Hostname: page-component-76fb5796d-vvkck Total loading time: 0 Render date: 2024-04-26T03:00:13.841Z Has data issue: false hasContentIssue false
  • English
  • Français

The Magnetic Field of Mercury

Published online by Cambridge University Press:  30 March 2016

Norman F. Ness
Norman F. Ness*
Affiliation:
Laboratory for Extraterrestrial Physics, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The USA Mariner 10 spacecraft encountered Mercury three times in 1974-1975. The 1st and 3rd encounters provided detailed observations of a well developed, detached bow shock wave which results from the interaction of the solar wind. The planet possesses a global magnetic field, and modest magnetosphere, which deflects the solar wind. The field is approximately dipolar, with orientation in the same sense as Earth, tilted 12° from the rotation axis. The magnetic moment, 5×1022 Gauss-cm3, corresponds to an undistorted equatorial field intensity of 350γ, approximately 1% of Earth’s. The origin of the field, while unequivocally intrinsic to the planet, is uncertain. It may be due to remanent magnetization acquired from an extinct dynamo or a primordial magnetic field or due to a presently active dynamo. Among these possibilities, the latter appears more plausible at present. In any case, the existence of the magnetic field provides very strong evidence of a mature, differentiated planetary interior with a large core, Rc ≈ 0.7RM, and a record of the history of planetary formation in the magnetization of the crustal rocks.

Type
Joint Dicussions
Information
Highlights of Astronomy , Volume 4 , Issue 1: Highlights of Astronomy. As presented at the XVIth General Assembly of the IAU, 1976 (Part I) , 1977 , pp. 179 - 190
Copyright
Copyright © Reidel 1977

References

Armstrong, T.P., Krimigis, S.M. and Lanzerotti, L.J.: 1975, J. Geophys Res. 80, 4015.Google Scholar
Christon, S.P., Daly, S.F., Eraker, J. H., Perkins, M. A., Simpson, J. A. and Tuzzolino, A. J.: 1976, Trans. Am. Geophys. U., 57, 315.Google Scholar
Fairfield, D. H.: 1971, J. Geophys. Res. 76 6700.Google Scholar
Gubbins, D.: 1974, Revs. Geophys. Space Physics, 12, 137.CrossRefGoogle Scholar
Hartle, R. E., Ogilvie, K. W., Scudder, J. D., Bridge, S. H., Siscoe, G. L., Lazarus, A. J., Vasyliunas, V. M. and Yeates, C. M.: 1975, Nature, 255, 206.Google Scholar
Hill, T. W., Dessler, A. J. and Wolf, R. A.: 1976, (preprint).Google Scholar
Ness, N. F.: 1976, in Proceedings ISSTP, Boulder, CO. (in press).Google Scholar
Ness, N. F., Behannon, K. W., Lepping, R. P. and Schatten, K. W.: 1971, J. Geophys. Res. 76, 3564.Google Scholar
Ness, N. F., Behannon, K. W., Lepping, R. P., Whang, Y. C. and Schatten, K. H.: 1974a, Science, 183, 1301.CrossRefGoogle Scholar
Ness, N. F., Behannon, K. W., Lepping, R. P., Whang, Y. C. and Schatten, K. H.: 1974b, Science, 185, 151.Google Scholar
Ness, N. F., Behannon, K. W., Lepping, R. P. and Whang, Y. C.: 1975, J. Geophys. Res. 80, 2708.Google Scholar
Ness, N. F., Behannon, K. W., Lepping, R. P. and Whang, Y. C.: 1976, Icarus, 28 (in press).Google Scholar
Ness, N. F., and Thompson, R. F.: 1976, Trans. Am. Geophys. Un. 57, 315.Google Scholar
Neubauer, F. M.: 1975, J. Geophys. Res. 80, 3235.Google Scholar
Neubauer, F. M., and Schatten, K. H.: 1974, J. Geophys. Res. 79, 1550.Google Scholar
Ogilvie, K. W., Scudder, J. D., Hartle, R. E., Siscoe, G. S., Bridge, H. S., Lazarus, A. J., Asbridge, J. R., Bame, S. J. and Yeates, C. M.: 1974, Science, 185, 145.Google Scholar
Ogilvie, K. W., Scudder, J. D., Vasyliunas, V. M., Siscoe, G. L. and Hartle, R. E.: 1976, (preprint).Google Scholar
Siegfried, R. W., II, , and Solomon, S. C.: 1974, Icarus, 23, 192.Google Scholar
Simpson, J.A., Eraker, J.H., Lamport, J.E. and Walpole, P. H.: 1974, Science, 185, 160.Google Scholar
Simpson, J. A.: 1975, J. Geophys. Res. 80, 4018.Google Scholar
Siscoe, G. L., Ness, N. F., and Yeates, C. M.: 1975, J. Geophys. Res. 80 4359.Google Scholar
Solomon, S.: 1976, Icarus, 28 (in press).Google Scholar
Srnka, L.J.: 1976, EOS, Trans. AGU, 57, 271.Google Scholar
Stephenson, A. F.: 1976, Earth and PI. Sci. Letters, 28, 454.Google Scholar
Whang, Y.C.: 1976, J. Geophys. Res. (submitted).Google Scholar