Underhill Mars Base by Euge

Last crawled date: 3 years ago

Underhill Mars Base:
In this model I took the approach of examining both the very large view of what overarching technologies and methods make the most sense to pursue on a permanent mars base, and the very small view of what the life and development at such a base might be like from a human perspective. The name “Underhill” is an homage to the first mars settlement in Kim Stanley Robinson's Red Mars Trilogy, a series of books that I would recomend to anyone, and from which I drew a lot of inspiration.
The tightest bottlenecks to a permanent base on Mars are the high cost of sending material from earth, and the very limited amounts of both freely available energy (solar cells only get 30%-50% of the sunlight available on earth) and key materials on the surface (no convenient lakes or thick atmosphere to pull water from, no mining/smelting infrastructure, etc..). Nuclear power will be the key to figuratively pouring this Mars base out of the proverbial bottle. Mars has a long history of using nuclear power sources in the form of Radioisotope Thermoelectric Generators (RTG’s), like the 125 Watt version on the Curiosity rover. A fission reactor that can output ~3 orders of magnitude more power through the use of several redundant, highly efficient Stirling engines with radiator arrays, opens up a lot of opportunities for using locally available resources that would otherwise be too energy intensive.
The base would be located in a cliff face or a rock outcropping of some sort that presents easy access to an automated tunneling machine. The tunneling machine would bore a series of parallel tunnels into the cliff face, the ends of which will be sealed off to make them airtight. The inner surface of the tunnels will be reinforced with either curved plates, sintered out of the available regolith or by partially melting and fusing the inner surface with lasers directly during the boring process. The many meters of stone and regolith above the tunnels will provide plenty of insulation from the ambient cosmic radiation on the surface. Waste heat from the powerplant will be used to heat the habitat. Using tunnels as the main habitat structure makes adding living, farming and work space to the base just a matter of time and energy, once the initial investment of the tunnel boring machine is made, and can be expected to be a lot more robust and secure than any possible surface structure. The floors of the tunnels will initially come as pre-fabed modular units and will provide plenty of space for all of the necessary plumbing, wiring, and life-support infrastructure. All of the food can be grown hydroponically in specialized tunnel sections with the aid of artificial LED lighting for optimal productivity.
Some initial amount of water and oxygen will be brought from earth, the rest can be extracted from the thin atmosphere and from the rocks excavated during the tunnel construction. Spare parts and new machinery can be limited to electronics, optics, and extremely intricate components, the rest can be 3D printed on the spot out of metal or plastic as needed from a common stock of raw printing material. To close the loop, any broken or no longer needed components (such as parts of the landing vehicles) can be recycled by grinding and reprocessing them into raw 3D printing material.
Once the initial, minimal base is established in the tunnels, a larger, external common structure can be constructed out of inflatable components, reinforced with sintered regolith blocks. This common structure would unify all of the disparate tunnels, and provide a place for the inhabitants to gather, share meals and entertainment, with plenty of windows onto the surface of Mars.