Due to the Defiant's computer core having been mostly wiped by a computer virus the ship has to be flown with a larger crew than is normally visible, with orders relayed from the bridge all over the ship and characters giving detailed instructions and echoing commands. The resulting cacophony of overlapping voices rather accurately captures what the CIC of a modern warship sounds like.
  • The film Star Trek Beyond kinda plays with this trope to the max during the climax when the USS Franklin flies straight into the drone swarm fleet. It visually looks like a rogue wave.
  • Extended Universe:
    • A Star Trek novel describes Starfleet regulations as being "copied from old US naval regs." While this book isn't canon, it does suggest that Starfleet was consciously modeled on an oceanic navy.
    • The "NCC" prefix of Starfleet ship registration numbers stands for "naval construction contract."

Tabletop Games

• Alternity: not only warship classes are modelled after Real Life naval ones, them as the Battle Cruiser (heavily armed and sacrificing armor in exchange for speed) being more or less like their sea equivalents, but also artwork of most of them gives them a well-defined top and bottom, up to having a citadel on the former.
• Attack Vector: Tactical tends towards the harder-than-diamonds end of sci-fi and therefore avoids directly copying mechanics from wet navy combat. However, the military organization structures are all over the place. Novaya Rossiya calls the space branch of its military the Artilleriya Kosmosa and refers to its starship crew members as "soldiers," their Shokoladki-class starships are even officially classified as "Space-Mobile Artillery Platforms." Meanwhile, the Caliphate of Medina based the organization of the Medinan Star Force on the Royal Air Force, by way of the Pakistani and Egyptian Air Forces, so their starships are classed as "Multi-Role Fighter," "Attack Spacecraft," etc. Olympia, Xing Cheng and Novo Brasil play it perfectly straight with their naval-style space forces and fleets of cruisers, destroyers and frigates, however.
• Battle Space, the space-combat game based in the Battletech universe, avoids most of these aspects. While played on a 2D board, ships act in 3D space, there is no friction so all movement must be countered by spinning the ship around and applying thrust, some larger ships (jumpships/warships) have ambiguous hulls to hide the bridge (though, it should be pointed out that every captain would have intel on all non-top secret ships, so this would be moot), and fighters, dropships, and a few landing craft are the only things that can enter the atmosphere without being destroyed. There are still many that are unavoidable (space travel times, ship class names), but most of that is handwaved as otherwise it would be horrendously boring.
• The implied setting for Fourth Edition Dungeons and Dragons includes the Astral Sea. Despite the Astral Sea being three-dimensional and possibly infinite, a "surface" exists that most creatures stay near out of instinct.
• Full Thrust is a truly great tabletop wargame, with great background fluff, realistic (semi-optional) "vector movement" rules, and a variable unit system — the game system measurements come with a suggested (very reasonable) scale, but is in the end explicitly left up to the players to decide. In one game, 1 Movement Unit might be a single kilometre, while in another, it might be a whole AU or more. 1 point of Mass might be the suggested 100 tonnes and scale linearly, or it might be 10 and scale logarithmically.
  • Best of all, the turns do not alternate; the players write down their movement orders for the turn, fire ordnance based on anticipating the enemy's movement, move their ships, resolve ordnance fire and then take turns firing the main ship-to-ship weaponry — all in the same turn! Makes the game a lot more realistic, and more about actual tactics than quirks in the rules.
• Mage: The Ascension has the Sons of Ether, techno-mages based around fringe, outdated, and/or pulp science, who have galleon-like Etherships whose sails catch "etheric currents." That Ethernauts tend to stand on the decks of such ships, dressed in nautical steampunk and firing lasers from cannons, is in line with the Etherite mentality. It also irritates their foes, as the Void Engineers are constrained by a 'no oxygen/waves in space' paradigm. ^note The straw that drove the Sons of Ether out of the Technocracy was the latter's decision to exclude Ether from the accepted Paradigm, which, among other things, took the Ocean out of Space.
• Space often seems very nautical in Rocket Age. There are pirates, fairly traditional navies and the great black beyond often seems more like an ocean to be crossed and explored.
• Space 1889: Justified. European countries have their regular ocean navies handle the liftwood ships and aether flyers and since liftwood is relatively new (less than twenty years ago) to the Europeans their shipbuilders mostly use nomenclature, technologies and techniques from the regular navy.
• The Spelljammer setting for Dungeons & Dragons has rather a lot of starships that look like sailing ships. This is because at the tech level of Dungeons & Dragons, major trading centers on planets are likely to be coastal or at least river cities. Many of the spelljammers are designed to be capable of landing on water, so they can use the existing facilities (docks, presence of longshoremen to act as temporary workers to load and unload cargo, large and thriving merchant community). It's also explicitly stated that since the only really essential piece of equipment is the jamming helm, for most cultures it's easiest to take a vessel you've already got lying around and slap a helm in it, and water-based cargo vessels tend to be significantly larger than land-based ones, so...
  
  Combat rules are based on 2D combat. There's no provision for soaring over or diving below another vessel. A valiant effort is made to justify this in the form of the "gravity plane": in Spelljammer, objects in space have... for some reason... a gravity plane, and gravity acts in a direction normal to this plane (from both sides, so it's possible to design a ship with decks on both the "top" and "bottom", though such a ship can't ever land on either land or water for obvious reasons). What's not explained is how the gravity plane "knows" to pass through the ship parallel to the decks instead of, say, perpendicular to them. There's also not just friction in space, but no concept of inertia whatsoever: no matter how fast you were moving last turn, if you don't use your movement points this turn, you don't move.
• Starfire has fleets of starships, with size classes named things like "light cruiser", "battlecruiser", "superdreadnought", etc., who cruise under constant engine power and always follow their noses. The Terran Federation Navy is run by admirals, who give orders to starship captains. Messages sent between star systems have to be delivered by courier drone, or in person, since radio signals can't travel through a warp point. And, of course, the game is plated on a flat map, which in the first edition was even blue in color.
• The Empire sourcebook for the old Star Wars d6 presents, in addition to classical SW ships as the Imperial Star Destroyer and others (an escort carrier, several types of cruiser, etc) based on wet navy ones, an "Star Galleon" — basically an armed and armored transport, don't think on a sailing vessel. Said ships do not follow Real Life ship classes, with (star) destroyers dwarfing cruisers.
• Transhuman Space for GURPS both uses and averts this trope. Set at the turn of the 23nd Century (2199-2205), in sci-fi universe that doesn't leave the Solar System, the United Kingdom's space forces are formed by the Royal Navy, while the Chinese are based on the Army Rocket Forces, and the American space force is an extension of the Air Force, who beat the U.S. Navy in a bidding war. So the UK forces use naval metaphors, while the others don't.
• There's an illustration for Traveller if memory serves right that features a space carrier with a flattop and a bridge to one side as if it was the sea equivalent.
• The Warhammer 40,000 spinoff game Battlefleet Gothic is a great example of this. The game and the ships in it joyfully embrace the coolest aspects of naval combat through history, with vast hypertech vessels using Napoleonic broadside-based tactics of lines and crossing the T, ancient Greek-style ramming and boarding actions, early 20th century torpedoes and torpedo boats... Eldar ships even have solar sails, need to be at the right angle to the sun to work most effectively, and sometimes tack.
  • Rogue Trader runs with this — there's more detail on life in a spaceship, and it's surprisingly similar to living on an Age of Sail vessel (only GRIMDARK, of course). It's also got that lovely submariny touch of Silent Running for stealth purposes — in fact, this is stated to be the main way to disengage from a battle. Ships have a Fore, Aft, Left and Right side — no love for top and bottom...
    • The Horus Heresy supplements by Forge World take this even further, introducing a bewildering array of ship types, in addition to the Standard WWII, with names taken from the Age of Sail, such as barques, arks, carracks, galleons and galleass. How a 16th century combined sail and oar propulsion ship translates to space is best left to the imagination, but apparently it is favored by Rogue Traders and approaches a Battleship in power, being able to clear the orbit of a planet and launch a counter-invasion on its own.

Video Games

• Castle of Shikigami III has this line from Canon Foreigner Reika Kirishima:
  Reika: Space is an ocean of space.
• Conquest: Frontier Wars has a Navy-life stucture with space battle ships and even a space aircraft carrier, other units do look more like airplanes. The Space Is an Ocean idea is further emphasized by the Celareon ships looking like Space Whales.
• Ecco the Dolphin: At the end of the game, Ecco swims from Earth to Vortex, a planet in the Pegasus constellation.
• Empire Earth:
  • The sequel treats space as a Setting Update of ocean maps: planets are big round "islands", with space docks and space turrets built on the edge (so no space and water on the same map). Space ships are divided into space fighters, space corvettes, space battleships and space carriers, who can all fire at space targets, but only battleships and fighters can fire at ground buildings, and only fighters can enter the planet to shoot ground and air units (the battleship's Devastating Beam Of Death can shoot ground units but takes a while to recharge).
  • The Prophet gets an update as well: his Hurricane (mobile anti-ship spell) is replaced with a Meteor Storm that turns a fixed area of space into death to space ships.
  • The Pharos Lighthouse (grants visibility over a huge area of water) is replaced with the Space Station, which instead makes spaceships harder to kill.
• The Escape Velocity series of shareware games use most of these aspects. Spaceships are ships, bridges are either at the front or on top, 2-d space, sound, only a few days to the next system, etc. However, with the exception of a few "inertialess" ships there is no friction in space (unless, oddly enough, a ship is disabled), which makes combat turn out like jousting.
• Zig-zagged like crazy in EVE Online
  • Ship classes like Frigate, Cruiser, Battleship and so on all exist, and space has friction. Word of God says the programers cheated the space physics by using fluid dynamics formulas in the engine, and canonically, space in EVE has fluidic properties, which is why the game has missiles that use control surfaces to guide them as well.
  • On the other hand, a "torpedo" is simply a name for an immensely large, slow-moving missile, while the game also has rockets, missiles, and even cruise missiles. 3D space also plays a heavy role in travel and tactics, and space battles tend to have a more-or-less spherical front line rather than a two-dimensional one.
• Freelancer fits this trope to a tee. There is Space Friction: you lose speed if you kill your engines, and your ship returns to normal speed once you stop hitting the afterburners. Spacecraft are called ships, and although civilian spacecraft are called fighters, transports, or even space trains, capital ships are known as cruisers, frigates and gunboats. You wander around a 2-D Space, capital ships have a bridge with a big window more often than not, the Sci-Fi Writers Have No Sense of Scale and somehow managed to create entire planets only a few times bigger than a tiny little outpost, and on top of that, planets and stations are like fixed islands, completely devoid of rotation and translation. However, the game is well done enough to actually make this weird form of outer space rather believable.
• The FreeSpace space sim games refer to spaceships in nautical terms. The militaries that use these ships are called are called navies, and use navy ship classifications and personnel ranking. Fighters are akin to World War II atmospheric fighters — WorldWarII-style dogfights are actually mentioned on the box as a primary selling point. FreeSpace 2 even has a hidden pirate ship, the Volition Bravos, as an Easter Egg (it can be summoned using a cheat code). FreeSpace's terminology is an interesting example. It turns out that "destroyers" are battleship/aircraft-carrier hybrids and the largest warships in the game, while "cruisers" are the smallest, cheapest warships. The second game, set 32 years after the first, introduces "corvettes" which are in-between destroyers and cruisers in size, and a single frigate, which was corvette-sized but explicitly atypical and therefore didn't indicate what frigates are supposed to be by then^note the description puts that specific frigate as a one-of-a-kind pocket destroyer — the firepower and armor rating of a destroyer, the size of a corvette, and greater speed than either. Fighter units are formed into "squads," with "wings" being tactical elements of up to four fighters. Since this occurs centuries in the future however, it's likely all these changes were intentional, especially since Volition hired an ex-Marine NCO as a military consultant.
• The PC game Gratuitous Space Battles uses 2D space, friction in space and space fighters, Damaged ships even catch fire. Some mods have gone full circle, using the game to portray WW2 naval battles.
• Halo both uses and subverts this:
  • The UNSC ships are fairly boxy, but still has the bridge on the outer portion with a big window. The Covenant ships however, have their bridges close to the centre of their fairly streamlined designs. The series does, however, avert 2-D Space; see that entry for details.
  • The books hint that the UNSC Navy was consciously modeled after oceanic naval traditions, with some characters even lampshading the foolishness of human bridge placement; The Cole Protocol has a raiding Covenant Elite speculate upon seeing one that humans have far more reckless courage than most other races of the galaxy.
• Inca features a Tumi-shaped Inca ship fighting Spanish galleons, in space.
• The DS title Infinite Space refers to space as the "Sea of Stars" and ships generally follow the principles outlined in the intro. However, they do adopt wall formations instead of lines.
• Kaptain Brawe A Brawe New World is, essentially, Monkey Island Recycled IN SPACE!. According to the intro, humanity managed to make it into space in 19th century. So you have wooden spaceships with ion engines. Basically, the game takes every early sci-fi trope and runs with it. Planets are treated as no more than islands in Monkey Island. For example, an entire planet can consist of a bankrupt hotel and the immediately surrounding area. Union Space Police precinct 13 is a wooden Space Station that looks like a giant barrel with a funnel. Naturally, there are Space Pirates, although they later go under new management and become an evil corporation instead.
• Kid Icarus: Uprising takes this trope literally, as space is an actual ocean called the Galactic Sea where all the constellations are held in place. It's home to, among other things, Space Pirates who sail in a literal spaceship, green Space Whales and a monstrous astral kraken.
• The various worlds in Kingdom Hearts can be reached by travelling on the ocean, if Sora and Riku getting a Message in a Bottle from another world at the end of Kingdom Hearts II is any indication.The first game features Monstro flying through space along with Captain Hook's ship. It also features Sora, Riku, and Kairi planning on visiting other worlds by taking a raft out to sea, with Kingdom Hearts 3D [Dream Drop Distance] implying that, had their world not been destroyed, they might've succeeded.
• The Bioware RPG Mass Effect has this in spades, with nearly all of the terminology used by the Normandy crew (skipper, aye aye, aweigh, ashore...), the fact that the force it serves is the Alliance Navy, and the fact that a few other species' ships are given naval names as well (ex: the Quarian Flotilla). There are no particularly questionable uses of this trope, however.
  • The final mission of Mass Effect 2 shows the Normandy maneuvering through a debris field in a manner more suited to a stunt airplane than a ship. It seems that Mass Effect uses this trope for organizational and naming matters, but actual operations are a little better researched.
    Jeff 'Joker' Moreau: It takes skill to make a ship bank in a vacuum. Don't think it doesn't.
• In Pokémon, the Legendary Pokemon of Space, Palkia, is part Water-Type.
• The videogame Rogue Galaxy took this to the extreme end. All of the space ships are literal wooden ships, complete with masts, anchors and the like — except with rocket engines and forcefields built into them. They also have various interstellar lifeforms that look just like sea creatures.
• Star Fox: Sector Y is filled with wildlife that wouldn't be out of place in an ocean. Creatures that resemble jellyfish, manta rays, and even a whale can be found.
• The PC game Star General plays World War II IN SPACE for all it's worth, hardly surprising considering that the same developers brought us Panzer General and its successors. Not only do all the ships correspond almost exactly with their World War II namesakes, some of the factions seem to be Fantasy Counterpart Cultures for various combatants from World War II, including incredibly obvious Space Nazis.
• The Star Ocean series uses this in the title. The space portions are also clearly based on Star Trek. The first game even starts with a snippit of spoken dialogue taken directly from Star Trek — in English no less!
• The Star Control games can't quite decide what to do with this trope. Inertia and gravity wells play a big part in combat tactics, but combat takes place in 2-D plane. Also, most ships are equipped with forward-firing weapons which make combat much like an Old-School Dogfight, but a few ships have side- or turret-mounted weapons that are great for broadside attacks. Finally, despite operating in a frictionless environment, different ship types have different top speeds (which can be exceeded with a gravity slingshot maneuver). Star Control 2 takes this even further when traveling through its different dimensions. In normal space, the flagship uses very little fuel and generally relies more on inertia than continuous propulsion. Its top speed is still proportional to the number of thrusters, though. Hyperspace, on the other hand, is much more oceanic; the ship must continually expend fuel to move. Quasispace is an odd mash-up of the two which still has friction but somehow doesn't require fuel for propulsion.
• In the game Super Mario Galaxy, Bowser actually travels through outer space aboard what appears to be a flying sailing ship (which first appeared in the game Super Mario Bros. 3).
• Sword of the Stars uses the navy based naming conventions for ships, among some other standard features of this trope. In addition, the Whale people Liir take these descriptions further, describing their soldiers and explorers as "black swimmers", among other analogies.
• An option in the PC game Terminus, depending on the player's choice of "realism". The game features an actual sliding scale by which to set how realistically the ships move in space. If set to "Newtonian", there is no friction and thus constant motion does not require constant acceleration. Stopping requires using reverse thrust, and a ship's mass affects how well this works (trying to stop a cargo hauler full of ore will take minute at least). You can even overaccelerate and tear your ship apart, though they do give a max safe velocity. 2-D Space still applies, though.
• Traveller Also has this heavily for the terran, er, imperial side. Naval style commands were for military ship crews, traders require ship's papers (an amusing bit of fluff has a crew wondering why it's called papers if it's all on computers), Captain and all the attendant ranks as well. Smaller ships would be called boats, and have gigs to pick up crew from larger ships.
• Treasure Planet: Battle at Procyon, just like the film it is a sequel to, is a literal example of this as space in this game contains: islands, currents, whales, fish, pirates and submarines capable of hiding under the 'surface'.
• Virgin Victory, CENTINELS spaceship from The Wonderful 101 has sails on her. They don't do anything.
• X: This is mostly ignored in the series apart from Space Friction and Space Clouds, but there is the odd quirk that the majority of capital ships have their anticapital guns on the forward and flank batteries, with the flak guns above, below, and astern. Certain forum members also have a tendency to use nautical terms like port and starboard. Also avoided in that the Terrans use army ranks for their space forces instead of navy. Kyle Brennan, the Player Character of X: Beyond the Frontier, holds the rank of Major, while X3: Terran Conflict's Terran plot has you working under the overall command of General Ishiyama.
• Yooka-Laylee: Inverted in the Galleon Galaxy level. It's a Gangplank Galleon-themed level, set on a body of water, dotted with islands that have a lot of space-themed elements, including characters who dress and act like they're in a Raygun Gothic Space Opera. For example, you can transform into a galleon, but it's called a spaceship. Islands that are a short swim away are treated as separate planets.

Webcomics

• The trope is referenced in this Irregular Webcomic! strip, with the obligatory link to this page, where the NASA worker assures the (soon to be literally) Ascended Fanboy that that's not how space works.
• Pockett is built on this trope, complete with a sea-captain type space captain, tradional pirate syntax, and common navy crew protocol.
• Used to great effect in Second Empire, in which a second-hand Dalek warship designed for slow bombing runs utterly curb stomps a fleet of attacking fighters and a much more heavily armed enemy cruiser merely by having the captain realize the immense possibilities the aversion of this trope affords.
• The Sluggy Freelance takes this trope to extremes, with spaceships that have big honking sails on them. While solar sails are in fact a reasonably scientific idea, they probably wouldn't be slung on masts of craft which were basically spacefaring galleons, leaning instead towards thin sheets, many hundreds of kilometers across, designed to catch particles of the solar wind reflect photons. The characters are not in outer space in those ships, but rather in a kind of backwards universe where normal physics do not apply uniformly. It's referred to as "Timeless Space", and there is not only gravity and an atmosphere but also an ocean beneath them — but touching that ocean will cost a character all of their time and effectively kill them. They think, at least.

Web Original

• Mentioned by name in #2 of Cracked's 6 Sci-Fi Movie Conventions (That Need to Die).
• The Endless Night is a podcast about Space Pirates, which is chock-full of nautical comparisons — from borrowing the names of famous sailors for main characters (such as Nemo, Odisseus, and Ishmael) to the titles of the episodes.
• In Nexus Gate space is treated very much like an ocean. Why there are even space pirates who patrol the stars!

Western Animation

• Parodied on Back at the Barnyard. Otis and Pip are in outer space, with no idea of how to pilot the space shuttle they are in. Pip makes a remark about how, "that ship has sailed." Otis acts as if this reference to ships gave him an idea, saying, "Wait a minute? Ship? Sailing?" But then he admits, "No, never mind, I've got nothing."
• Futurama:
  • One episode focuses on a space cruise on a space ship called the Titanic. Fry wonders at one point if they hit a space dolphin, while Zapp Brannigan (the captain of the Titanic) makes as many comparisons between space and the ocean as possible.
  Zapp Brannigan: Comets — the icebergs of the sky!
  • There's also an episode where the Planet Express Ship starts Space Whaleing.
  • Another episode describes a cluster of Space Clouds with its own lighthouse.
  • In-universe, the protesters in "The Birdbot of Ice-Crataz" try to stop a tanker from maneuvering by surrounding it in a horizontal ring. Of course, the Captain of the tanker simply drops down a few hundred feet (which would not be practical for an ocean-going vessel, but is trivial for a space-going vessel) and flies off. The protesters (including Leela, who is the Captain of her own ship) shame-facedly admit that they never thought of that.
• Star Wars Resistance: The Colossus is somewhat of an inversion... a starship refueling station on the surface of a literal ocean, on an ocean planet. By the end of Season 1, it is no longer on the ocean...

Real Life

• This tradition has gone on so long that assuming Earth does ever manage create routine space flight, it is almost certain that this trope will be Defictionalized.
• There are some fairly recent advances in space travel that look straight out of this trope. Same principle, but it'd probably look more like a parachute. Given that even a normal sail is as much a wing as it is a sail, not only Space Is Air, but Ocean Is Air ar well.
• It is a possibility that the Navy might take over space faring expeditions because they already function on a tradition of being out at sea for long stretches of time living off of the resources on the ship, whereas the Air Force eventually has to get their air crafts back on the ground to refuel. Though in the event of any such Space version of the regular Military Forces there might be room for Joint Military Task Forces or even have the Air Force adopt Naval Traditions to avoid having authority stripped from them in Outer Space.
  • The recently-created US Space Force is a split-off from the Air Force. While they are still figuring things out, they are going to be under the Department of Air Force (just how the Marines are under the Department of Navy) and using Air Force ranks. However, the Space Force doesn't operate manned space vessels yet, so who knows what might change in the future.
• On the Apollo 12 mission (2nd lunar landing), the mission insignia featured a clipper ship, and the service module was named Yankee Clipper. The Lunar Module was named Intrepid, multiple US Navy ships have also had this name over the years. This was to highlight the naval service of the three crewmen.
• Astronaut and U.S. Air Force officer David Scott named the Apollo 15 Command Module Endeavour after Captain James Cook's ship. He felt that the Apollo 15 voyage was similar to Cook's in that they were both travelling to unexplored areas to discover new things. All other U.S. moon landings were commanded by naval officers or former naval officers.
  • The Space Shuttle orbiters — Columbia, Challenger, Discovery, Atlantis, and Endeavour, plus the prototype Enterprise — were all named after ships as well. Technically, the Enterprise was named after the spacecraft from Star Trek(thanks to a massive letter-writing campaign by millions of Trekkies), but it does share its name with several American warships.
• The Apollo astronauts used celestial navigation during their missions, something that sailors have been doing for centuries.
  • Early ballistic missile systems like Snark and Trident also used automated celestial navigation (using cameras fixed on particular stars) to improve their accuracy in the days before GPS and other more modern forms of guidance.
• In English, the very word "astronaut" is itself a Defictionalized example; it ends in "naut". As in "nautical". "Astronaut" quite literally means "star sailor!"
  • The same goes for the Soviet and Russian term "cosmonaut" (except that it means, well, "cosmos sailor").
  • The more rarely used Chinese equivalent "Taikonaut" also contains the "naut" syllable
• Much of modern space travel is derived from aviation, and much of that is derived from nautical tradition, partially because many of the early aircraft were seaplanes (because there were no runways yet). Many of the job titles associated with flying (Pilot, Stewardess, Purser, The Captain) and much of the other terminology was drawn from direct analogs in the seafaring trade (for instance, the fact that airplanes operate out of airports). Naturally, this all extended to space travel wherever applicable.
• The left and right side of a spacecraft are referred to as "port" and "starboard" respectively, such as during the launch of NASA's Orion spacecraft on 5 December 2014. This is actually carried over from airplanes, which also use these words.
• Since spacecraft aren't usually mass-produced the way aircraft or land vehicles are, a set of spacecraft built to the same specification is sometimes referred to as a "class", much like with ships. For example, two series of US Air Force spy satellites were code-named the Gambit-class and the Hexagon-class.
• NASA commissioned the artist Mark Rademaker to create a "realistic" depiction of what a faster-than-light starship might actually look like. Mark worked with Dr. Harold White, Advanced Propulsion Team Lead for the NASA Engineering Directorate, and the ship came out looking pretty realistic all things considered, but it still had a great big bridge perched on the front with windows and a deck oriented parallel to the ship's axis of thrust.
• When preparing the public communications just in case the Apollo 11 landing failed (often referred to as the "greatest speech never given"), the last prepared section was for a clergyman to perform the rite for Burial at Sea, with "commend their bodies to the deep" changed to "...the utmost deep."
• One of NASA's future Large Strategic Science Missions (top-tier, formerly Flagship missions) will be the "Europa Clipper". Justified as said probe's main target will be Jupiter's moon Europa, thought to harbor an ocean under a thick crust of ice.
• The Outer Space Treaty makes space to be treated essentially as international waters.

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