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Solar wind forcing at Mercury: WSA‐ENLIL model results
Author(s) -
Baker Daniel N.,
Poh Gangkai,
Odstrcil Dusan,
Arge C. Nick,
Benna Mehdi,
Johnson Catherine L.,
Korth Haje,
Gershman Daniel J.,
Ho George C.,
McClintock William E.,
Cassidy Timothy A.,
Merkel Aimee,
Raines Jim M.,
Schriver David,
Slavin James A.,
Solomon Sean C.,
Trávníček Pavel M.,
Winslow Reka M.,
Zurbuchen Thomas H.
Publication year - 2013
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
eISSN - 2169-9402
pISSN - 2169-9380
DOI - 10.1029/2012ja018064
Subject(s) - magnetosphere , magnetopause , solar wind , physics , mercury's magnetic field , interplanetary magnetic field , polar wind , geophysics , computational physics , magnetic field , quantum mechanics
Analysis and interpretation of observations from the MESSENGER spacecraft in orbit about Mercury require knowledge of solar wind “forcing” parameters. We have utilized the Wang‐Sheeley‐Arge (WSA)‐ENLIL solar wind modeling tool in order to calculate the values of interplanetary magnetic field (IMF) strength ( B ), solar wind velocity ( V ) and density ( n ), ram pressure (~ nV 2 ), cross‐magnetosphere electric field ( V × B ), Alfvén Mach number ( M A ), and other derived quantities of relevance for solar wind‐magnetosphere interactions. We have compared upstream MESSENGER IMF and solar wind measurements to see how well the ENLIL model results compare. Such parameters as solar wind dynamic pressure are key for determining the Mercury magnetopause standoff distance, for example. We also use the relatively high‐time‐resolution B ‐field data from MESSENGER to estimate the strength of the product of the solar wind speed and southward IMF strength ( B s ) at Mercury. This product VB s is the electric field that drives many magnetospheric dynamical processes and can be compared with the occurrence of energetic particle bursts within the Mercury magnetosphere. This quantity also serves as input to the global magnetohydrodynamic and kinetic magnetosphere models that are being used to explore magnetospheric and exospheric processes at Mercury. Moreover, this modeling can help assess near‐real‐time magnetospheric behavior for MESSENGER or other mission analysis and/or ground‐based observational campaigns. We demonstrate that this solar wind forcing tool is a crucial step toward bringing heliospheric science expertise to bear on planetary exploration programs.