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| Titel |
Concerning the Initial Temporal Evolution of a Hermean Feedback Dynamo |
| VerfasserIn |
D. Heyner, K.-H. Glassmeier, D. Schmitt, U. Motschmann, J. Wicht |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250021635
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| Zusammenfassung |
| Various possibilities are currently under discussion explaining the observed weakness of the
intrinsic magnetic field of planet Mercury. One of the possible dynamo scenarios is a dynamo
with feedback from the magnetosphere. Due to its weak planetary magnetic field,
Mercury exhibits a small magnetosphere whose sub-solar magnetopause distance
is only about 1.7 Hermean radii. Hence, the magnetic field due to magnetopause
currents cannot be disregarded in the dynamo region. Since the external field of
magnetospheric origin is antiparallel to the dipole component of the dynamo field, a negative
feedback results. For a simple αΩ - dynamo two stationary solutions of such a
feedback dynamo emerge, one with a weak and another with a strong magnetic field.
The question, however, is how these two stationary solutions can be realized. To
address this problem, we discuss various dynamic scenarios for simple dynamo
models and the conditions under which either of the stationary situations evolves. |
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