Absence of an internal magnetic field at Callisto (original) (raw)

Nature volume 387, pages 262–264 (1997)Cite this article

Abstract

Little is known about the internal properties of Callisto—the outermost of Jupiter's four large galilean moons—other than the average density (about 1.8gem-3). The recent unexpected discovery1–4 that Ganymede, and perhaps Io, has an internally generated magnetic field, combined with gravity results5,6 suggesting that both Ganymede and Io are internally differentiated with metallic cores and rocky mantles, has heightened anticipation of the results obtained by the Galileo spacecraft in its recent fly-by of Callisto. Here we report that the spacecraft, passing the moon at a distance of only ∼1,100 km from the surface, detected only a small enhancement of the field strength (∼7nT), which maybe related to changes in the jovian plasma environment caused by Callisto7. Callisto does not have an internally generated magnetic field.

This is a preview of subscription content, access via your institution

Access options

Subscribe to this journal

Receive 51 print issues and online access

$199.00 per year

only $3.90 per issue

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Additional access options:

Similar content being viewed by others

References

  1. Kivelson, M. G. et al. A magnetic signature near Io: Initial report from the Galileo magnetometer. Science 273, 337–340 (1996).
    Article ADS CAS Google Scholar
  2. Kivelson, M. G. et al. Io's interaction with the plasma torus: Galileo magnetometer report. Science 274, 396–398 (1996).
    Article ADS CAS Google Scholar
  3. Kivelson, M. G. et al. Discovery of Ganymede's magnetic field by the Galileo spacecraft. Nature 384, 537–541 (1996).
    Article ADS CAS Google Scholar
  4. Gurnett, D. A., Kurth, W. S., Roux, A., Bolton, S. J. & Kennel, C. F. Evidence for a magnetosphere at Ganymede from plasma-wave observations by the Galileo spacecraft. Nature 384, 535–537 (1996).
    Article ADS CAS Google Scholar
  5. Anderson, J. D., Laux, E. L., Sjorgren, W. L., Schubert, G. & Moore, W. B. Gravitational constraints on the internal structure of Ganymede. Nature 384, 541–543 (1996).
    Article ADS CAS Google Scholar
  6. Schubert, G., Zhang, K., Kivelson, M. G. & Anderson, J. D. The magnetic field and internal structure of Ganymede. Nature 384, 544–545 (1996).
    Article ADS CAS Google Scholar
  7. Gurnett, D. A., Kurth, W. S., Roux, A. & Bolton, S. J. Absence of a magnetic-field signature in plasma-wave observations at Callisto. Nature 387, 261–262 (1997).
    Article ADS CAS Google Scholar
  8. Kivelson, M. G., Khurana, K. K., Means, J. D., Russell, C. T. & Snare, R. C. The Galileo magnetic field investigation. Space Sci. Rev 60, 357–383 (1992).
    Article ADS Google Scholar
  9. Belcher, J. W. in The Physics of the Jovian Magnetosphere 68–105 (Cambridge Univ. Press, 1983).
    Book Google Scholar
  10. Dessler, A. J. in The Physics of the Jovian Magnetosphere 498–504 (Cambridge Univ. Press, 1983).
    Google Scholar
  11. Vasyliunas, V. M. in The Physics of the Jovian Magnetosphere 395–453 (Cambridge Univ. Press, 1983).
    Book Google Scholar
  12. Barbosa, D. D. On the injection and scattering of protons in Jupiter's magnetosphere. J. Geophys. Res. 86, 8981–8990 (1981).
    Article ADS Google Scholar
  13. Frank, L. A. et al. Plasma observations at Io with the Galileo spacecraft. Science 274, 394–395 (1996).
    Article ADS CAS Google Scholar
  14. Neubauer, F. M. Nonlinear standing Alfvén wave current system at Io: Theory. J. Geophys. Res. 85, 1171 (1980).
    Article ADS Google Scholar
  15. Whang, Y. C. Interaction of a magnetized solar wind with the moon. Phys. Fluids 11, 969–975 (1968).
    Article ADS Google Scholar
  16. Colburn, D. S. et al. Diamagnetic solar wind cavity discovered behind the moon. Science 158, 1040–1042 (1967).
    Article ADS CAS Google Scholar
  17. Owen, C. J. et al. The lunar wake at 6.8 RL: WIND magnetic field observations. Geophys. Res. Lett. 23, 1263–1266 (1996).
    Article ADS Google Scholar
  18. Anderson, J. D., Lau, E. L., Sjogren, W. L., Schubert, G. & Moore, W. B. Gravitational evidence for an undifferentiated Callisto. Nature 387, 264–266 (1997).
    Article ADS CAS Google Scholar

Download references

Author information

Authors and Affiliations

  1. Institute of Geophysics and Planetary Physics, University of California, Los Angeles, California, 90095, USA
    K. K. Khurana, M. G. Kivelson, C. T. Russell & R. J. Walker
  2. Department of Earth and Space Sciences, University of California, Los Angeles, California, 90095, USA
    M. G. Kivelson & C. T. Russell
  3. Department of Physics, Imperial College of Science, Technology, and Medicine, London, SW7 2BZ, UK
    D. J. Southwood

Authors

  1. K. K. Khurana
    You can also search for this author inPubMed Google Scholar
  2. M. G. Kivelson
    You can also search for this author inPubMed Google Scholar
  3. C. T. Russell
    You can also search for this author inPubMed Google Scholar
  4. R. J. Walker
    You can also search for this author inPubMed Google Scholar
  5. D. J. Southwood
    You can also search for this author inPubMed Google Scholar

Rights and permissions

About this article

Cite this article

Khurana, K., Kivelson, M., Russell, C. et al. Absence of an internal magnetic field at Callisto.Nature 387, 262–264 (1997). https://doi.org/10.1038/387262a0

Download citation

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.