New Insights from Imaging the Earth's Inner Magnetosphere

James L. Green 


The Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) mission is the
first satellite mission that is dedicated to imaging the Earth's magnetosphere.
IMAGE utilizes the techniques of ultraviolet imaging, neutral atom imaging, and
radio plasma imaging to map out global distributions of the electron and proton
aurora; the helium ions of the plasmasphere; the ionospheric ion outflow; the
medium-energy ions of the near-Earth plasma sheet, ring current, and polar cusp;
the high-energy ions of the ring current and trapped radiation belts; and the
total plasma density from the ionosphere out to the magnetopause. Visuals from
IMAGE have provided a fascinating look at how plasma (ionized gas) circulates
within the magnetosphere geomagnetic storms. For instance, during less intense
geomagnetic storms a partial ring current of hot plasma is observed coming from
the Earth's magnetotail tail and venting out of the front of the magnetosphere
and into the solar wind rather than circulating around the Earth just outside
the plasmasphere as expected. The plasmasphere is constantly battered by inner
magnetospheric forces that peal off cold plasma, convect it sunward, and vent
it out the magnetopause on the dayside and into the solar wind. These surprising
views of the magnetosphere and others will be discussed. In addition, the future
for magnetospheric imaging also looks bright, when techniques such as tomography
and interferometry will be applied to new space missions in the solar wind, in
planetary magnetospheres, and moons of other planets.

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Goddard Space Flight Center Space Sciences Seminar
Wednesday, October 20, 3:00 pm, Johnson Center room 237