What is a space habitat? A space habitat is a type of space station intended to be a permanent settlement. It is not a way station or specialized facility. Space habitats may include space colonies constructed on or in a body beside Earth. Progress toward a space faring society requires a space habitation paradigm. How would we build a roadmap for space habitation?
The roadmap for space habitation would include considering the humanities such as space education, public outreach, space law, space policy, astrosociology and space economics, the sciences of astrobiology, astronomy, cosmochemistry, space medicine, planetary science, and space agriculture, as well as technologies focused on space energy, space architecture, space communication, space robotics, astrodynamics, structures and materials, and life support.
We know with nineteen (19) trillion miles across just our Milky Way galaxy to explore with new powerful telescopes and robotic and human missions, it is no wonder many scientists feel a deep spiritual sense of awe and reverence for our 13–15 billion year old Universe. Our Universe may hold an incalculable 200 billion (2x) stars. There are at least 400 billion stars in just our own Milky Way galaxy to explore the oceans of space as Carl Sagan termed expanding our galactic voyages in his spellbinding epic Cosmos (1980) book and TV series.
Science fiction may become science fact in the twenty-first century if we know who we are, where we are, where we have been, and where we are going with technology as a force to pursue happiness reduce poverty, competition, and control as we move deeper into and begin to inhabit space.
Science fiction is history of the future and it is often prophetic. A space habitat has not yet been constructed though many design concepts have been introduced by engineers and science fiction writers. Jules Verne’s From the Earth to the Moon (1867) is considered the first of the Victorian Industrial Age epics dreaming of sending a human to the Earth’s moon.
Deaf scientist Konstantin Tsiolkovsky’s Beyond Planet Earth (1903) detailed rotating cylindrical space colonies with plants fed by the Sun. Inspired by Verne’s writings, Tsiolkovsky foresaw multi-stage rockets, space stations, inter-planetary travel, and the development of agricultural farming and asteroid mining in space.
In the 1920s, John Desmond speculated about giant space habitats. In several magazine articles and books of the Fifties and Sixties such as Islands in Space: The Challenge of the Planetoids, Dandridge M. Cole describes the hollowing out of asteroids and rotating them for use as space settlements. Such prophetic visions paved the way for creators and inventors like Robert Goddard, the father of liquid propelled rockets.
The Columbia Broadcasting System (CBS) fictional radio broadcast of H.G. Wells’ War of the Worlds (1898) on October 30, 1938 scared Americans into believing Earth was being invaded by Martians who were then finally destroyed by microbes. Cold War era comic books, art, television, and film document our ongoing cultural fascination with imagining outer space science fiction.
Modern science fiction writers have created intriguing fictional space societies. These include the Japanese Gundam Universe and space stations Deep Nine and Babylon Five. The film Elysium (2013) takes place on a luxurious rotating wheel of a space station following Earth’s destruction. In Interstellar (2014), the main character wakes up on a space station orbiting Saturn. We are still captivated by the possibilities of space habitation and colonization.
Reasons for space habitation and space colony building include:
- Survival of human civilization and the biosphere in case of disaster.
- Vast resources in space to expand human society.
- Expansion without destruction of ecosystems and displacement of indigenous peoples.
- Relieve population pressure and remove industry from Earth.
Near Earth space habitats provide the following advantages:
- Solar energy. Solar cells or heat engine-based power stations can convert sun light to electricity to provide light for plants, warmth for space colonies, energy for solar sails, and to process ores in mining.
- Colonies orbiting Earth would not have the challenging gravity well of distant planetary colonies trading with Earth.
- Colonies in space could be supplied with oxygen, drinking water and rocket fuel thru in-situ resource utilization mining on asteroids, the Moo, or Mars.
- Asteroids without substantial gravity wells permit mining and hauling to a construction site. The main asteroid belt has enough resources for space habitats to cover the habitable area of 3000 Earths.
- Free floating material in the main asteroid belt could relieve population pressure and sustain trillions of people.
- Rotation axis areas in space habitats would allow zero g sports like swimming, hang gliding, and human powered air crafts.
- The passenger compartment of a large spacecraft or generation ship will permit colonization of asteroids, moons, planets, and stars.
Space habitats must provide all materials needed by hundreds of thousands of humans in a space environment hostile to humans.
1. A 78% carbon dioxide-nitrogen and 21% oxygen mixture is needed for any space habitat. Nitrogen can come from Earth and in liquid ammonia form from lunar rock, comets, and moons of other planets in our solar system. Space colonies could recycle air thru photosynthetic gardens, hydroponics, or forest gardens. Catalytic burners like those used in nuclear submarines could remove industrial pollutants like volatile oils and excess molecular gases. Cryogenic distillation systems could remove mercury vapors, noble gases, and other impurities.
2. Organic materials for food production must initially be provided from Earth. Cryogenic distillates, plants, garbage, and sewage could be combined with air in an electric arc to create carbon dioxide and water for use in agriculture. Nitrates and salt from ash dissolved in water can be separated into pure minerals. Nitrates, potassium, and sodium salts could be recycled into fertilizer. Chemically purified minerals like iron, nickel, and silicon could be used in industry.
3. Long-term zero gravity in orbit weakens human bones and muscles, harms immune systems, calcium metabolism, and sinuses, and causes stuffed noses and serious motion sickness. Rotating colony designs use inertia to simulate gravity. People can live comfortably in a space habitat with rotational radius greater than 500 meters and less than 1 RPM and experience dealing with centrifuge spin.
4. The structure and air of large space habitat designs can shield humans from cosmic rays. Smaller habitats could use stationary bags of rock as shields. Sunlight could be admitted indirectly using mirrors in radiation proof louvres. Magnetic or electric fields can deflect cosmic ray particles. Space habitats outside of the Earth’s magnetosphere would put residents in the way of proton exposure from solar wind.
5. In the vacuum or thermos like space habitat, a central radiator can eliminate heat from sunlight and distribute coolants like chilled water.
6. The space habitat would need a thick atmosphere and radar sweeps to protect itself against meteoroids, dust, and debris. The O’Neill/NASA Ames “Stanford Torus” use non-rotating cosmic ray shields of packed sand or ersatz concrete. An external radiation shell of multiple layers will best protect space habitats against meteoroids.
Space habitat considerations include:
1. Cheaper launch costs or a mining and manufacturing base on the Moon are needed.
2. Electromagnetic tether propulsion or mass drivers as rocket motors make up the designs of most space colonies.
3. Low energy approaches to the Earth and Moon will allow quick inexpensive access to raw materials and major commercial markets.
4. Precession or O’Neill’s two (2) cylinders used as momentum wheels can roll the colony’s angle toward the Sun.
5. Space habitation requires overcoming long-term challenges such as zero gravity and radiation exposure.
6. Our goal must be permanent human habitation of worlds on stations outside Earth.
Forthcoming articles will focus on space habitat concept studies and models. Stay tuned.