Mars In Situ Resources and Utilization for Human Settlement
This paper investigates the availability and means of exploitation of water and carbon dioxide resources on Mars. Current space policy calls for the “return of humans to the Moon for long-term exploration and utilization, followed by human missions to Mars and other destinations.” Elucidation of that intent includes human settlement of space. The daunting reality is that lifting humans, equipment, consumables, and propellants costs an average of $35,000/kg depending on the lift vehicle utilized. Reusable lift vehicles will reduce that cost but due to the cumulative expense, permanent human presence and settlement on the Moon and Mars cannot be sustained indefinitely by resupply from Earth. In situ resource utilization (ISRU) will enable sustainable settlement of the Moon and Mars. Water resources for human consumption, growth of food, production of oxygen to breathe, and production of propellants for space vehicles are the key to sustainable space settlement. Our robotic exploration of Mars has revealed that Mars has an early geologic history of abundant surface water in rivers, lakes, and oceans. Today, surface liquid water cannot exist due to low temperature and low atmospheric pressure. Robotic exploration further reveals that water ice currently exists in abundance in Mars polar regions and in the near subsurface down to mid-latitudes. Studies show that approximately five million cubic kilometers of ice have been identified at or near the present surface of Mars. Gamma ray spectroscopy (GRS) from the Mars Odyssey probe, ground penetrating radar (SHARAD) and HiRISE imaging from the Mars Reconnaissance Orbiter provide evidence and details. Preferred rocket propellants for long term storage are methane and oxygen. The Sabatier process can convert Mars atmospheric carbon dioxide and hydrogen from water ice to methane and water. Water can be electrolyzed into oxygen and hydrogen to be recycled back to the Sabatier reactor. Both processes require more energy than currently proposed small solar arrays or kilopower nuclear reactors can provide. The necessary power could be provided by a scaled version of a portable ten megawatt SSTAR fusion nuclear reactor with ample power to support growing human habitats. This could be designed to fit the cargo capacity of a commercial reusable heavy lift vehicle. Someday, Mars’ uranium resources could feed the reactor and exported propellants could feed the economy of a growing human settlement of space.
AAPG Datapages/Search and Discovery Article #90350 © 2019 AAPG Annual Convention and Exhibition, San Antonio, Texas, May 19-22, 2019