Encyclopedia of Astrobiology

Living Edition
| Editors: Muriel Gargaud, William M. Irvine, Ricardo Amils, Henderson James Cleaves, Daniele Pinti, José Cernicharo Quintanilla, Michel Viso

Magnetic Field, Planetary

Living reference work entry
DOI: https://doi.org/10.1007/978-3-642-27833-4_920-3

Definition

The magnetic field of a planet or satellite can be measured by magnetometers onboard orbiting space craft or – more locally – onboard landers and rovers. The magnetic field at any given point has a strength and a direction and thus is a vector field. On a global scale and measured at some distance from the planet or satellite, planetary magnetic fields resemble dipole fields. On or close to the surface the field is typically of more complicated topology. Planetary magnetic fields are generated by a dynamo mechanism in the iron-rich liquid core shells of terrestrial planets and satellites, in metallic hydrogen shells in Jupiter and Saturn, and in ionic oceans in Uranus and Neptune. Magnetic fields may be also induced in electrically conducting oceans in icy moons such as the Jovian moon Europa. Local magnetic fields may be caused by remnantly magnetized rock.

Overview

Magnetic fields are – in general – detected by the force they exert on magnetic materials and electrical...

Keywords

Core Dipole field Dynamo Induced magnetic field Magnetometer Remnant magnetic field 
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References and Further Reading

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  2. Baumjohann W, Nakamura R (2015) Magnetospheric contributions to the terrestrial magnetic field. In: Kono M, Schubert G (eds) Treatise on geophysics, 2nd ed, vol 5. Elsevier, Amsterdam, pp 79–90Google Scholar
  3. Connerney JEP (2015) Planetary magnetism. In: Spohn T, Schubert G (eds) Treatise on geophysics, 2nd ed, vol 10. Elsevier, Amsterdam, pp 195–237Google Scholar
  4. Hood LL, Vickery A (1984) Magnetic field amplification and generation in hypervelocity meteoroid impacts with application to lunar paleomagnetism. J Geophys Res 89:C211–C223CrossRefGoogle Scholar
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  9. Spohn T (2009) Magnetic fields. In: Trümper J (ed) Solar system, Landolt-Börnstein numerical data and functional relationships, vol VI/4B, New series. Springer, Berlin, pp 386–391Google Scholar
  10. Stevenson DJ (2003) Planetary magnetic fields. Earth Planet Sci Lett 208:1–11CrossRefADSGoogle Scholar
  11. Uno H, Johnson CL, Anderson BJ, Korth H, Solomon SC (2009) Modeling mercury’s internal magnetic field with smooth inversions. Earth Planet Sci Lett 285:328–339CrossRefADSGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Deutsches Zentrum für Luft- und Raumfahrt (DLR)Institut für PlanetenforschungBerlinGermany