Space-Based Economy Level Four:
Space Resource Utilization
As markets develop for refueling and repair of spacecraft, it will make sense to extract resources from the Moon. What might be the sequence of this process?
1. The first resource on the Moon is solar energy - available at an intensity which is close to ten times as high as on the surface of earth (no atmosphere to absorb it). The initial devices on the Moon will have Earth-built solar collectors and converters - either solar cell arrays or other types of devices.
2. The second resource is lunar "regolith" (soil). Rich in oxides such as silicon dioxide and metal oxides, perhaps with trapped gases.
A portable solar-powered set of explorer / prospector rovers and construction machines may be landed there to prepare suitable sites and dig out valuable ores- using telepresence from Earth to control activities.
3. The third "resource" is nothingness, close to a surface - the vacuum of Space, suitable for vacuum deposition processes. A set of "solar plant generator" rovers would be landed at the chosen sites. These devices, described by Ignatiev and Criswell, will carry a supply of certain substances used in solar cell manufacture. They would roll, under solar power, slowly over a smooth surface, melting the surface layer by focusing sunlight down. With the on-board "impurities" deposited carefully, the melted layer would be converted into solar cells.
Professors Ignatiev and Criswell have done extensive studies on this process, and are confident that large-scale solar-power plants can be built this way, the rovers slowly going about their job during the lunar day.
4. A year or so after solar plant construction begins, there may be enough capacity to run other operations such as open-pit mining and metal extraction. It is not clear at this point, whether metal extraction processes such as the Bessmer process for steel manufacture are the best route - or whether techniques which demand greater amounts of energy are better - since direct beamed solar energy is so plentiful and free.
As metal extraction processes, large amounts of processed regolith will become available for other uses - such as building radiation shields for habitats on the Moon, or to be shipped off into Space.
5. A robotic plant to fabricate metal parts such as cables, sheets and rails - again using solar heating for furnaces, and solar-generated electricity.
7. A concrete plant which uses the loose regolith and solar-powered sintering to build blocks of specified shape and size.
8. Construction robots would be taken to the Moon to build the beginnings of rail tracks for a lunar launcher using the metal (steel or titanium) and the concrete.
9. Electrical windings and capacitance plates would also be fabricated at the robotic factory, to develop the electric system for the e-mag launcher.
10. A system to land material and objects at the lunar surface using tethers would be developed by now.
11. Launcher carriage parts may be sent from earth, to be joined to the carriages built on the Moon. Robotic manipulators would set the carriages on the rails and push them off.
Now lets see reports generated on the prospects for resource utilization
1. BOEING/NASA COMMERCIAL SPACE TRANSPORTATION STUDY Last updated 1/4/1997
Section 3.9 Extraterrestrial Resources, Commercial Space Transportation Study
"Use of ET resources will probably occur first in space, where they would be used to enhance planetary exploration, lunar base development, or other missions. Since they are used in a support role for other missions, the market for ET resources is highly dependent on the market for the primary missions. Use of ET resources is likely to decrease rather than increase the net space transportation demand for any given primary mission."
Comment: That may be so, if the objective is simply "exploration", to the complete exclusion of long-term commercial benefits.
"Returning platinum group metals to earth seems possibly promising. Lunar oxygen has potential but doesn't have many existing potential customers. Helium 3 is not promising any time soon. "
Other odd links:
Earth-Crossing Asteroid Web Page: http://www.eecs.wsu.edu/~hudson/Research/Asteroids/index.htm
http://www.space-frontier.org Space Frontier
NASA Thesaurus -- Products and Resources
Resource List of Commercial Space Material
Using Space Resources
Applied Space Resources
Canadian Space Resources Page
http://www.tlrc.com/ Lunar Resources Company
http://www.aticourses.com/space.htm Space & Aerospace Information Resources, ATI Inc