Yes, my friends, it is time for another installment in my ongoing series. For those of you just joining us, I am preparing for this year’s National Novel Writers Month challenge by sharing with you, the good readers, the world building and back story for the novel I will attempt to write in November. This will be a Space Opera style Sci-fi story set in a far away future where humanity has spread out to planets beyond the Solar System. In the last post I briefly described the events leading up to the first wave of interstellar colonization.
At this juncture I’d like to take a some time to discuss the reasoning behind some of the choices I’ve made to this point. I may even give some hints about what’s coming up next.
As I stated in the first post of this series I intend for this novel to be on the harder side of the sci-fi spectrum. This puts certain constraints on the world building elements because I have to be careful to avoid completely disregarding the laws of physics. I can, however, stretch those laws as far as I dare. It also means I have to do some research into what exactly these limits might be. The good news is that the internet has provided some excellent resources. Chief among them are the Atomic Rockets website (which I heartily recommend to any aspiring sci-fi author), the Rocketpunk Mainfesto and Future War Stories blogs, and the massive website of the Orion’s Arm shared world building project.
Truth be told, I considered foregoing the arduous task of constructing my own setting and simply asking permission to use the one from Orion’s Arm. It is already highly detailed, immensely complex, and rigorously grounded in actual science. However, they make some assumptions in their future timeline that takes their technological and sociological development in directions I did not want to go. They are not objectionable developments in the least. In fact, I was inspired by and borrow from many of their ideas. I simply have different base assumptions for my setting. Some of these differences I will share later.
I decided early on that I wanted a good handful of separate societies interacting in my setting. Each ark will set off for a different system and found their own distinct culture. That would give me 6 factions total when I include that of Sol system. Having decided that, I then had to decide a number of other details. First, how would these colony ships be constructed, and how would they be propelled? Second, where would they go? And, finally,where would the colonists come from? This post will focus on the first question.
The Five Arks
The Arks themselves are inspired by an image I once saw of a community built within a hollowed out asteroid. Then again, maybe it was a Star Trek episode. In any case, this seemed like a fantastic way to build a colony ship. Then I found this article on the website for Icarus Interstellar and my ideas solidified. If one uses icy bodies, basically enormous balls, or rough cylinders, composed mostly of ice, as the base structure and then hollows them out to provide living space for the passengers, then the ice can serve several purposes. It would provide shielding from cosmic radiation, as well as an an ablative shield against impact by space borne particles and rocks. It would also provide the water and oxygen needed for the internal ecosystem. Finally, the ice would be a source of the Hydrogen and Helium necessary for Fusion Power and propulsion.
The propulsion systems for these enormous colony ships would have to be sufficient to accelerate them to a significant fraction of the speed of light. If not, the journey would still require centuries rather than decades. Even if I posit advances in medical science that extend the human lifespan, this is much too long. I want my colony ships to reach their destinations within the first generation or two, or better yet, within the lifespan of the first generation. While Matter-Antimatter annihilation produces the most energy output by mass, it really doesn’t work as an energy source so much as an energy transfer system. Put simply, one has to expend at least twice as much energy creating the antimatter as one gets out of the reaction. Not to mention that storing the damn stuff is highly problematic.
I have, therefore, settled on nuclear fusion as the basis of my ark ship propulsion. This type of propulsion system produces enormous amounts of thrust from the expelled reaction products. Icarus Interstellar currently bases their interstellar flight proposals on fusion based propulsion. I am going to take a leap here and allow that advances in material science and engineering improve the performance of such systems such that I can get my space arks up to around 0.87c, the point at which time dilation halves the time experienced in the ship compared to that of the origin point.
As mentioned in the previous post, each icy body will be partially hollowed out to provide living space for the colonists, room for necessary control and life support machinery, and space for food production en route. How much space does this require, really? I once again turn to Icarus Interstellar. One article there describes the community planning that they are considering for their Colonized Interstellar Vessel (CIV). The basic idea is that for long duration interstellar journey’s the living space needs to be diverse and somewhat non-uniform to counter the potential boredom that might occur.
Their design is intended for a population of around 10,000. My colony arks have populations in the 100,000 range. Still, this is a far cry from the strictly utilitarian designs I’ve seen elsewhere. Their design is certainly scalable. Furthermore, it gives me a nifty idea for imparting the necessary spin for artificial gravity.
If one were to simply impart a spin on the asteroid then it would be more likely to fly apart due to the low tensile strength of ice. The CIV design consists of eight half cylinders arranged in a ring parallel to one another. Now, imagine this ring embedded within an icy asteroid with a rail or bearing system that permits free rotation of the structure within. Thus, the habitation areas have livable gravity and the outer shell of the asteroid is not subjected to destabilizing forces.
Please, join the conversation. I’d like to hear any opinions or ideas you may have about my project thus far, the concept of interstellar colonization, or the trope as used in Science Fiction literature. Tell me, what is your favorite space exploration and/or colonization story?
In my next post we will consider the question of destinations.