[[quoteright:301:https://static.tvtropes.org/pmwiki/pub/images/8855321_1002.jpg]]

->''"There are two sides in this, but they aren't inner planets and outer ones. Belters and everyone else. It's not like that. It's the people who want more violence and the ones who want less. And no matter what other variable you sample out of, you'll find some of both."''
-->-- '''Naomi Nagata''', ''Nemesis Games''

''The Expanse'' is a series of SpaceOpera novels by "James S. A. Corey", the pen-name of authors Daniel Abraham (''Literature/TheLongPriceQuartet'') and Ty Franck. Set a few hundred years in the future, humanity has expanded into and colonized large parts of the Solar System.

As of the beginning of the series, the three main political powers are Earth, Mars, and a rough coalition of "Belters" who inhabit the asteroid belt and many of the outer moons. These groups have been in economic dependence and conflict for almost as long as they've existed, but now shadowy conspiracies are pushing humanity to the brink of outright interplanetary war. As if that wasn't bad enough, in the midst of all this a virus-like alien "protomolecule" with [[BodyHorror horrifying capabilities]] has been unleashed and threatens the existence of all mankind.

Against this backdrop, the series mostly focuses on SpaceTrucker James Holden and his crew as they try to navigate through the increasingly dire political/cultural/existential crises plaguing the solar system, all the while trying to make a quick buck. Each book features new protagonists and side-characters, with the one constant thread throughout the series being Holden and his crew.

The technology featured in the series is relatively realistic but not described in detail. An unexplained breakthrough in fusion and drive technology (the Epstein Drive) has made interplanetary travel possible but there isn't any FTL travel and thus no interstellar voyages have been attempted yet.

The series consists of the following novels:
* ''Literature/LeviathanWakes'' (2011)
* ''Literature/CalibansWar'' (2012)
* ''Literature/AbaddonsGate'' (2013)
* ''Literature/CibolaBurn'' (2014)
* ''Literature/NemesisGames'' (2015)
* ''Literature/BabylonsAshes'' (2016)
* ''Literature/PersepolisRising'' (2017)
* ''Literature/TiamatsWrath'' (2019)
* ''Literature/LeviathanFalls'' (2021)

The novellas ''The Butcher of Anderson Station'', ''Gods of Risk'', ''The Vital Abyss'', ''The Churn'', ''Strange Dogs'', ''Auberon'', and ''The Sins of Our Fathers'' also take place in the same universe and serve to tie the novels together. A short story, ''[[http://www.syfy.com/theexpanse/drive/ Drive]]'', is a prequel concerning Solomon Epstein and the discovery of the Epstein Drive. A compilation of the short stories called ''Memory's Legion'' was released in 2022.

A [[Series/TheExpanse TV series]], produced by Creator/{{Syfy}}, premiered on December 14, 2015. Syfy cancelled the series on May 2018 to [[{{Understatement}} much fan, media and celebrity backlash.]] During the 2018 [=ISDC=], Jeff Bezos ([[JustForFun/OneOfUs himself a fan of the books and show]]), announced that Creator/AmazonStudios has picked the series up for additional seasons.

The authors are currently at work on a new series with elements of ScienceFantasy called ''The Captive's War''. The first novel, ''The Mercy of Gods'' is set for release on August 6th, 2024.
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!!''The Expanse'' series contains examples of:
%% * ActionGirl: Naomi Nagata, Clarissa Mao, and especially Bobbie Draper.
* ADayInTheLimelight: Many of the novellas shift the focus to characters who don't get many, if any, POV chapters:
** "The Butcher of Anderson Station" is about Fred Johnson and Anderson Dawes, their backgrounds, and their motivations.
** "The Churn" is about Amos's backstory.
** "The Vital Abyss" depicts how Corázar went from being an idealistic medical student to a sociopathic doctor.
* AlienGeometries: Anything the protomolecule creates, naturally, which includes the Ring Station and the ruins on Ilus/New Terra.
* AllPlanetsAreEarthlike: Averted. While many of the colony worlds superficially resemble Earth's environments in certain ways it's repeatedly stressed that humans are unable to safely eat the native flora and fauna and that many colonies are reliant on imported food and soil for their survival. Auberon, mentioned as one of the few that can easily support Earth crops without any intensive effort, quickly becomes one of the most populous and wealthy worlds after the time skip.
* AmbiguousRobots: The protomolecule civilization left behind mechanical drones that seem to be a little like insects and a little like robots. Any structure built by the protomolecule seems to look both artificial and organic at the same time, with any moving mechanical components bending and pulsing rather than spinning or clicking.
* AmbiguousEnding: "The Sins of Our Fathers" [[spoiler:ends without letting the reader know if Filip will survive his five-year exile or if the settlement itself will survive.]]
* AndIMustScream: The fate of anyone absorbed into the protomolecule, such as [[spoiler:everyone on Eros station. As of ''Cibola Burn'', it turns out they're still vaguely conscious in the protomolecule. The Miller apparition was largely exempt, as it was made by the protomolecule to investigate the gate shutdown]].
* AntiInterferenceLockUp: In ''Caliban's War'', Chrisjen Avasarala and Bobby Draper get invited to board an [[ConspicuousConsumption incredibly luxurious spaceship]] ''Guanshiyin'', together with its owner Jules-Pierre Mao, for a months-long humanitarian trip to disaster-struck Ganymede. Both suspect it's a GildedCage to keep them out of the political game [[spoiler:for finding out that Errinwright was keeping them in the dark on what Admiral Nguyen was doing around Jupiter]], and once they board the ship[[note]]They agree because refusing would completely ruin Avasarala's political power.[[/note]] their suspicions get proven right when their communications become monitored, Jules departs prematurely on his private yacht and the staff aboard the ship becomes evasive about giving access to emergency communication systems. Thankfully Bobbie was wise enough to smuggle-in her PoweredArmor.
* AnyoneCanDie:
** In ''Leviathan Wakes'', [[spoiler:all but five of the Canturbury's crew is killed,]] and when the survivors are rescued, [[spoiler:Shed dies.]] At the end [[spoiler:Miller, whom half the book focuses on, dies in a HeroicSacrifice]].
** In ''Abaddon's Gate'', there's [[spoiler:Bull and Sam.]]
** In ''Babylon's Ashes'', there's [[spoiler:Fred Johnson]], the only character besides the ''Roci'' crew to appear in every single book to date.
** In ''Persepolis Rising'', [[spoiler:Santiago Singh]] and [[spoiler:Clarissa Mao]] both end up dead.
** In ''Tiamat's Wrath'', [[spoiler:Avasarala dies of natural causes at the start of the book and Bobbie sacrifices herself to destroy the ''Heart of the Tempest''.]]
** In ''Leviathan Falls'', [[spoiler:Tanaka and Duarte suffer a MutualKill, and Holden sacrifices himself to shut the ring station down permanently. By the DistantFinale, everyone is dead except Amos]].
%% * AsteroidMiners: A lot of this goes on in the belt though it doesn't directly impact the plot much.
%% * ArcWords: "Doors and corners"
%% * AutoDoc: Military ships come equipped with automatic medical systems.
* AwesomeButImpractical: Artificial gland implants like Clarissa's are widely seen as this in-universe. They allow the user a few moments of heightened strength and reaction time, which would make them a formidable weapon... except that they're also expensive, with aftereffects that cause the user to crash and spend a several minutes vomiting after use. [[spoiler: They also degrade with age and start leaking into the bloodstream, causing terminal illness. And they can't be removed without killing the owner.]]
* TheBattlestar: Martian ''Donnager''-class battleships are Type 1. Half-kilometer long vessels with a crew of over two thousand, including companies of marines. They are heavily armored, equipped with torpedo tubes with generous magazines of both plasma and nuclear warheads, point defense networks with multiple overlapping fields of coverage, and a pair of [[MagneticWeapons high-yield Gauss emplacements]] for slugging it out with other capital ships in a close-range battle. Add to that its interior docking berths are large enough to hold a few Corvette-class frigates which can be deployed to screen its flanks, detach for scouting, or run down targets which might otherwise try to outrun the battleship.
* BeenThereShapedHistory: Holden and his crew continually get caught up in larger historical events, frequently influencing the outcome.
* BodyHorror: As the author puts it in the afterword to ''Leviathan Wakes'':
--> "I've never written anything in my life that didn’t at least blur the line into horror. If I wrote greeting cards, they'd probably have a {{squick}} factor."
%% ** Happens at least once a book, mostly thanks either directly or indirectly to the protomolecule.
* BookEnds: On the immediate level, the first and last book being called ''Leviathan Wakes'' and ''Leviathan Falls'', respectively. [[spoiler:''Leviathan Wakes'' explores humanity's first contact with alien technology whose consequences it barely understands, while ''Leviathan Falls'' brings its greater influence to a close as the ring space created by said technology is shut down by Holden to save mankind from extinction.]]
* CasualInterplanetaryTravel: Acquiring a small ship capable of interplanetary travel seems to be about as difficult as acquiring a house is now. With all the attendant risks of defaulting on your loans and having it seized by the bank. It still requires weeks to months to get anywhere though.
* ChekhovsGun: The ''Razorback'' is first mentioned in ''Leviathan Wakes'', only to play a critical role in ''Caliban's War'' and later again in ''Babylon's Ashes''.
** In ''Nemesis Games'', it's revealed that a large number of military and civilian ships have gone missing. [[spoiler:The military ships were stolen by Marco Inaros and become the major threat through ''Babylon's Ashes''. The civilian ships, however, just ''vanished'', and the mystery of what happens to them becomes very relevant later in the series]].
* CivilWarVersusArmageddon: The Earth-Mars Coalition breaks down into interplanetary war and the Belters openly rebel against both planets due to the machinations of a MegaCorp experimenting with -- and failing to control -- the alien Protomolecule that threatens to consume all life in the solar system.
%% * ColonyDrop:
%% ** Discussed a lot. Asteroid drops are the new Mutually Assured Destruction.
%% ** [[spoiler:Used against Earth with devastating effects in ''Nemesis Games''.]]
* ColonizedSolarSystem: Early on there were only Lunar settlements and a colony on Mars, with anything further out too difficult to make permanently habitable or even reachable via anything crewed. Once the Epstein Drive was invented though, spreading further out suddenly became a lot more economically viable, and the subsequent "gold rush" to claim land and resources resulted in a mostly colonized solar system by the beginning of the series.
* CommonPlaceRare: Actual cheese is worth, pound-for-pound, more than starship fuel. Ceres Security once parceled out the cheese they confiscated from a smuggling ring to its employees.
%% * CompanyTown: How Ceres and the rest of the Belter colonies are run, which is why the OPA is becoming popular.
* CoolStarship:
** Both present and averted. It is noted that the lack of atmosphere to deal with, combined with efficient designs, has resulted in mostly ugly, blocky looking ships. Some of them are very large and impressive, but still look like a simple warty skyscraper laid on its side. Some of the ships however, as exemplified by the ''Rocinante'', are very cool on the inside.
** The ultra-rich do have more idiosyncratic designs for their personal space yachts, as do some OPA captains with their flagships.
** The United Nations navy also includes stealth ships, which are described as being extremely sleek. This is both to minimize their radar profile and to minimize the total surface area that needs to be equipped with sensor absorption paneling. [[StealthInSpace The result is something that is hard to find and hard to get a weapon lock on.]]
* CorporateConspiracy:
** A lot of people die in ''Leviathan Wakes'' thanks to Protogen's plan to test out the Protomolecule by unleashing it on the entire population of Eros. Just their distraction plan of starting a war between Earth, Mars and the Belt kills thousands, and then there's the population of Eros.
** It continues in ''Caliban's War'' with Mao-Kwikowski (of which Protogen was a subsidiary). In this case they try to weaponize the Protomolecule by creating {{Super Soldier}}s, reigniting hostilities between Earth and Mars.
%% * CorruptCorporateExecutive: The Protogen executives and their backers, such as Dresden and Jules-Pierre Mao respectively.
* CrapsackWorld:
** Earth. The UN adopted a welfare state while also failing to provide sufficient educational programs for people who want to take on a trade. From the looks of it, the system drew a hard line between upper and lower classes. The welfare state doesn’t prevent homelessness, and Earth is falling behind Mars technologically, both because it's wasting its potential talent and because a generations-long BrainDrain is pulling the best and brightest to Mars.
** Any Belter settlement, and the Belt in general at the start of the series. Vital services are provided by ruthless corporations that put profit far ahead of people, justice is laughably rare, and the inner planets manipulate economic conditions so that it's impossible for Belters to get ahead. Life expectancy in the Belt is abysmal compared to Earth and Mars. About the only nice places are those micro-managed by megacorporations, like Tycho Station and Ganymede.
** Later in the series, Mars. After [[spoiler:the ring gates open up hundreds of planets for colonization, all of them more livable than Mars]], millions of Martians decide their world is a dead end and abandon it. Mars increasingly becomes a ghost planet, with both its government and its people realizing its time has passed.
* DawnOfAnEra: At the end of ''Abaddon's Gate'', [[spoiler:Holden shuts down the ring station's security protocol, which opens over a ''thousand'' gates to other worlds, many of which are habitable]]. The next few books deal with the consequences of this.
* DomedHometown:
** Martian cities are under domes because though the planet is being (slowly) {{terraform}}ed, it is nowhere near habitable yet.
** Transparent domes are ubiquitous on the surface of Ganymede, but rather than housing cities they house farmland, where the transparency is necessary for the crops to get sunlight (which is further strengthened by orbital mirror arrays.) The actual habitation there is underground, carved out of the moon's thick surface ice.
* TheDreadedDreadnought: Magnetar-class battleships, deployed by [[spoiler:Laconia]]. They're huge, bristling with cutting-edge weapons, capable of self-repair, strong enough to tank nuclear weaponry, and pack a WaveMotionGun that can obliterate a city-sized ship ''at the atomic level'' in a second.
* EarthIsTheCenterOfTheUniverse: Mars is in some ways more technologically advanced and both Mars and the Belt view themselves as independent of the home planet, but more educated people are pretty sure that they couldn't survive without access to the resources of Earth. The core issue is that the artificial ecosystems that support human life in space are incredibly fragile; they cannot be started or maintained without biological material shipped up from Earth.
* EldritchAbomination: [[spoiler:The PrecursorKillers listed below definitely qualify. Whatever they are, they seem to exist largely outside of dimensional space, and attack either by firing ''anti-consciousness'' weaponry or erasing spaceships out of existence entirely. Elvi Okoye is a witness to the latter in ''Tiamat's Wrath''.]]
* EldritchLocation: In ''Leviathan Falls'', [[spoiler:it's revealed that the ring station and the slow zone exist in a different universe, with different fundamental laws. It draws power from the conflict between the laws of our universe and the next, and the PrecursorKillers are ''not'' happy that it's being used again]].
%%* FantasticRacism: Earthers vs. Belters vs. Martians.
* FantasticSlurs: "Dusters" for Martians, "skinnies" for Belters and "Squats" for Earthers.
* FateWorseThanDeath: For the Earth elites, being threatened with a life on Basic Assistance is considered this. Of course, to Belters, a life of guaranteed food and shelter sounds like paradise (ignoring the unsafe living conditions, the high crime rates, the lack of social mobility, and other mitigating factors).
* FloodedFutureWorld: [[GlobalWarming Climate change]] has resulted in many coastal buildings getting lost in the water. While those in space are killing each other over water, Earth is practically drowning in it.
* FooledByTheSound: In the short story "Strange Dogs", as Cara runs off into the woods at night, she records a feigned cry for help on her tablet and drops it to fool her parents as she runs in another direction.
* FourTemperamentEnsemble: The Roci's crew.
** Holden: Melancholic.
** Naomi: Phlegmatic.
** Amos: Choleric.
** Alex: Sanguine.
* FutureFoodIsArtificial: Extremely common. Mars and the Belt have no natural arable land, and all their food production is necessarily done in capital-intensive artificial environments using crops which are heavily genetically modified to yield maximum nutrient return for the organic and energy resources invested in growing them, with various soybean and fungi derivatives particularly common staples. Even Earth, with its vast biosphere, depends on similar technological means to feed its enormous population. This does not stop demand for variety, and many of these staples are combined and treated to give approximations of other foodstuffs ("steak" made from compressed fungus stalks for example.) For those with a little more wealth to spend on consumables, vat-grown meat is also available. Genuine organic food and animal products such as cheese are luxury goods, especially the further out one goes from Earth.
* FutureSlang: Belter slang, which is a mix of various languages.
* GenerationShips: At the start of the series, the ''Nauvoo'', a generation ship commissioned by the Mormons, is nearing completion at Tycho Station. It's later stolen to use as a ram to throw Eros into the sun, retrofitted into a warship and renamed ''Behemoth'', then ends up as Medina Station, a waystation in the slow zone. Ultimately, [[spoiler:the dark gods destroy it]] in ''Tiamat's Wrath''.
* GenreThrowback: The authors describe the series as a renewal of old school SpaceOpera with both the science and the tropes updated for the 21st century.
* GoneHorriblyRight: Inventor of the Epstein Drive discovers, to his detriment, that it works far better than he dreamed. Protogen's experiments with the protomolecule and their attempts to distract Earth and Mars all work FAR better than they planned, to their detriment.
* GoneHorriblyWrong: The protomolecule was sent by precursors to terraform Earth when it had single-celled life, presumably to seed a colony of themselves. When it encounters multicellular life (ie, humans), it turns them into paste. [[AndIMustScream Still-alive, still consious, still screaming paste]]. That or {{Plague Zombie}}s.
* GreyGoo: Averted. While the Protomolecule can and will render people down for more biomass, it doesn't eat inanimate objects. It tends to work said biomass into the decor..
* HighSpeedMissileDodge: {{Play|ingWithATrope}}ed with. In space, no crewed ship can compete with an anti-ship missile for thrust-to-mass ratio and acceleration tolerances, so actual dodging is practically impossible. However, an AcePilot of smaller craft can still use their skills to jink and spin in ''just'' the right way to give their counter-measures a few critical fractions of a second more to down an incoming missile before it reaches critical distance from its target.
* HomosexualReproduction: Medical technology in this setting involving gene splicing and surrogacy is reliable and inexpensive enough that it is commonly employed by same-sex couples who want to have biological children together.
* ImpededCommunication: This is a major issue throughout the series, due to the simple physics of reality. Light cannot travel faster than ''c'', and therefore neither can radio transmissions. So, ''light-delay'' must be accounted for when sending messages across the infinite void of space.
* IronicName: Laconia is named after the region of Greece that Sparta is in, but the title of ''Persepolis Rising'' implicitly compares them to the Persian Empire.
* LawEnforcementInc: Private contractors have taken over most law enforcement functions, with varying results: while Star Helix ''attempts'' to be a legitimate police force on Ceres, other outfits like CPM [[spoiler: a subsidiary of Protogen consisting mostly of former inmates and gang members recruited as muscle]] are only just ''barely'' better than the criminals themselves. See also MegaCorp below.
* LegendaryInTheSequel: Holden becomes increasingly more famous after each installment, and although he doesn't necessarily ''like'' the attention it does feed his ego and occasionally [[NoHeroToHisValet the rest of the crew and his employers have to bring him back to reality]]. In later volumes the leadership of the UN and OPA use Holden's fame to their advantage, hiring the crew to mediate conflicts and [[spoiler: lead the combined UN/Mars/OPA task force seeking out the Belter Free Navy at the end of ''Nemesis Games'']] because of Holden's high profile, general trustworthiness, and heroic public image.
* {{Lightworlder}}:
** {{Downplayed|Trope}} by Martians, who find Earth-normal gravity uncomfortable and exhausting unless they go through a lot of muscle-therapy and training (as the Martian Congressional Republic Marine Corp habitually does.)
** Played much straighter by the Belters, who often grow up with only a minor rotational gravity or thrust gravity and spend a significant portion of their life in zero-g. This results in them having low-density bones, with tall, thin frames, and it's legally considered torture to force them into a high-gravity environment without sufficient physical support. Some of them are capable of overcoming this limitation with lots of training and hormone treatments, but not all of them can afford that nor can some of their bodies support it.
* MagneticPlotDevice: Holden effectively becomes one due to his many experiences with the protomolecule. For example, if any other diplomat had been sent to Ilus [[spoiler: they wouldn't have activated the planetary defense systems]]. Later, Holden gets special treatment [[spoiler:by the Laconians]] after triggering alarms on the Medina because [[spoiler: Holden was the only person to have interacted with the Ring Station and Duarte wanted information on it.]]
* MeatMoss: Anywhere the protomolecule has had time to take over ends up looking like something from ''VideoGame/DeadSpace''. It's especially gross because it's still got bones and organs floating in it.
* MegaCorp: Several of them exist, with as much or more power than the planetary governments. Some, like Protogen or Mao-Kwikowski, verge on NGOSuperpower [[spoiler: until they run afoul of the ''real'' powers of Earth and Mars, and get dismantled]]. Others, like RCE, are somewhat more ethical [[spoiler: although in RCE's case one [[{{Sociopath}} sociopathic security chief]] makes life difficult for everyone--the company included--in ''Cibola Burn'']]. The extent to which the corporations are in charge is so great that the setting's MirandaRights includes a provision for a union representative as well as (or in place of) a lawyer for a suspect upon arrest.
%% * MildlyMilitary: Holden and his crew, given that they are independent operators of a piece of (at the time they got it) top-of-the-line military hardware.
%% * {{Nanomachines}}: The Protomolecule is close to this, in function if nothing else, but it's structure is far too simple to be what we would recognize as a machine while still being far too complicated in what it can to do be organic.
* NoBiochemicalBarriers: [[spoiler:{{Averted|Trope}} by the habitual exo-solar planets on the other side of the [[{{Precursors}} Protomolecule Civilization]]'s ancient PortalNetwork. Physics being what they are, those planets are chemically similar to Earth and even have some similar evolutionary drivers resulting in Earth-analogous biospheres, but the biochemistry is incompatible. This limits the new colonies' growth and ability to survive independently since their food production can rarely be entirely self-supporting.]]
* NoPlansNoPrototypeNoBackup: Averted with the Epstein Drive, which was recovered from plans kept by its inventor - who decided to test the first prototype with himself on board[[note]]Once he turns the drive on, it immediately accelerates at what has been worked out to 11.5g, which would have knocked him out almost immediately, and killed him within minutes - even had he remained conscious, he would have been utterly incapable of moving so much as a finger, let alone enough to turn the drive off. He accelerates for 37 hours, and ends up at 5% of ''c''[[/note]].
--> "Solomon Epstein had built his little modified fusion drive, popped it on the back of his three-man yacht, and turned it on. With a good scope, you could still see his ship going at a marginal percentage of the speed of light, heading out into the big empty. The best, longest funeral in the history of mankind. Fortunately, he’d left the plans on his home computer."
* NuclearMutant: The Protomolecule seems to have the ability to metabolize radiation to fuel itself, not dissimilar from the way plants photosynthesize sunlight but at a far higher level of energy, and severe radiation rapidly accelerates its growth.
* NuclearOption: Every major faction (Earth, Mars and the OPA) has access to nuclear weapons - and are willing to fire them in anger. Since the ColonyDrop has become the new real weapon of mass destruction and nukes are mostly used for ship-to-ship combat, they're not as taboo as in real life.
* NuclearTorchRocket: the Epstein Drive, a kind of fusion rocket that can generate multiple G's of thrust. During which everyone sits on couches and takes drugs in order to survive the crushing force.
* ObsoleteOccupation: Most [[SpacePeople Belters]] make a living from [[AsteroidMiners mining asteroids]], and the Martian Congressional Republic likewise keeps people together largely through the prospect of [[{{Terraform}} turning Mars into a garden world]], so when a PortalNetwork shows up connecting the Solar System with over 1300 worlds --many of them hosting planets rich in resources ''and'' breathable atmosphere-- those two groups suddenly find themselves in quite a bind.
* OutgrownSuchSillySuperstitions: Completely averted. Humanity is just as religious as it has ever been, with all of today's religions and some new ones featuring in the story. The Mormon Church in particular appears to have become quite wealthy and powerful, to the point that it can fund its own interstellar expedition.
* OutsideContextProblem: The protomolecule, its creators, and the ones who destroyed them present a constant series of these. Just when everyone thinks they're starting to get a handle on how things work, a curve-ball gets thrown their way through some unexpected application or interaction with the technology that flips everything on its head. [[spoiler:The Laconians end up causing these in rapid succession by repeatedly provoking the entities within the gate system, first causing them to collapse a neutron star into a black hole and unleashing the mother of all {{Wave Motion Gun}}s, and later causing them to attack the slow zone directly and annihilating everything within.]]
* PocketRocketLauncher: Most weapons are recoilless (a typo in the first book labels them "reactionless") pistol-sized rocket launchers, usually mounted on the wrist of a suit of PoweredArmor; sometimes in a [[GatlingGood three-barreled minigun]] configuration.
* PoweredArmor: Used by {{Space Marine}}s in combat, though the Martian Congressional Republic Navy probably has the most cutting-edge variation, able to keep a marine fighting even after sustaining multiple hits from infantry-scale weaponry.
* {{Precursors}}: The creators of the protomolecule, who existed billions of years before humanity.
* PrecursorKillers: [[spoiler: The thing that forced the original precursor aliens to lock down Ring Station. As of ''Nemesis Games'' they may be back because ''something'' is eating ships that go through the Ring.]]
** [[spoiler: As of Tiamat's Wrath, they are definitely back. After the Laconians sent a bomb at them, they caused a neutron star to collapse into a black hole, wiped out every human ship and installation inside the Slow Zone and (if Elvi is correct) are ''trying to figure out how to switch off all human consciousness''.]]
* QualityVsQuantity: The Martian military is a big believer in quality over quantity. Bobbie realizes the weakness of that position on her first trip to Earth. Although Martian Marines train in Earth gravity, they'd face many additional challenges in a ground war--like the fact that one good-sized Earth city would be populous enough to overwhelm the entire MMC even if they were only armed with sticks.
%% * {{Rail Gun}}s: Part of the standard armament for military vessels.
* SciFiWritersHaveNoSenseOfScale: Thoroughly averted. The inherent bigness of outer space is constantly referenced in multi-week-long travel times and the lag of message transmissions which take between tens of minutes to several hours to get from place to place even when travelling at the speed of light. Specifically in ''Cibola Burn'', even with the contracted scale of orbiting a planet, the Roci has to zoom in its telescope to to 50X magnification just to have a thumbnail-sized view of another orbiting ship.
** The authors did not appear to be aware of how much water is in Ceres - it's estimated to be at least 25% water and have more water than Earth. Yet the inhabitants of Ceres need to import water (where is their water going? it should be a closed system and the only way water would be lost is it it was vented to space or broken down into hyrdroogen and oxygen)
-->Basia: '''“Space is too big,”'''
-->Alex: '''“It’s been said. And this is just the space in low orbit around one planet. Breaks the head a bit to think about.”'''
-->Basia: '''“I try not to.”'''
-->Alex: '''“Wise man.”'''
* SecurityBlindspot: In ''Tiamat's Wrath'', LaResistance discovers the [[TheEmpire Laconian]] dreadnought occupying the Solar System has a blind spot in its sensor array and promptly plans an attack on that dreadnought using an {{antimatter}} core that was meant to power it.
%% * TheSociopath: Amos Burton is basically one, but he tries to do right by [[TheConscience following the lead of an ethical person]].
%% * SonOfAWhore: Amos.
%% * SpaceBattle: Several.
* SpacePirates: Naturally. Mentioned a few times in the book but don't have much to do in the plot [[spoiler:until the Belter radicals start seizing Martian Ships in ''Nemesis Games'']].
* SpaceStation: Tycho Station. By ''Nemesis Games'' Medina Station [[spoiler: formerly the ''Nauvoo'']] is positioned at the Ring Station, a strategic meeting place that all ships attempting to use the Ring network must use, not unlike [[Series/Babylon5 a certain other space station]].
* StatusQuoIsGod:
** The crew of the ''Rocinante'' remains unchanged over five books -- it's just Holden, Naomi, Amos and Alex. In ''Nemesis Games'' Naomi mentions that their PlotArmor might not hold out forever and it would probably be a good idea to get some extra crew aboard just in case someone needs to take over someone's position in a crisis. Independently of Naomi, Alex also notes that even a minor personality conflict amongst any two members of the crew is likely to doom the whole operation, and that a larger crew would help change the interpersonal dynamics and avoid disaster. By the end of the book it seems as if [[spoiler:Bobbie Draper and Clarissa Mao]] might finally be permanent additions to the crew.
** Averted in ''Persepolis Rising''. [[spoiler:The book starts with Naomi and Holden deciding to finally retire and leave Bobbie as the new Captain of the ''Rocinante''. By the end of the book, Clarissa is dead, Holden is a prisoner deep behind enemy lines on Laconia, and Bobbie and Amos are now crewing the stolen Laconian frigate ''Gathering Storm'', leaving Naomi and Alex as the only crew left aboard the ''Rocinante''.]]
** Played with in ''Tiamat’s Wrath''. [[spoiler:While Naomi, Holden, Alex and Amos all end up back on the ''Roci'' by the end of the book, Bobbie is dead and Amos has been [[CameBackWrong resurrected as some kind of part-alien construct]].]]
* StealthInSpace:
** Earth and Mars both have stealth ships in the sense that they're designed to not radiate heat; using radar in space is impractical due to the distances involved, so most everyone looks for heat signatures instead. Which means that using your engines gives you away immediately (lots of heat) and people frequently talk about "lighting up" everything around them by doing so.
** ''Nemesis Games'' also mentions a special stealth coating that can be applied to ships which masks their radar signature. [[spoiler: The "Free Navy" uses it to hide the asteroids they send to hit Earth.]]
* SufficientlyAdvancedAlien: The protomolecule and the other technology from the aliens, once it gets to work, is able to do things utterly impossible by the standards of human technology. It's able to ignore inertia, lock down maximum speed within an area of effect, disassemble ships piece by piece instantly, [[SubspaceAnsible communicate at FTL speeds]], and eventually [[spoiler: form a wormhole to a hub of other wormholes]]. Several characters explicitly refer to the technology as God-like.
* {{Terraform}}: A project to terraform Mars is ongoing, but it is currently still reliant on imports from Earth. [[spoiler:The creators of the protomolecule apparently intended to use it to "alienform" the then primitive Earth.]]
%%* Soft Robot: The Protomolecule-makers' maintenance robots are partially organic with squishy bits. One destroyed robot leaves behind a liquid stain on the floor after its' fellows are done cannibalizing it for parts, similar to what's left of the Martian Marine that destroyed it. - Rogue launched trope
* ThemeNaming: Many of the Laconian warships, particularly their ''Storm''-class destroyers, are named after meteorological phenomena (''Gathering Storm'', ''Monsoon'', ''Mammatus'', ''Rising Shamal'', etc.).
* ThrownOutTheAirlock: Happens at least twice and is mentioned numerous times as appropriate punishment for especially unpleasant people. Among the Belters, throwing someone out the airlock is [[MakeAnExampleOfThem a method of execution to make a statement]], "This person endangered the environment we all live in." Belters take the maintenance of their artificial environments ''very'' seriously and violators are considered especially heinous.
* TrademarkFavoriteFood: Bull, a New Mexican, goes to the trouble and expense of having frozen Hatch green chiles shipped all the way out to the Belt. The authors, being from Albuquerque, know that this is TruthInTelevision -- wherever New Mexicans go, they will take Hatch chile with them.
* UnitedNationsIsASuperPower: The UN literally controls Earth and its armed forces.
* UsedFuture: Many of the civilian spacecraft are described in such a way that you just know some crucial life-support system is being [[DuctTapeForEverything held together by duct tape]].
%% * TheVirus: The protomolecule.
* TheWarOfEarthlyAggression: This is one of the things that the Belters are worried about, although they're more immediately worried about a War Of Martian Aggression. Mars itself has also prepared for war with Earth, both in terms of military buildup and running elaborate battle simulations. [[spoiler:In ''Nemesis Games'', the Belters launch a devastating first strike against Earth, with the assistance of a Martian splinter group.]] Subverted, at least with respect to Mars, in that Mars has the upper hand--Earth may have more ships, but Mars has better ships, and its crews are better-trained than Earth's. Holden mentions that in every simulation the UN ran of an Earth-Mars war, Mars wins rather lopsidedly, unless Earth launches a devastating first strike.
* WeWillWearArmorInTheFuture: Ballistic suits with rigid plating are common among all the militaries and sufficiently-funded private security. While military-grade weapons often pack [[ArmorPiercingAttack armor piercing rounds]] sufficient to penetrate it, it does still provide reasonable protection against civilian-grade small arms or plastic low-penetration rounds commonly employed when depressurization is a serious hazard, such as on a space ship or space station. If that is not enough, many of the militaries also employ PoweredArmor for when they really need an infantry-equipped force-multiplier, but such suits are expensive and take half a year of training to be fully qualified to operate, so their use tends to be limited to elite forces.
* WhatHappenedToTheMouse: At the end of ''Babylon’s Ashes'', [[spoiler: Filip abandons the Free Navy, gets a labourer job on Callisto and changes his surname to “Nagata”]]. He never shows up again, only getting a brief mention in ''Leviathan Falls'', [[spoiler:which reveals that Naomi still thinks he died with Marco]].
** While his daughter plays a significant role in ''Tiamat's Wrath'' and ''Leviathan Falls'', Payne Houston barely gets a mention after the ''Roci'' turns him over to the Transport Union.
* WhatMeasureIsANonHuman: In universe example - Belters, and Martians to a certain extent, who grew up under low or micro-gravity are tall and skinny and look slightly deformed to people who grew up on Earth. Belters also have their own dialect that can make it difficult for "Inners" (Earthers and Martians) to understand what they're saying even when theoretically speaking the same language. It is speculated that many Inners don't even view Belters as real humans anymore and that is part of the reason why conflict has developed between them.
* WorfEffect: The Martian Congressional Republic Navy is constantly referenced as being the best there is. They get their asses kicked ([[CurbStompBattle curb-stomped]], really) an awful lot.
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