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Two-hour Summary Plot
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This seven-panel plot shows the electron and magnetic field data as a
function of time in a two-hour window around periapsis.  The top two
panels show ER count rate at two energies (10 eV, 120 eV) as a
function of azimuth angle around the ER field of view.  The horizontal
stripe centered at 135 degrees is blockage caused by the high gain
antenna.

The next panel is an energy spectrum obtained by integrating over the
ER field of view at each of 30 energies from 10 eV to 20 keV.  Note
that there is a gap in the top three plots for a 20-minute window
around periapsis because the main analyzer is turned off to avoid
arcing in the Martian atmosphere.

The next panel is the magnetic field amplitude provided by Jack C.

The next panel shows the case current measured at the maximum positive
bias voltage, I(Vmax).  These measurements are obtained every six
seconds while the main analyzer is turned off, and once per packet
when the main analyzer is on.  Within the ionosphere, I(Vmax) is
roughly proportional to electron density (times the square root of the
electron temperature).  Outside the ionosphere, the case current is
dominated by photoelectrons, and thus provides a means to monitor
solar EUV flux.

The next panel shows case current measurements in a different format.
Here the I(V) curve is differentiated to show the electron energy
distribution.

The last panel shows the spacecraft altitude derived from the spk
kernels using MGAN.


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Twenty-minute Summary Plot
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This shows the magnetic field amplitude, I(Vmax), latitude, and
altitude during a 20-minute window around periapsis.  The ER high
voltage is off during this time, so some of the panels are not
available.  See the caption for the two-hour plots for more
information.