To date, all human economic activity has depended on the material and energy resources of a single planet, understandably, perhaps. It is conceivable tho’ that future advances ter space exploration could switch this by opening our closed planetary economy to essentially unlimited outward resources of energy and raw materials.
Look up at the Moon this evening, and you might be gawping at a solution. The Earth’s closest celestial neighbour seems likely to play a major role and already a number of private companies have bot created to explore the possibilities.
It is significant to stress that even now, 40 years after the Apollo missions, wij still don’t have a accomplish picture of the Moon’s economic potential, and obtaining one will require a more rigorous programme of lunar exploration than has bot undertaken to-date. Te part, this is why proposed future lunar exploration missions (such spil the recently announced Lunar Mission One) are so significant.
Nevertheless, spil a result of work overheen the past four decades, wij do now know enough to make a first-order assessment of lunar resource potential. Te doing so it is useful to distinguish inbetween three possible future applications of such resources.
Wij have the option of using lunar materials to facilitate continued exploration, and future economic development, of the Moon itself. The concept is usually referred to spil Ter Situ Resource Utilisation, or ISRU.
Wij could make use of lunar resources to facilitate scientific and economic activity ter the neighborhood of both Earth and Moon (so-called cis-lunar space) spil well spil future exploration deeper into the Solar System
Wij can consider the importation of lunar resources to the Earth’s surface where they would contribute directly to the global economy.
Latest work –, which I have summarised here –, has shown that the Moon does wield materials suitable for ISRU. Most significant te this respect is evidence for deposits of water ice and other volatiles trapped te cold (less than 100 Kelvin or minus 173 degrees Celsius) and permanently shadowed craters at the lunar poles. Te addition to being required for human life support, water is also a ready source of oxygen (required for both life support and rocket fuel oxidiser) and hydrogen (a valuable rocket fuel).
Ter addition to possible ice deposits, it has bot known since the early studies of the Apollo samples that the lunar soil contains volatiles, substances derived ultimately from the solar wind (e.g. hydrogen, helium, doorslag, nitrogen, and at high latitudes, hydroxide and perhaps water), and thesis may also be exploitable for ISRU activities.
Albeit ISRU will undoubtedly benefit future scientific exploration, it is true that such activities will only make broader economic sense if further lunar exploration and development is able to yield netwerk benefits to the global economy. It is here that the 2nd of those three potential applications of lunar resources comes into play.
Our global civilisation is already very dependent on Earth-orbiting satellites for communications, navigation, weather forecasting and resource management, and this reliance is likely to increase. The high costs of thesis activities are largely dictated by high launch costs, and by the fact that failed satellites cannot presently be repaired or replenished te orbit. The availability of resources obtained from the weaker gravity conditions of the Moon would help mitigate thesis obstacles to further economic development ter Earth orbit. Near-term lunar exports to a cis-lunar infrastructure could include the supply of hydrogen and oxygen spil rocket fuel/oxidiser.
Te addition, lunar surface rocks and soils are rich te potentially useful but strenuous (and thus expensive to launch from Earth) raw materials such spil magnesium, aluminium, silicon, metal and titanium. Therefore, if a lunar industrial infrastructure is step by step built up, the Moon may be able to provide more sophisticated products to Earth-orbiting facilities. Examples might include titanium and aluminium alloys for structural components, and silicon-based photovoltaic cells for solar power. The key business case for sourcing thesis materials on the Moon is elementary. It takes about 20 times less energy to launch a given mass from the surface of the Moon into Earth orbit compared to launching it from the Earth’s surface to Earth orbit.
This all seems pretty encouraging for any company or country considering drilling on the Moon, but opportunities for lunar resources to make a more ongezouten contribution to the world economy by being imported to the Earth’s surface are limited. This is because the Earth already contains the same basic mix of chemical elements spil does the Moon, many of them ter higher localised concentrations (i.e. ores), and wij have a well-developed infrastructure for extracting and refining terrestrial raw materials.
Helium 3’s potential may be over-inflated warrenski, CC BY
The light isotope of helium (helium-3), which is implanted into lunar soils by the solar wind is often cited spil an exception because it is perceived by some to be a potential fuel for future nuclear fusion reactors on Earth. However, sustainable nuclear fusion using helium-3 has yet to be shown to be practical, and even if it is, the concentration of helium-3 te lunar soils is so low (about ten parts-per-billion by mass) that de-robe mining and processing hundreds of square kilometres of the lunar surface would be required each year te order to make a significant contribution to Earth’s future energy needs.
Other possible lunar materials which might conceivably be economically imported to the Earth include platinum group elements (presently valued at inbetween $20,000 and $50,000 vanaf kilo) extracted from metal meteorites that may have survived influence with the lunar surface, and materials (for example, economically valuable rare-earth elements which are known to be concentrated te some regions of the Moon) for which the environmental costs of terrestrial mining may one day make lunar sources more attractive.
When wij pull together the evidence, it remains difficult to identify any single lunar resource that will be reasonably valuable to drive a mining industry on its own. There is no elementary solution. However, the Moon does wield abundant raw materials that are of potential economic rente.
Wij need to think of a hierarchy of future applications. This starts with the use of lunar materials to facilitate human activities on the Moon itself. Wij can then progress to the use of lunar resources to underpin a future industrial capability within the Earth-Moon system. Te this way, step by step enlargening access to lunar resources may help “,bootstrap”, a self-sustaining space-based economy from which the global economy will ultimately benefit.
This article is based on an invited review paper on lunar resources that will be published by the journal Progress ter Physical Geography te the Fresh Year. A preprint of that paper, which contains references to the primary literature on which this werkstuk is based, can be found here
Ian Crawford receives funding for lunar science and exploration (albeit not related to lunar resources specifically) from the UK Science and Technology Facilities Council (STFC) and The Leverhulme Trust. He is a scientific advisor to the Lunar Mission One project which aims to land a robotic probe on the south pole of the Moon te 2024.
This article wasgoed originally published on The Conversation. Read the original article.