And by “they,” I mean the aliens. Obviously.
Feats of engineering and buildings on a grand scale have long captured the minds and imaginations of futurists. The Eiffel Tower, originally planned to be a somewhat temporary structure for the 1889 World’s Faire, a marvel of being the first man-made structure to surpass both 200 and 300 meters, evoked awe and wonder in attendees and tourists long thereafter as both a symbol of France’s past hundred years as a republic and as a monument to greatness yet to come. The tower held the prestigious record of tallest structure in the world for four decades, before being unseated by the Chrysler Building in the ‘30s. “I ought to be jealous of the Tower,” Gustav Eiffel once bemoaned, “she is far more famous than I.” Quickly, those whose imaginations drifted forward towards the question of “what if” asked: If our mastery of science and technology had given us this power, what more could we build? How much higher will we go?
But what makes a structure a megastructure? To be blunt and pedantic, it is any structure that is, well, mega. We’ve been building megastructures for millennia; the Great Wall of China fits the bill, coming in at nearly 4000 miles long and the Rice Terraces of the Philippine Cordilleras, which cover 4000 square miles (man, 4000 is coming up a lot in this post) and were built 2-6,000 years ago, boggle the mind as to what is possible when you have the technology and manpower handy, even in antiquity. Some rather broad definitions would even include the aforementioned Eiffel Tower and our largest skyscrapers in the category of megastructure.
Of course, this science fiction post is not about what we’ve already done, but what we could do in the future, given enough time, labor, and the (as of right now) miraculous level of technology required for these marvels of technological achievement: Stars surrounded by a cloud of solar panels to generate enough electricity for a interplanetary civilization. A battle station the size of, but is no moon, capable of destroying planets. A spaceship big enough to carry every Mormon alive to another solar system and beyond on the holiest of mission trips. These are but a sampler of a future where resources are plentiful, plans and goals are grand in scope and scale, and the tensile strength of most known construction materials can be hand-waved away.
“Rendezvous with Rama” by Arthur C. Clarke
Megastructure type: O’Neill Cylinder
Dimensions: A cylindrical space vessel 50 kilometers long, 12 kilometers in diameter
Handwaviness: 85% Centripetal force as a gravitational surrogate is feasible! Giant space cities capable of interstellar travel? Not so much.
After a meteorite strike in Italy, the ever-vigilant Spaceguard formed to detect and defend against further potentially deadly cosmic projectiles finds a fast-moving, perfectly smooth, cylindrical object entering our solar system. As further observations of Rama, as it comes to be known, reveal its extraterrestrial origins and purposeful construction, the crew of the Endeavor are dispatched to discover the mysterious interior of the vessel. As Rama approaches the inner solar system, changes in the eons-dormant vessel lead to perilous expeditions in metropolis-dwarfing cities, strange encounters with biological robots, and the paranoia of humans outside the vessel, for Commander Norton, Jimmy Pak, and others aboard the giant cylinder.
Sound familiar? If you follow astronomical news, a somewhat similar story emerged in 2017, as an object detection program discovered a fast-moving, extrasolar, cylindrical asteroid entering our solar system. Unlike the novel, this piece of space rock was only about a kilometer long at most, was not moving nearly slow enough for us to send a ship to it, and did not (to our knowledge) contain a rich and mysterious alien world filled with biorobots. It has since been propelled out of our solar system, currently headed to parts unknown, pointed vaguely in the direction of the Pegasus constellation. Rama was an obvious frontrunner for the name of this unique, one-in-a-billion chance object, but was officially named ʻOumuamua, meaning “first distant messenger” in Hawaiian.
“Ringworld”, by Larry Niven
Megastructure Type: Ringworld (who could have guessed?)
Dimensions: A ring-shaped edifice 1 million miles wide and a diameter close to 186 million miles (approximately Earth’s orbit), with 3 million Earths’ worth of livable land area
Handwaviness: 99% The sheer scale beggars belief, and the materials needed to construct a ring even a millionth of this size is so far beyond our grasp as to be fantasy. Still cool though.
Dwelling deep within an ennui that can only be formed by centuries of boredom, Louis Wu is offered the chance of many, many lifetimes: explore a newly discovered alien structure at the request of another alien empire, discover its secrets, and be rewarded with a ship a thousand times faster than any human vessel. Eager to take on this task, and unable to stop drooling over the change of pace, Wu, along with his crew of a supernaturally lucky human, a cat-like warrior, and the two-headed, three-legged financier of the mission, heads to the eponymous Ringworld, to face whatever perils and bounties await.
This novel is a cultural touchstone when it comes to megastructures in science fiction. After all, it’s up there as one of the biggest! The idea of a purely artificial world so vast as to have not just a planet’s worth of landmass, all filled with the same level of details, features, and wonders as our own planet, but millions worth, is quick to capture the imagination through sheer awe. “Ringworld” has gone on to inspire many more iterative, inspirational, and derivative works, the most popular of which being the “Halo” series, which, while not as large as Ringworld, held enough enrapturing lore and possibility to fascinate teenage-me (and distract me from far too much high school homework).
“Leviathan Wakes” by James S.A. Corey
Megastructure Type(s): Various, including hollow asteroids-turned-space-stations, the aforementioned Mormon spaceship (it’s really important to the story, I promise), and strange alien constructions
Dimensions: Various
Handwaviness: 65-1000% I think we could definitely get the Mormons (among others) to space, and build habitats within large asteroids. The rest is, as Arthur C. Clarke put it, “indistinguishable from magic.”
When investigating a distress signal, James Holden and his crew of ice-haulers are attacked by an unidentified vessel. On Ceres, grizzled Detective Miller gets an under-the-table job to find a missing heiress. The United Nations of Earth, the Martian Constitutional Republic, and the Outer Planets Alliance stand at the brink of war. It’s up to Holden, Miller and others pulled into this web of interplanetary subterfuge and shadow-wars to connect the dots as to who, or what, is behind the tensions before it boils over into a conflict that will scour the surfaces of Earth, Mars and beyond.
This novel, and its subsequent series of sequels, is a space opera by every metric: interplanetary political intrigue, alien encounters, massive spaceship battles and a crew of in-depth, complex, and brave characters ready to face it all. And being so epic in scope leads to a huge variety of megastructures! At every turn of the page you, dear reader, will encounter ships larger than cities (which may or may not contain Mormons), asteroids whose internal hollows are home to millions, and even more, stranger edifices that would be the biggest of spoilers if I were to detail them to you. This novel series, as well as its TV adaptation, is well worth the read, watch or listen.
Eager for more really big things in space? Check out my booklist on the subject here.
