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Title: STELLAR WIND INFLUENCE ON PLANETARY DYNAMOS

Abstract

We examine the possible influence of early stellar wind conditions on the evolution of planetary dynamo action. In our model, the dynamo operates within a significant ambient magnetospheric magnetic field generated by the interaction between the stellar wind and the planetary magnetic field. This provides a negative feedback mechanism which quenches the dynamo growth. The external magnetic field magnitude which the dynamo experiences, and thus the strength of the quenching, depends on the stellar wind dynamic pressure. As this pressure significantly changes during stellar evolution, we argue that under early stellar system conditions the coupling between the stellar wind and the interior dynamics of a planet is much more important than has been thought up to now. We demonstrate the effects of the feedback coupling in the course of stellar evolution with a planet at a similar distance to the central star as Mercury is to the Sun.

Authors:
;  [1];  [2]
  1. Institut fuer Geophysik und extraterrestrische Physik, Technische Universitaet Braunschweig, Mendelssohnstrasse 3, D-38106 Braunschweig (Germany)
  2. Max-Planck-Institut fuer Sonnensystemforschung, Max-Planck-Strasse 2, D-37191 Katlenburg-Lindau (Germany)
Publication Date:
OSTI Identifier:
22034508
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 750; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTRONOMY; ASTROPHYSICS; COUPLING; DISTANCE; FEEDBACK; INTERACTIONS; MAGNETIC FIELDS; MERCURY PLANET; PLANETARY MAGNETOSPHERES; QUENCHING; STAR EVOLUTION; STELLAR WINDS; SUN

Citation Formats

Heyner, Daniel, Glassmeier, Karl-Heinz, and Schmitt, Dieter. STELLAR WIND INFLUENCE ON PLANETARY DYNAMOS. United States: N. p., 2012. Web. doi:10.1088/0004-637X/750/2/133.
Heyner, Daniel, Glassmeier, Karl-Heinz, & Schmitt, Dieter. STELLAR WIND INFLUENCE ON PLANETARY DYNAMOS. United States. doi:10.1088/0004-637X/750/2/133.
Heyner, Daniel, Glassmeier, Karl-Heinz, and Schmitt, Dieter. 2012. "STELLAR WIND INFLUENCE ON PLANETARY DYNAMOS". United States. doi:10.1088/0004-637X/750/2/133.
@article{osti_22034508,
title = {STELLAR WIND INFLUENCE ON PLANETARY DYNAMOS},
author = {Heyner, Daniel and Glassmeier, Karl-Heinz and Schmitt, Dieter},
abstractNote = {We examine the possible influence of early stellar wind conditions on the evolution of planetary dynamo action. In our model, the dynamo operates within a significant ambient magnetospheric magnetic field generated by the interaction between the stellar wind and the planetary magnetic field. This provides a negative feedback mechanism which quenches the dynamo growth. The external magnetic field magnitude which the dynamo experiences, and thus the strength of the quenching, depends on the stellar wind dynamic pressure. As this pressure significantly changes during stellar evolution, we argue that under early stellar system conditions the coupling between the stellar wind and the interior dynamics of a planet is much more important than has been thought up to now. We demonstrate the effects of the feedback coupling in the course of stellar evolution with a planet at a similar distance to the central star as Mercury is to the Sun.},
doi = {10.1088/0004-637X/750/2/133},
journal = {Astrophysical Journal},
number = 2,
volume = 750,
place = {United States},
year = 2012,
month = 5
}
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