In Situ Utilization of Indigenous Resources

Abstract

Planning for a human mission to Mars dates back to the 1950s, but in the 1990s, a new aspect was introduced: In Situ Resource Utilization (ISRU). In its simplest form, it utilizes indigenous Mars resources to produce propellants for ascent from Mars, thus significantly reducing the mass that must be transported to Mars. If accessible water can be found at a suitable landing site, or if hydrogen can be efficiently transported to Mars, not only ascent propellants, but also water and oxygen for life support could be produced on Mars. In the absence of accessible hydrogen, CO2 in the Mars atmosphere can be electrolyzed to produce oxygen, representing about 78 % of the required total mass of ascent propellants. While lunar ISRU has been claimed by some to be a steppingstone to Mars ISRU, we show here that there is relatively little connection. Furthermore, lunar ISRU has far less mission benefit, and does not appear to provide any return on investment. After years of investing in lunar ISRU, which has not led to much more than impractical concepts, and decades of providing very little funding for Mars ISRU, NASA finally provided significant funding for Mars ISRU in 2014. NASA chose to fund a flight demonstration for the 2020 Mars lander of technologies that were quite immature. Had NASA funded a laboratory program to maturate the needed technologies prior to flight hardware development, the whole process would have been far more effective, and less stressful.