~channeling my inner J.Verne, again~
We will live in tubes of carbon bubble wrap that barrel-roll along the asteroid belt, shrouded by a spinning chandelier laced with magnetized Alnico. Yes, that sounds crazy. Here is why we’ll do it:
- We Need Back-up — though robots will do most of the work in space, making a human presence redundant and risky, we’ll still want people off-Earth, in case anything horrific happened down here. Sometimes, redundancy is good. We’ll bring plant and animal samples, too.
- Autonomy — each new space habitat will be like its own nation. Off-world will be like the New World, ripe for zealous pilgrims and entrepreneurs.
- Classism — the cost of entry to space is a barrier to the riff-raff. Elites will feel safer, being far from all the villagers’ pitchforks.
And here is how we’ll do it:
- No Planetary Colonies; Cylinders Instead — the fuel and equipment costs for repeated re-entry and escape velocity make planets unattractive. And, their partial gravity is unhealthy; better to live in the Earth-like artificial gravity of a spinning cylinder, like O’Neill’s.
- Carbon — when we mine asteroids and moons, we’ll produce plenty of carbon, which isn’t worth sending back to Earth. However, it is the ideal architectural material for a spinning cylinder space habitat. We’ll build everything out of carbon nanotubes, graphene, and a few other metallic monolayer structures.
- Iron — asteroid mines will also produce excess iron, which is fine, because we can magnetize it. By attaching these permanent magnets to a twirling net around our spinning space cylinders, we deflect harmful particles. This is cheaper and more fault-tolerant than NASA’s design for a cryogenic cooling system and superconducting electromagnets. A solid shell of magnetized iron would be handy for absorbing gamma rays and flying rocks, too.
- Bubble Wrap — our spinning cylinder colonies will need safety precautions. Suppose a stray pebble, traveling at relativistic speeds, punched a hole through the side of the space station? We’ll build with extreme redundancy. Each room, hallway section, exterior wall, is its own ziploc bubble, able to seal in an instant should an adjacent passageway depressurize. The cylinder walls and outer layer are graphene bubble wrap, too, cushioning against impacts without tearing.
Why a Spinning Cylinder?
Tensile strength is vastly superior to compressive strength. The highest quality concrete can sustain 70 MPa (or, 7,000 tons per square meter of cross-section) of pressure, while carbon nanotubes can dangle 63 GPa. (That’s 6.3 million tons per square meter — almost a thousand times stronger than concrete!) Tensile strength is great for structures made of cables, fibers, or sheets. Blimps and bridges could be gargantuan if made of carbon nanotubes and graphene. Carbon bubble wrap would be bulletproof.
So, graphene bubble wrap protects against a pelting of space pebbles. And, if a space station used many layers of bubble warp, then the gasses contained in each bubble would help absorb cosmic rays. How many layers of bubble wrap? I suggest using an entire roll of it.
As this massive bubble wrap cylinder spins, it generates layers of artificial gravity. At the outer shell, apparent gravity would be slightly greater than Earth’s, and each inner layer of the roll would experience less gravity, until the axial core of the cylinder, which feels no gravity. All of these layers would have purpose, with living quarters along the Earth-like outer layers, and personal storage and industry toward the zero-g core.
This is distinct from O’Neill’s spinning cylinder design, as well as the Stanford Torus and others dating back over a century. Those other designs focused on a single inhabited layer along the outer rim, and a rigid protective shell. In contrast, these bubble wrapped, in-filled cylinders will have thousands of inhabited layers — super-massive apartment complexes. And, being cushioned, flexible, the innermost regions will be perfectly safe from cosmic rays, debris, and large impacts. (Each bubble does need its own semi-rigid frame, like the carbon cousin of Styrofoam, to dampen an impact’s massive pressure wave… that’s always something to worry about.)
On the outermost shell of these bubble wrap worlds, carbon ribbons hold overlapping plates of magnetized iron, blended with aluminum, nickel, and cobalt. Hung from these plates, swirling out around the cylinder like a figure-skater’s arms, are carbon threads on coat hangers, webbed and beaded with more magnetized iron. Together, these iron necklaces and plates are the first defense against the hazards of space, in a form that is redundant and easy for spiderbots to repair.
Why the Asteroid Belt?
Once these cylinders go into production, each misunderstood religious sect and resort cruise company will have a bubble wrap habitat at the location of their choice. Orbit the Earth, anchor around Venus, or wobble along the L4 Lagrangian, you pick. Yet, most of these cylinders will park their equipment next to choice asteroids and micro-moons, with the aim of constructing more spinning cylinders; the faster you churn rock into habitat, the more real estate you have. It’s definitely cheaper than launching a space station from Earth.
When you spot an asteroid, you fire a mining bag. Like a net gun, you send a solid sheet of carbon speeding through space to envelope and constrict the asteroid. Yet, that net carried passengers. With a grip around the rock, crawling mass drivers position themselves to launch microscopic tidbits of iron into space, to generate thrust. They aim their catch to intercept your spinning cylinder habitat; at any given moment, many of these mining bags lurch chunks of rock homeward. Once a mining bag snags onto your cylinder habitat, small drill robots climb inside, so that no dust escapes into space as they separate the material for processing. Mining bags are a stomach for rock. Carbon and iron become new real estate, while precious metals are sent to Earth. Like a gold rush, cities spring up around herds of these rocks.
The larger asteroids, particularly metallic Psyche, will be completely encased in carbon bubble wrap, with a partial atmosphere puffing them up like marshmallows. Robots will mine down underneath the bubble wrap, while people drift adjacent in spinning cylinders. The cylinder habitats won’t be proficient at rapid acceleration or maneuvers; they’ll keep to gentle elliptical orbits, unless there is some reason for them to deviate…
Once enough cylinders are in close proximity to each other, there is a network effect: any goods or services that you might want are most likely found there, especially spare parts. Visitors are more likely to come to your hub of cylinders, rather than a lonesome habitat floating on its own orbit. By intentionally migrating, cylinders that had captured carbon-rich rocks could trade for iron and nickel from Psyche without a long wait or high cost. Each cylinder, its own city-state, will be drawn closer to the others. Separate islands will tug into an archipelago.
Only shortly after the first habitats and mining rigs are assembled and launched, asteroid mining capacity will double, and double again, while gathering together, until all major asteroids are clustered in gentle orbit around Ceres, herded there by foam rolling pins miles wide.