1. Investing on a temporary and then permanent basis of increasing size is economically sustainable
The Moon, about 384,400 km away from Earth, has not been visited by humans since December 1972, but will be soon. Projects such as Artemis see several space powers involved in what will be man's first return to the Moon. Such missions, as well as future bases that will be installed on the lunar soil and subsurface, must generate a cash return in order to progress to permanent bases.
The Moon is mineralogically uninteresting compared to the asteroids, but the soil is rich in regolith and all the elements to create concrete are also present. The regolith would be employed to protect the facilities and personnel from rocks, fine dust and weathering. The most suitable places to install the base would be caves or drained underground lava channels, and it will be preferable to stay on the poles so that the six-month day/night cycle can be used to optimize the use of solar panels. In addition, there is a low percentage of ice in the lunar regolith, which can be separated into oxygen and hydrogen to fuel the rockets, thus becoming the first cog in the mechanism that will lead to an initial orbital storage system available for other ongoing missions in space.
The increasing autonomy of the lunar bases, the revenues produced by the extraction of regolith and helium-3 from the refueling stations, and the investments of private individuals, will be crucial to ensure the human permanence in space that, although expensive, would be around a value equal to that of the ISS, in an investment spread over ten years. The growing importance of the space economy in sectors such as energy, raw materials, communications and transport, together with the investments of the super rich and ambitious projects such as Mars, will guarantee an enormous economic return to the first countries to set foot on lunar soil.
2. The risks posed by the lunar habitat for human presence
The moon's atmosphere is so thin that it is called an exosphere. It can only contain 100 molecules per cm^3 (Earth, at sea level, contains 10*10^19 per cubic cm). Since the Moon does not have an atmosphere, it is subject to violent temperature variations between the side where it is illuminated and the opposite side, another reason to establish bases around the poles, abandoning them during periods when it is night. The exploitation of regolith will be crucial to protect, using 3D printing, the structures from temperature changes, micro-meteorite impacts and radiation.
The Moon is also rich in ancient dried-up rivers where lava flowed, ideal sites for a base; larger craters can also provide the same kind of protection, as well as a kind of "micro-climate" that does not vary the day/night cycle within it. The main challenge will be to ensure a permanent supply of water extracted from the regolith and to find an effective way to balance the exploitation of solar energy with that of other sources, including nuclear fission, to ensure energy autonomy even during the lunar night. The risks also affect the movements, both of personnel and materials, since the Moon has a very weak gravitational field and a steep terrain, in addition to being rich in fine dust that can damage machinery. The delivery of supplies, and their dispatch, will instead be implemented through electromagnetic catapults installed on the Moon, and with modules with a parachute for the delivery of supplies to the bases.
3. The economic and commercial benefits of a permanent base on the Moon
The race for the Moon will be the new gold rush. Starting with the exploitation of regolith as a building material and as a basic resource for the sustenance of every activity on the Moon, including agriculture, every resource and scientific project will be able to produce a large profit, which will guarantee the sustenance of the mission and an exponential increase in the resources available for the expansion of the lunar bases. The exploitation of the Moon as a supply and resource extraction facility, combined with the fact that the Moon has no interference in the radio spectrum, will allow excellent investment opportunities for the private sector. The import/export, if regulated by the current legislation on international trade and sale of goods, would guarantee a greater economic return for the richest and most developed countries in the space sector, that with joint programs would be the first to appropriate the resources. Countries such as the United States, for example, already have national legislation on the exploitation of space resources, and are very keen to have full autonomy on the possibilities of appropriation of space resources, seeing themselves as a leading country in the sector, as can be seen, ex multis, from the Hearing Before The Subcommittee On Space, Science, And Competitiveness Of The Committee On Commerce, Science, And Transportation United States Senate.
After a necessary rewriting of the articles on the exploitation of space resources indicated in the 1967 Treaty on the Use of Space, which currently prohibit their exploitation for non-scientific purposes, investments on the Moon will ensure, after many decades, a commercial hub that will facilitate future space missions and make it possible and economically viable to turn our gaze towards Mars.
Our civilization, in order not to stop its technological development due to lack of resources, will have to invest as much as possible in the space sector, being now the Moon and the NEO asteroids the most convenient sources for the extraction of resources that on Earth are scarce and have increasingly high costs, also from an environmental point of view. Within our life expectancy it will be possible to look at the Moon and see the same lights that we see from the airplane when we pass over a city.
 A 2013 study by NexGen Space LLC, partially funded by NASA, presents a series of case studies designed to provide deductive evidence that an open competition market in the space sector will lead to investments beyond the reach of individual states, even in sectors that have been monopolized to date.
 The study also describes investment opportunities for private individuals in every branch of the space sector, from existing businesses such as communications and module and spacecraft supply, to rocket propellant production facilities, 3D printing facilities for building construction, tourism, and cargo transport. The study also emphasizes the cruciality of an open-architecture model supply chain to make human expansion into space economically feasible.
Scott Hubbard.New Space.Mar 2016.1-1.http://doi.org/10.1089/space.2015.29003.gsh
Hoppy Price, John Baker, and Firouz Naderi.New Space.Jun 2015.73-81.http://doi.org/10.1089/space.2015.0018
NASA. "NASA’s Journey to Mars: Pioneering Next Steps in Space Exploration." (2015).
Robert Bruce Pittman, Lynn D. Harper, Mark E. Newfield, and Daniel J. Rasky.New Space.Mar 2016.7-14.http://doi.org/10.1089/space.2015.0031
Charles Miller.New Space.Mar 2016.15-18.http://doi.org/10.1089/space.2015.0036
Dennis Wingo.New Space.Mar 2016.19-39.http://doi.org/10.1089/space.2015.0023
Justin Lewis-Weber.New Space.Mar 2016.53-62.http://doi.org/10.1089/space.2015.0041
Ben Haldeman.New Space.Mar 2016.50-52.http://doi.org/10.1089/space.2015.0038
Lynn D. Harper, Clive R. Neal, Jane Poynter, James D. Schalkwyk, and Dennis Ray Wingo.New Space.Mar 2016.40-49.http://doi.org/10.1089/space.2015.0029
Hall, A., & Miller, C. (2016). A Summary of the Economic Assessment and Systems Analysis of an Evolvable Lunar Architecture That Leverages Commercial Space Capabilities and Public–Private Partnerships. New Space, 4(1), 4–6. doi:10.1089/space.2015.0037