ALPH: A Low Risk, Cost Effective Approach for Establishing Manned Bases and Colonies on Mars

Abstract

Current thinking envisions manned expeditions from Earth will carry all the supplies for the astronauts on Mars, plus the propellants and supplies for their return to Earth. For each Mars mission, many hundreds of tons must be launched into space at great cost. The drive to minimize weight and cost reduces the margins of safety on supplies and equipment. A new approach is proposed that could greatly reduce the risk and cost of manned missions to Mars and lead to practical colonies there. The ALPH approach lands a small robotic, nuclear-powered unit on the North Polar Cap of Mars. Using H2O surface ice from the Polar Cap and CO2 and N2 from the Martian atmosphere, ALPH manufactures and stockpiles virtually all of the supplies and habitats for a manned base on Mars, including liquid H2 and O2 propellants, breathable air (80% N2 and 20% O2), methane and methanol fuels, water, polymerized plastics (e.g., polyethylene, etc.) and high-protein algae and yeast foods. The materials are stockpiled in cavities inside the Cap, created using waste heat from the reactor. Additional cavities serve as habitats for the arriving astronauts, to shield them from cosmic radiation. The sub-surface rooms are thermally insulated by plastic foam and heated by waste heat from the reactor, which supplies electricity for lighting, life support, and mission operations. Using rovers and flyers, the astronauts would explore the Polar Cap and other areas on Mars. Ice cores from the Polar Cap would provide a detailed past history of Martian meteorology, atmospheric composition, dust transport, cosmic ray activity, volcanic and asteroid impacts, evidence of bacterial and other life forms, etc. A baseline design for the first ALPH mission is described. The nuclear reactor and process technology for the ALPH components is well developed commercially. The compact 1 megawatt(e) reactor uses zirconium/UO2 cermet nuclear fuel and water cooled/steam cycle technology. The mass of the ALPH factory unit, including nuclear reactor, power system, and process units, is approximately 5 metric tons. In the 20 month period before the astronauts left Earth, ALPH would stockpile 160 tons of liquid hydrogen, 1660 tons of liquid oxygen, 100 tons of liquid breathable air, 60 tons of liquid methane, 30 tons of liquid methanol, 30 tons of plastics, and 10 tons of foodstuffs. In addition, ALPH would create 8 sub-surface cavity habitats, each 9 meters in diameter and 5 meters in height. Subsequent ALPH landings would establish a permanent colony of hundreds of people on the Polar Cap. The colony could transport propellants and supplies from Mars back to High Earth Orbit, to support future trips to Mars and a large space infrastructure linked to Earth.