The moon

, Volume 2, Issue 3, pp 263–278 | Cite as

A mechanism for the production of lunar crater rays

  • Verne R. Oberbeck


Observations of high resolution photographs of part of one of the prominent rays of the lunar crater Copernicus show that there is a concentration of small bright rayed and haloed craters within the ray. These craters contribute to the overall ray brightness; they have been measured and their surface distribution has been mapped. Sixty-two percent of the bright craters can be identified from study of high resolution photographs as concentric impact craters. These craters contain in their ejecta blankets, rocks from the lunar substrate that are brighter than the adjacent mare surface. It is concluded that the brightness of the large ray from the crater Copernicus is due to the composite effect of many small concentric impact craters with rocky ejecta blankets. If this is the dominant mechanism for the production of other rays from Copernicus and other large lunar craters, then rays may not contain significant amounts of ejecta from the central crater or from large secondary craters. They may in fact only reflect local excavation of mare substrate material by myriads of small secondary or tertiary impact craters.


Excavation Substrate Material Dominant Mechanism Composite Effect Impact Crater 
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  1. Albee, A. L., Burnett, D. S., Chodos, A. A., Eugster, O. J., Huneke, J. C., Papanastassiou, D. A., Podosek, F. A., Russ, G. P. II, Sanz, H. G., Tera, F., and Wasserburg, G. J.: 1970, ‘Ages, Irradiation History, and Chemical Composition of Lunar Rocks from the Sea of Tranquillity’,Science 167, 463.Google Scholar
  2. Baldwin, R. B.: 1963,The Measure of the Moon, The Univ. of Chicago Press, Chicago, U.S.A.Google Scholar
  3. Greeley, R. and Gault, D. E.: 1970, ‘Precision Size-Frequency Distributions of Craters for 12 Selected Areas of the Lunar Surface’,The Moon, in press.Google Scholar
  4. Oberbeck, V. R. and Quaide, W. L.: 1968, ‘Genetic Implications of Lunar Regolith Thickness Variations’,Icarus 9, 446.Google Scholar
  5. Oberbeck, V. R.: 1970, ‘Lunar Dimple Craters’,Modern Geol. 1, 161.Google Scholar
  6. Quaide, W. L. and Oberbeck, V. R.: 1968, ‘Thickness Determinations of the Lunar Surface Layer from Lunar Impact Craters’,J. Geophys. Res. 73, 5247.Google Scholar
  7. Schmitt, H. H., Trask, N. J., and Shoemaker, E. M.: 1967, ‘Geologic Map of the Copernicus Quadrangle of the Moon’, inGeologic Atlas of the Moon, Copernicus Quadrangle 1-515 (LAC-58), Dept of the Interior, USGS.Google Scholar
  8. Shoemaker, E. M.: 1966, ‘Preliminary Analysis of the Fine Structure of the Lunar Surface in Mare Cognitum’, inThe Nature of the Lunar Surface (ed. by W. N. Hess, D. H. Menzel, and J. A. O'Keefe), The Johns Hopkins Press, Baltimore, Maryland.Google Scholar
  9. Shoemaker, E. M., Batson, R. M., Holt, H. E., Morris, E. C., Rennilson, J. J., and Whitaker, E. A.: 1967, ‘Television Observations from Surveyor III’, inSurveyor III Mission Report, Part II, Scientific Results, NASA Technical Report 32-1177, p. 9.Google Scholar
  10. Trask, N. J. and Rowan, L. C.: 1967, ‘Lunar Orbiter Photographs: Some Fundamental Observations’,Science 158, 1529.Google Scholar
  11. Van Diggelen, J.: 1969, ‘A Photometric Investigation of the Lunar Crater Rays’,The Moon 1, 67.Google Scholar
  12. Whitaker, E. A.: 1966, ‘The Surface of the Moon’ inThe Nature of the Lunar Surface (ed. by W. N. Hess, D. H. Menzel, and J. A. O'Keefe), The Johns Hopkins Press, Baltimore, Maryland.Google Scholar
  13. Wilhelms, D. E.: 1968, ‘Geologic Map of the Mare Vaporum Quadrangle of the Moon’ inGeologic Atlas of the Moon, Mare Vaporum Quadrangle 1-548 (LAC 59), Dept. of the Interior, USGS.Google Scholar

Copyright information

© D. Reidel Publishing Company 1971

Authors and Affiliations

  • Verne R. Oberbeck
    • 1
  1. 1.NASA Ames Research CenterMoffett FieldUSA

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