Abstract
Boulder tracks from 19 different locations on the Moon, observable in Lunar Orbiter photographs, have been examined. Measurements of the track width indicate that some of the boulders sank considerably deeper than others. It is suggested that lunar surface materials vary from place to place; the state of compaction (density of lunar soil) is probably one of the significant variables. Using bearing capacity theory, modified to be applicable to the rolling boulder problem by theoretical studies and extensive testing, the friction angle of the lunar soil was estimated. Most of the results were between 24 and 47 degrees with an arithmetic average of 37 degrees. These values suggest corresponding density variations of 1.25 to 2.00 g/cm3.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Eggleston, J. M., Patteson, A. W., Throop, J. E., Arant, W. H., and Spooner, D. L.: 1968,Photographic Engineering 34, No. 3.
Filice, A. L.: 1967,Science 156, 1486.
Grolier, M. J., Moore, H. J., and Martin, G. L.: 1968, Lunar Block Tracks, inA Preliminary Geologic Evaluation of Areas, Photographed by Lunar-Orbiter V Including an Apollo Landing Analysis of One of the Areas, U.S. NASA, Langley Research Center, Langley Working Paper (LWP) 506, pp. 143–154.
Hovland, H. J. and Mitchell, J. K.: 1970,Mechanics of Rolling Sphere-Soil Slope Interaction, Final Report, Vol. II of IV, Space Sciences Lab., NASA Contract NAS 8-21432, Univ. of Calif., Berkeley.
Houston, W. N., Namiq, L. I., and Mitchell, J. K.: 1970,Lunar Soil Simulation, Final Report, Vol. I of IV, Space Sciences Lab., NASA Contract NAS 8-21432, Univ. of Calif., Berkeley.
Houston, W. N., Hovland, H. J., Mitchell, J. K., and Namiq, L. I.: 1972, ‘Lunar Soil Porosity and Its Variation as Estimated from Footprints and Boulder Tracks’,Proceedings 3rd Lunar Science Conf.
Meyerhof, G. G.: 1951,Geotechnique II, 301.
Mitchell, J. K., Bromwell, L. G., Carrier, W. D., III, Costes, N. C., and Scott, R. F.: 1971,Soil Mechanics Experiment, in Apollo 14, Preliminary Science Report, NASA Spec. Publ., NASA SP-272, pp. 87–108.
Mitchell, J. K., Bromwell, L. G., Carrier, W. D., III, Costes, N. C., Houston, W. N., and Scott, R. F.: 1972,Preliminary Analysis of Soil Behavior, in Apollo 15, Preliminary Science Report, NASA Spec. Publ., NASA SP-289, pp. 7-1 to 7–28.
Moore, H. J.: 1970,Estimates of Mechanical Properties of Lunar Surface Using Tracks and Secondary Impact Craters Produced by Blocks and Boulders, USGS, Interagency Report, Astrogeology 22 (Preliminary).
Moore, H. J., Vischer, W. A., and Martin, G. L.: 1972,Boulder Tracks on the Moon and Earth, USGS, Prof. Paper 800-B. pp. B165-174.
Nordmeyer, E. F. and Mason, C. C.: 1967,Lunar Surface Mechanical Properties Derived from Track Left by Nine Meter Boulder, NASA, MSC Internal Note No. 67-TH-1.
Scott, R. F. and Roberson, F. I.: 1969,Soil Mechanics Surface Sampler, in Surveyor Program Results, NASA Spec. Publ., NASA SP-184, p. 171–179.
Terzaghi, K.: 1943,Theoretical Soil Mechanics, John Wiley and Sons, Inc., New York, 14th printing.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Hovland, H.J., Mitchell, J.K. Boulder tracks and nature of lunar soil. The Moon 6, 164–175 (1973). https://doi.org/10.1007/BF02630660
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02630660