대한토목학회논문집 (KSCE Journal of Civil and Environmental Engineering Research)

  • 제39권6호
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  • Pages.801-809
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  • 2019
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  • 1015-6348(pISSN)
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  • 2799-9629(eISSN)
대한토목학회 (Korean Society of Civil Engeneers)
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달 지하 얼음 층 존재 가능조건 검토를 위한 달 지반 온도 프로파일 산정 연구

A Study on the Lunar Ground Temperature Profile for Investigation of Possible Condition of the Ice Layer Existence in Sub-surface of the Moon

  • 고규현 (금오공과대학교 토목공학과) ;
  • 이장근 (한국건설기술연구원 미래융합연구본부) ;
  • 신휴성 (한국건설기술연구원 미래융합연구본부)
  • Go, Gyu-Hyun (Kumoh National Institute of Technology) ;
  • Lee, Jangguen (Korea Institute of Civil Engineering and Building Technology) ;
  • Shin, Hyu-Soung (Korea Institute of Civil Engineering and Building Technology)
  • 투고 : 2019.08.06
  • 심사 : 2019.11.04
  • 발행 : 2019.12.01
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초록

2009년 NASA에서 수행된 달 극지 탐사 미션을 통해 달 극지의 영구음영지역에 얼음 층이 존재한다는 증거가 발견되었다. 이후, 달 극지 지역 얼음 층 탐사를 위한 지반 특성 평가 연구들이 국내외적으로 활발히 이루어지고 있다. 본 연구에서는 달 영구음영지역의 지반온도변화를 예측하고, 얼음 층이 지반 온도 프로파일에 미치는 영향을 정량적으로 평가하고자 달 지반에 대한 비정상 상태 열 해석을 수행하였다. 수치해석결과를 통해 위도 86° 이상에서 달 지반 내부의 온도가 얼음승화 기준온도인 112 K 이하로 수렴한다는 것을 확인하였고, 이는 달 극지 내 얼음 층이 존재하고 있을 가능성이 높은 지역을 확률적으로 판단할 수 있는 근거가 되었다. 얼음 층이 매장되어 있는 깊이에 따라 지반 온도 프로파일에 미치는 영향정도가 다르게 나타났는데, 온도 편차가 큰 얕은 심도에 존재하는 얼음 층은 이질적인 온도분포 특성을 초래한다는 사실을 확인하였다. 또한, 본 연구는 매장된 얼음의 상을 보존하도록 하는 드릴 비트의 최대 허용 마찰열에 대해서 고찰하였다.

NASA's lunar polar exploration mission in 2009 confirmed the presence of ice-layer in the permanently shadowed regions (PSR) of the moon. Since then, studies have been actively conducted to evaluate the ground characteristics for exploring the ice-layer in the polar regions of the Moon. In this study, transient heat transfer analysis for the lunar ground was conducted to predict the ground's temperature that varies with the time and location. As a result of the numerical analysis, it was confirmed that the temperature under the lunar ground converged to below the ice sublimation reference temperature (≒112 K) at above 86° latitude. This model enabled us to identify the regions where there is a high possibility of ice being buried. Besides, we found that the ice-layer in the shallow region, where the temperature deviation is significant, makes ground temperature distribution heterogeneous. Lastly, this study suggested the maximum allowable frictional heat of a drill bit that can preserve the phase of buried ice.

키워드

참고문헌

  1. Bandfield, J. L., Hayne, P. O., Williams, J. P., Greenhagen, B. T. and Paige, D. A. (2015). "Lunar surface roughness derived from LRO Diviner radiometer observations." Icarus, Vol. 248, pp. 357-372. https://doi.org/10.1016/j.icarus.2014.11.009
  2. Carrier, W. D., Olhoeft, G. R. and Mendell, W. (1991). Physical properties of the lunar surface. In Lunar Sourcebook, New York: Cambridge University Press. pp. 475-594.
  3. Fa, W. and Wieczorek, M. A. (2012)."Regolith thickness over the lunar nearside: Results from Earth-based 70-cm Arecibo radar observations." Icarus, Vol. 218, No. 2, pp. 771-787. https://doi.org/10.1016/j.icarus.2012.01.010
  4. Hayne, P. O., Bandfield, J. L., Siegler, M. A., Vasavada, A .R., Ghent, R. R., Williams, J. P., Greenhagen, B. T., Aharonson, O., Elder, C. M., Lucey, P. G. and Paige, D. A. (2017). "Global regolith thermophysical properties of the moon from the diviner lunar radiometer experiment." J. Geophy. Res. Planets, Vol. 122, No. 12, pp. 2371-2400. https://doi.org/10.1002/2017JE005387
  5. Hayne, P., Bandfield, J., Vasavada, A., Ghent, R., Siegler, M., Williams, J. P., Greenhagen, B., Aharonson, O. and Paige, D. (2013). "Thermophysical properties of the lunar surface from Diviner observations." In EGU Gen. Assembly, Vol. 15, pp. 10871.
  6. Hemingway, B. S., Krupka, K. M. and Robie, R. A. (1981). "Heat capacities of the alkali feldspars between 350 and 1000 K from differential scanning calorimetry, the thermodynamic functions of the alkali feldspars from 298.15 to 1400 K, and the reaction quartz + jadeite = analbite." American Mineralogist, Vol. 66, pp. 1202-1215.
  7. Hermalyn, B., Schultz, P. H., Shirley, M., Ennico, K. and Colaprete, A. (2012). "Scouring the surface: Ejecta dynamics and the LCROSS impact event." Icarus, Vol. 218, No. 1, pp. 654-665. https://doi.org/10.1016/j.icarus.2011.12.025
  8. Hong, S. and Shin, H. (2018). "Trend analysis of lunar exploration missions for lunar base construction." J. Kor. Academia-Indust. cooper. Soci., Vol. 19, No. 7, pp. 144-152. https://doi.org/10.5762/KAIS.2018.19.7.144
  9. Ju, G. (2016). "Development status of domestic & overseas space exploration & associated technology." J. the Kor Soc. for aeronautical & space sci., Vol. 44, No. 8, pp. 741-757. https://doi.org/10.5139/JKSAS.2016.44.8.741
  10. Keihm, S. J. (1984). "Interpretation of the lunar microwave brightness temperature spectrum: Feasibility of orbital heat flow mapping." Icarus, Vol. 60, No. 3, pp. 568-589. https://doi.org/10.1016/0019-1035(84)90165-9
  11. Kopp, G. and Lean, J. L. (2011). "A new, lower value of total solar irradiance: Evidence and climate significance." Geophy. Res. Letters, Vol. 38, No. 1, p. L01706. https://doi.org/10.1029/2010GL045777
  12. Lang, K. (2012). Astrophysical data: Planets and stars. Springer, New York.
  13. Langseth, M. G., Keihm, S. J. and Peters, K. (1976). "Revised lunar heat-flow values, Lunar and Planet." Sci. Conf. Proc., Vol. 7, pp. 3143-3171.
  14. Ledlow, M. J., Zeilik, M., Burns, J. O., Gisler, G. R., Zhao, J. H. and Baker, D. N. (1992). "Subsurface emissions from Mercury-VLA radio observations at 2 and 6 centimeters." The Astrophy. J., Vol. 384, pp. 640-655. https://doi.org/10.1086/170906
  15. Lee, J., Ryu, B. H. and Lee, H. C. (2018) "Experimental assessment of frozen regolith shear strength using a newly developed drilling equipment" Proc. of KSCE 2018 Convention, KSCE, Korea.
  16. Logan, L. M., Hunt, G. R., Balsamo, S. R. and Salisbury, J. W. (1972). "Midinfrared emission spectra of Apollo 14 and 15 soils and remote compositional mapping of the moon." Lunar and Planet. Sci. Conf., Vol. 3, pp. 3069-3076.
  17. McKay, D. S., Heiken, G., Basu, A., Blanford, G., Simon, S., Reedy, R., French, B. M. and Papike, J. (1991). The lunar regolith. In Lunar sourcebook, Cambridge University Press, New York, pp. 285-356.
  18. Melosh, H. J. (1989). Impact cratering: A geologic process, Oxford University Press, New York, p. 245.
  19. Mitchell, D. L. and De Pater, I. (1994). "Microwave imaging of Mercury's thermal emission at wavelengths from 0.3 to 20.5 cm." Icarus, Vol. 110, No. 1, pp. 2-32. https://doi.org/10.1006/icar.1994.1105
  20. Spencer, J. R. (1990). "A Rough-Surface Thermophysical Model for Airless Planets." Icarus, Vol. 83, No. 1, pp. 27-38. https://doi.org/10.1016/0019-1035(90)90004-S
  21. Vasavada, A. R., Bandfield, J. L., Greenhagen, B. T., Hayne, P. O., Siegler, M. A., Williams, J. P. and Paige, D. A. (2012). "Lunar equatorial surface temperatures and regolith properties from the Diviner Lunar Radiometer Experiment." J. Geophy. Res., Vol. 117, No. E12, p. E00H18.
  22. Vasavada, A. R., Paige, D. A. and Wood, S. E. (1999). "Near-surface temperatures on Mercury and the Moon and the stability of polar ice deposits." Icarus, Vol. 141, No. 2, pp. 179-193. https://doi.org/10.1006/icar.1999.6175
  23. Whipple, F. L. (1950). "A comet model. I. The acceleration of comet Encke." The Astrophy. J., Vol. 111, pp. 375-394. https://doi.org/10.1086/145272
  24. Williams, J. P., Paige, D. A., Greenhagen, B. T. and Sefton-Nash, E. (2017). "The global surface temperatures of the moon as measured by the diviner lunar radiometer experiment." Icarus, Vol. 283, pp. 300-325. https://doi.org/10.1016/j.icarus.2016.08.012