Most people imagine the distant future of humanity like an episode of Star Trek. Queue the cheesy music and hip-hugging space suits. The starship Enterprise is blasting bad guys with its photon torpedoes and settling space colonies that further expand the borders of a thriving United Federation of Planets, teeming with alien civilizations.
But the reality is that our future may not be tied to planets.
Because all of us were born on a planet, we suffer from a deeply ingrained “planetary bias.” Earth has been humanity’s womb, so we naturally expect to settle another spherical body. We think that new horizons are broached with “one small step for man” on a new habitable planet — whether that be Mars or some yet-undiscovered planet that aligns with humanity’s desired ecosystem.
But even though life evolves on planets, celestial bodies are not the best long-term option for supporting technologically advanced civilizations due to their limited resources.
Based on scientists' current interpretation of the laws of physics, the best option for establishing a permanent place for humanity may be something called a rotating habitat.
What is a rotating habitat?
Back in the seventies, physicist Gerard O’Neill spotlighted the concept of rotating habitats, cylindrical megastructures that perfectly replicate Earth’s gravity and atmospheric conditions.
Today, many of the technologies necessary to build them already exist, and — with modern 21st-century materials — they can be large enough to comfortably house tens of millions of people. Even better, you don’t need to make it through NASA’s astronaut program; your eighty-year-old grandmother would be perfectly comfortable living in one of these habitats.
But even if rocket launch costs weren’t still prohibitive, the raw materials to manufacture these dwellings must be acquired in space. Asteroids and the moon will provide the foundation for the initial infrastructure, including the first rotating habitat prototype.
Why not just go to Mars or some other planet?
Aside from the fact that we don’t know yet how to travel at warp-speed, humankind has been extremely optimistic about which planets we’ll be able to settle — never mind the lack of magnetic fields or breathable atmospheres.
The deleterious effects of zero-gravity on human physiology are one of the reasons why the odds of being accepted in the NASA Astronaut Program are 0.065%. In other words, humans do not have the physiology to function well on another planet.
After studying the effects of zero-gravity for nearly 60 years, scientists have begun to understand the disastrous effects of zero-gravity on the human body. We can try to guess the effects of Mars (at 38 percent of Earth’s gravity) or the moon (at 17 percent), but we won’t know for sure until scientists perform actual tests. Some speculate that we’ll need to make severe adaptations to our bodies in order to survive in those low-gravity environments, possibly branching into a different species in the not-too-distant future.
As Earth becomes smaller and smaller with the amount of land to feed our population fast approaching unsustainable levels, our short-term profit system continuing to destroy the planet, pandemics, inequality, political stagnation, and climate change, we ask ourselves, “Can we avoid self-annihilation?”
“The sea level rise created a refugee exodus of catastrophic proportions when hundreds of millions were forced to flee their homelands, as living became impossible in the most vulnerable coastal regions.” -Excerpt from my book K3+
Move over, Mars and Mercury
Mining asteroids can only bring us so far. As the human footprint in space grows, it will be necessary to find more abundant sources of raw materials, like those on Mercury. Being the leftover core of a past planetary collision, it won’t be necessary to dig very deep. The first rock from the Sun is made of 70 percent metals and 30 percent silicates and is perfect for building the first megastructures capable of housing millions. Each of these self-reliant island-sized habitats will be able to feed its entire population and satisfy their power demands.
As Mercury becomes exhausted, the Sun (which contains thousands of times the mass of planet Earth in metals) will take its place as the main source of raw materials for the burgeoning human civilization.
We know these elements are not sunk down to the core but swirling around, carried by the star’s convective process. Even if it requires huge amounts of energy to extract them, the Sun generates a virtually endless supply. Regardless of the technology we develop for this purpose, mining the sun will reduce its mass, delaying the moment it will become a red giant.
Continent-sized rotating habitats, each capable of housing billions, will be constructed as new advanced materials of incredible tensile strength are developed. A few centuries in the future, a population of quintillions will finally level with the power output of the Sun, requiring humans to reach for the stars to find additional room for the growing population.
Will humans change, living inside rotating habitats?
In a single second, the sun produces close to 500,000 times the annual energy needs of our entire civilization. In space, solar panels harvest seven to eight times more energy than on Earth’s surface, and near-future technologies are bound to dramatically raise their efficiency.
Thanks to genetic enhancements, crops can be adapted to thrive in the lower gravity areas of the cylinder — maximizing human use of the habitable surface — and lab-grown meat will produce better steaks without bringing cows to space. In time, it will be possible to grow an apple without a tree while using a fraction of the resources.
AI-controlled and solar-powered laser systems will keep these colonies safe from asteroids and other debris. Radiation shielding can be achieved either by soil, water, or generating a strong magnetic field from superconducting wires in the cold temperatures of space. A system of vacuum tubes, with rails inside, will allow transports to travel at dizzying speeds between the habitats, using magnets.
Within a century, the ever-growing population will be able to live for eons, oblivious to the ravages of aging, in larger and larger numbers of these megastructures. We can fit more people inside rotating habitats around the Sun than on all habitable planets in the entire Milky Way galaxy.
Imagine a single mega-nation, billions of times larger than any other in history, where quintillions of inhabitants live safely and free from fear, inequality, disease, exploitation, and wars — a true renaissance for our species.
We can fit more people inside rotating habitats around the Sun than on all habitable planets in the entire Milky Way galaxy.
Rotating habitats also happen to be ideal for interstellar travel, as they already provide a perfect habitat for humans, requiring only adaptations for the long interstellar journey: shields, brakes, maneuvering thrusters, and power generators, among others. Under a gentle acceleration, induced through solar powered lasers in space, it will take a few years to reach the speed necessary to arrive at Alpha Centauri within decades.
But stuck with business-as-usual, prey to our instant-gratification instinct, obsessed with greed, and fantasizing about war, we fail to realize the universe is a wondrous realm — rife with possibilities for permanent colonies that could provide an exceptional future for civilization.
In the meantime, the cosmos lay empty, its doors wide open, just waiting for us to settle it.
Want to learn more about space colonies?
My new novel K3+ dives deeper into this topic and explores what life could look like as we become a spacefaring civilization.