Potential Mineral Resources on the Moon
Authors: Oetking Philip , Jonah Frederick 
Published: December 2007

Introduction

Both the United States and the Soviet Union are rapidly approaching one of the most outstanding feats in the history of mankind-the landing of a man on the lunar surface. On the eve of this supreme challenge. we are faced with the question-what do we know about the moon? Despite a wealth of data derived from lunar observations, the origin of most surface features remains controversial; and almost nothing is actually known of the moon's internal composition, structure or thermal history. Within these restrictions, an attempt will be made to suggest some of the possible mineral resources that may be found on the moon.On earth, it is generally thought that mineral deposits as they are found today are not a part of the primordial earth and that the processes by which they were formed are still active. Many factors, such as temperature, pressure, structure, host rock and mineral source areas, play a role in determining the kind of minerals that will form and where they will tend to localize. Is it not reasonable to assume that the moon will contain many minerals similar to those on earth and that they may be concentrated by similar processes? In the absence of definitive data, this elementary empirical approach is the only feasible one.In order to establish a comparison of the lunar environmental conditions with those existing on earth, the known facts about the moon will be summarized to reacquaint the reader with the type and quality of the available data. The scope of this paper does not permit a review of the various theories postulated for the origin of the many surface features, except where they may he salient to concepts related to mineral occurrences.

Accepted Facts About the Moon

Calculations

Some general astronomical observations and calculations give values for a number of the parameters with acceptable accuracies.The mean distance from earth to moon is approximately 239,000 miles.The mean diameter of the moon is 2.1 60 miles.The moon's density is 3.34 gm/cm (earth 5.51 gm/cm).The mass of the moon is approximately 1/80th of the mass of the earth.The gravitational attraction of the moon is about one-sixth thatof the earth.Rotational and orbital velocities are such that the lunar day and night are each equal to about 14 earth days.The escape velocity at the surface of the moon is about 1.5 miles/sec compared to approximately 7 miles/ sec for the earth.

Observations

Surface features on the earth-lacing side of the moon have been viewed for thousands of years, observed through telescopes since 1609 and photographed repeatedly during the past 100 years. Even with large aperture telescopes and the best seeing conditions, visual observations have a resolving power of only about 0.1 sec of arc. This is about four times better than the best photographs, which correspond to about 1/2 mile. Parts of the far side of the moon, that side which is never visible from earth, were photographed by the Russian Lunik Ill. These photographs are the only records of the back side. The resolution is extremely poor, and only the most general features can be identified.The topographic features of the moon's surface, such as high mountain ranges, circular pits, linear zones, broad dark areas called maria, and light-colored radiating rays. have been mapped in considerable detail. The relative heights are determined with a fair degree of accuracy by measuring shadow length at known sun angles. This is most easily done near the terminator, that area of the moon which is at the junction between light and dark.

JPT

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