Initial Determinations of Ionospheric Electric Fields and Joule Heating from MAVEN Observations

Tuesday, 15 December 2015
Poster Hall (Moscone South)
Matthew O. Fillingim1, Alexander Lee Fogle1, Omar Aleryani1,2, P Dunn1, Robert J Lillis1, James P McFadden1, John E P Connerney3, Paul R Mahaffy3, Laila Andersson4 and Robert Ergun4, (1)University of California, Berkeley, Space Sciences Laboratory, Berkeley, CA, United States, (2)American University of Sharjah, University City, Sharjah, United Arab Emirates, (3)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (4)University of Colorado, Laboratory for Atmospheric and Space Physics, Boulder, CO, United States
MAVEN provides in-situ measurements of the neutral and ion species as well as the magnetic field throughout the ionosphere of Mars. By combining these measurements, we are able to calculate both the ionospheric currents and the ionospheric conductivity. It is then straightforward to determine the electric field in the collisional ionosphere from a simplified Ohm’s law. In addition, we can also estimate the amount of Joule heating in the ionosphere from j · E. Here, we show initial determinations of both ionospheric electric fields and Joule heating using MAVEN data. The electric fields are highly variable from orbit-to-orbit suggesting that the ionospheric electrodynamics can change on timescales of several hours. These changes may be driven by changes in the upstream solar wind and IMF or may result from dynamical variations of thermospheric neutral winds.