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Behold The Monolith!

Something huge has been spotted on the edge of uncharted space. It's miles long with a maw that could swallow a dozen star ships. It could hold a crew of tens of thousands or a crew of thousands ten miles tall. It's on a direct course for our solar system and we need you to investigate it.

Such is the Big Dumb Object. It's really, really big and really, really powerful. It could be a weapon or a habitat. The Big Dumb Object is always technologically more incredible than anything the discoverers have ever seen before, but, if it's dangerous, it probably has a silly weakness like logic, antimatter, or a well placed torpedo in the right air shaft. Sometimes it's disguised as a natural phenomenon. See also That's No Moon.

Its makers may be alive in a far-off, remote region. They may have Ascended to A Higher Plane of Existence, and this object is nothing more than leftover dust in comparison to their new existence. They may have gone extinct, and this object may be the last artifact of their society. The object may be some device or even an organ used by Eldritch Abominations to devour other worlds; it's possible that the object is an Eldritch Abomination. In any case, if they were so powerful and now they're all dead, what chance do we have?

Since Big Dumb Objects are so old and filled with advanced technology they are often the target of a race by several parties to unlock their secrets. In this case many Big Dumb Objects double as a MacGuffin.

The term "Big Dumb Object" for these things was coined by author Roz Kaveney.

Compare That's No Moon, Standard Sci-Fi Fleet, Dyson Sphere.

Examples of Big Dumb Object include:

Anime and Manga

  • The Bell in Magic Users Club, a giant alien something, invades earth and floats off the coast of Japan with it's own weather pattern.
  • Outlaw Star's Galactic Leyline is a massive library left behind by an ancient and now dead race. Several different factions spend the entire series theorizing about it and looking for it, and the titular Cool Spaceship and accompanying Spaceship Girl were created for the purpose of finding it.

Comic Books

  • Galactus of Marvel Comics fame is arguably a Big Dumb Object. Or, possibly a Big Smart Object. He just sort of wades through the galaxy eating things and creating general terror.
    • His ship, Taa II, fits the bill being the size of our solar system and so complex that Reed Richards is unable to even guess at most of its functions.
  • The first New Mutants annual featured an abandoned spacecraft the size of the inner solar system. It was also programmed to self-destruct. In a This Looks Like a Job For Aquaman moment, the only hope of averting the self-destruction was Cypher, a kid whose mutant power consisted entirely of the ability to learn new languages quickly.


  • The Star Trek movies have a few Big Dumb Objects for the Enterprise crew to contend with:
    • Star Trek the Motion Picture has a cloud-covered super ship called V'Ger (or Vejur). It was built around an old Earth probe named Voyager (no, not that Voyager, but rather a fictional 6th iteration in the real-life Voyager program) and sent back to meet its creator.
    • Star Trek IV the Voyage Home has a "Whale Probe" that disables every ship in its path by just looking at communicating with them and begins vaporizing Earth's oceans in search of an extinct species.
  • 2001: A Space Odyssey pits a single human up against a giant monolith in orbit around Jupiter. The Monolith serves as an alien teleportation device.
    • Well, you can argue that it also serves as a gigantic computer, an accelerator of human evolution and more or less (at least in the end sequence of the movie) as a total Mindscrew machine.
      • The monolith is best described as a "cosmic Swiss Army knife." It's capable of doing essentially anything required of it.
      • And there are more than just one...
      • ... and each is capable of self-replication...
      • 2010 ends with a whole fleet of them turning Jupiter into a second sun to kickstart evolution on Europa.
  • The Event Horizon from the film of the same name is a large ship stranded in a planet's upper atmosphere containing horrors and secrets.


  • The Jokers in The Dark Side of the Sun and the predecessor species from Strata (both by Terry Pratchett) had a hobby of building Big Dumb Objects. The Jokers built probably the biggest, dumbest object of all, which was a chain-link star system made with (as far as humans and other remaining species can tell) a complete disregard for the laws of physics.
  • Larry Niven's Ring World is probably science fiction's most famous Big Dumb Object. It is a habitable ring the size of Earth's orbit circling a sunlike star. The original builders were decimated and forced to live in primitive tribes scattered across the ring's inner surface.
    • Rainbow Mars, by the same author, features a tree large enough to conceivably be used as a space elevator. Turns out to be a very, very bad thing to have on your planet though, as it literally requires the entire planet's water supply to survive.
  • The titular object in Arthur C. Clarke's Rendezvous With Rama is an alien ship fifty kilometers long which comes zipping into the Sol System. It is seemingly abandoned but eventually slingshots around the Sun and disappears back into space, basically using the sun as a refueling stop.
    • In the sequels it's revealed that the Rama spacecraft is part of a vast intergalactic network tasked with collecting samples of intelligent life, which was made (essentially) by God. Nobody likes the sequels though...
  • Stephen Baxter's Xeelee Sequence novels feature an object called "Bolder's Ring" (or just, "The Ring") built by the titular aliens; it's constructed out of the remains of galaxies. It's a cosmic string - essentially a black hole that has been stretched into a one-dimensional loop millions of light years in length. In the series it is explained to be the cause of the Real Life "Great Attactor". At it's center? The sheer torque on spacetime from the gravity of the Ring tears a hole in the fabric of the universe, creating a portal to alernate universes.
    • Also, the "Sugar Lump" from the same series - a perfect cube the size (and mass) of a small moon. One character walking across one notes the strange gravity field: as you walk toward one of the corners, the flat "ground" under you increasingly seems to tilt until it seems like you're walking up a 45 degree incline. Once you reach the edge the gravity makes it feel like you're on top of a moutain sloping down on all sides.
  • Lots of these in Iain M Banks' Culture series.
    • The Excession from the novel of the same name is probably the purest example of this trope in Banks' work.
    • In Look To Windward we see Airspheres, planet-sized bubble-like artificial habitats with no internal gravity and filled with air (and bizarre airborne lifeforms) built by a long-vanished race for reasons unknown.
    • Much of Matter is set on a Shellworld, which is an artificial planet consisting of multiple hollow concentric spheres. Each internal sphere consists of a different discrete planetary habitat. We are told that there are thousands of Shellworlds and that they were built by a long-vanished race for possibly nefarious purposes. They also have a nasty habit of killing their inhabitants, though nobody has worked out what triggers them to do this. We also see a Nestworld, a vast Topopolis-like structure surrounding a star built by a contemporary neighbouring race of the Culture; we are told just this one Nestworld is home to 40 trillion beings, which is more than the entire Culture combined.
  • in Simon Ing's Hot Head a cluster of Von Neumann machines mining the Jupiter system go cancerous. The result is the Massive: it's growing exponentially and heading for the richer pickings of Earth. This is a classic Dumb Object: a gigantic mouth on the move. Ironically it's also anything but dumb: behind the mouth is a lump of computing substrate the size of a small moon. It's got so much virtual reality real-estate that the real world it is gobbling up is simply being overlooked.
  • The Dragon Rises by Adrienne Martine-Barnes mentions Precursors who'd become known as "Gamesters" because among their artifacts was a scattering, on many worlds, of huge cubes, purpose and makeup unknown, which resembled dice right down to having dots marked on the sides. The Gamesters also built warships some of which, despite being millennia old, were still capable of wiping out substantial battle fleets all by their lonesome.
  • The titular cube in Risto Isomäki's Xanadu-kuutio ("The Xanadu Cube") is a strange hollow cubical device that is Bigger on the Inside - so big, in fact, that its internal volume is apparently several times that of the rest of the universe.
  • Most artefacts and monuments left behind by already extinct alien civilizations in Alastair Reynolds' works (particularly the Revelation Space series).
  • The sphere in Sphere. Most of the book is spent figuring out what is does. It makes things you imagine real.
  • Robert Reed's Great Ship universe has the... Great Ship. It is a ship the size of Jupiter, made of the highest grade hyperfiber. Discovered streaking towards the Milky Way at a third the speed of light by a human built probe, its origin is unknown (the area behind it is the emptiest part of the universe), it carries an entire world inside it, and it has tens of millions of caverns and fusion reactors all there to make the interior livable for almost any species. It may be as old as the universe, and one character suggested that it created the universe, or functions as a control center for it - the visible universe simply being another layer to the ship's hull.

Live Action TV

  • Various Star Trek series featured Big Dumb Objects:
    • The Original Series:
      • The Doomsday Machine can chop planets into rubble with an anti-proton beam and use the chunks as fuel. Its hull material is derived from neutron stars somehow.
      • The Fesarius is a sphere ship a mile in diameter that contains a crew of only one and is used primarily as a bluff.
      • The generational ship Yonada is disguised as a giant asteroid. Its crew doesn't know they are on a ship and would not be told until they disembark on their destination planet.
    • The Next Generation:
      • Scotty is found by the Enterprise D marooned on the surface of an abandoned Dyson Sphere that is still programmed to draw ships into its docking bay with a powerful tractor beam. The Dyson Sphere is abandoned because conditions inside have become very dangerous.
      • Tin Man is a sentient biological ship that's been stranded for thousands of years without a crew. Both the Federation and Romulans want access to it, but only a powerful telepath can operate it. It is attempting suicide by supernova due to loneliness, having not had a crew in forever. A rather terrifying sort of existence, if you think about it.
      • The original Borg Cube is a semi-mindless killing machine looking for technology to assimilate with itself.
    • Voyager:
      • The Caretaker's Array is a giant space station whose technology is all but forgotten by those that made it. It can power a planet and transport ships from tens of thousands of lightyears away.
    • Enterprise:
      • Delphic Expanse spheres were moon-sized devices that could create spatial anomalies when networked together.
  • Blake's 7 featured not one, not two, but three Artificial Planets: Crandor, home of the Thaarn; Ultraworld; and Terminal (first called an "artificial planet," later called an "artificially modified planet").

Tabletop RPG

Video Games

  • The HUB in the X-Universe. A hollow sphere 60 kilometers in diameter, orbiting a red giant and extracting power directly from the sun's core, capable of modifying the Portal Network that links all the solar systems together. The builders are (likely) the same race who built said Portal Network.
    • In a rare example of a human built Big Dumb Object, there's the Terran's Torus Aeternal, which is a massive battle station that wraps along Earth's equator, which houses millions of people, produces part of the Terran's massive fleet, and has weapons large enough to blast anything and everything that gets close enough.
  • The Halo rings in Halo are superweapons capable of destroying all sentient life in the galaxy; they were built to stop The Virus (Flood) from spreading.
    • Halo 3 introduces "The Ark", an even bigger even dumber object that can build Halo rings inside of itself very rapidly by a completely automated process and then supposedly teleport them directly wherever they're supposed to go. It's also built outside of the Milky Way so that people could hide out there while the Halos kill all life in the galaxy.
  • Infocom's Interactive Fiction game Starcross is about the player discovering and exploring one of these.
  • Mass Effect has the Mass Relays, giant space constructs believed to be left behind by the Precursors. While they are the definite means of interstellar travel for the humans and other races, they are also part of the Abusive Precursors' omnicidal plans. The Citadel station applies as well.
  • The Star Trek the Next Generation game A Final Unity has the titular Unity Device, which has all the earmarks of one of these. It's actually a Dyson Sphere created by the Chodak to hold their vast galactic empire together by manipulating the very fabric of reality; it has the power not only to destroy an entire fleet, but to eliminate or create an entire species. A group of Chodak rebels, worried about the damage being done to reality, gained control of it and disappeared along with the device itself. When the rebels bonded with it, it ceased to be a Big Dumb Object and became a living one. At the game's best ending, Picard chooses not to wield its massive power to destroy the Borg, and it vanishes again to continue its peaceful mission of repairing rifts in the space-time continuum.
  • The entire Xenosaga trilogy's main plot is driven by the Zohar.
  • Shores of Hazeron has the Ringworlds, massive ringworlds left behind by unknown objects. These are fully colonizable and can have multiple cities.

Web Comics

Web Original

  • Orions Arm has a number of variations. Ranging from the more mundane Dyson Sphere and Banks Orbital, up to unique examples like the Leviathan which is 10 lightyears across, has a mass of over a billion suns, and is on a collision course with the Triangulum Galaxy.

Western Animation

  • In Transformers, Cybertron could be considered a Big Dumb Object, as it is artificial and no one knows who made it or its inhabitants.
  • The Star Trek the Animated Series episode "Beyond the Farthest Start" featured an alien podship a mile long and 300 million years old whose pods were exploded from the inside. The ship's insectoid crew left behind only a message warning of an invasive being that forced them to self-destruct rather than bringing it to their homeworld, which the mains take down fairly easily.
    • The same ship (or a very similar one) is a level in the Star Trek: 25th Anniversary point-and-click adventure game. Instead of the invader it is occupied only by the trader called Mudd, who has legally established salvage rights. The cause of its destruction is not discovered, but there are plenty of pirates in the area.
  • Superman: The Animated Series featured a tremendously old alien colossus that landed on Earth and was fed by heat. Its original purpose was as a construction tool.

Real Life

  • There's a hexagon on Saturn.
  • Dyson Spheres, if any of them are real.
    • They probably aren't, given that constructing one of reasonable thickness around the Sun at the Earth's radius of orbit would probably take more matter than is in the entire solar system, including most of the Oort cloud.
      • Assuming the Oort cloud isnt a Dyson cloud.
        • It isn't. Dyson clouds by nature intercept the light from the enclosed star. If that were the case, we wouldn't be able to see the stars.
    • By constructing nested Matryoshka Dyson spheres, each one would capture the energy emitted by the one closer to the sun, making an almost perfect system for capturing all the energy of the sun and with the outermost having roughly the same energy as the background radiation of the universe, making the whole system virtually invisible to observers...
  • There is a 600 light-years wide frozen ribbon spinning around the center of our galaxy.
  • On Earth, we have many examples stemming from the architectural achievements of ancient civilizations. These objects and the mysteries that have surrounded them might have been the original inspiration for all the other examples of this trope.