  We test the utility of the OII 83.4 nm emission feature as a measure of
ionospheric parameters. Observed with the Remote Atmospheric and Ionospheric
Detection System (RAIDS) Extreme Ultraviolet Spectrograph on the International
Space Station (ISS), limb profiles of 83.4 nm emissions are compared to
predicted dayglow emission profiles from a theoretical model incorporating
ground-based electron density profiles measured by the Millstone Hill radar and
parameterized by a best-fit Chapman-{\alpha} function. Observations and models
are compared for periods of conjunction between Millstone Hill and the RAIDS
fields-of-view. These RAIDS observations show distinct differences in topside
morphology between two days, 15 January and 10 March 2010, closely matching the
forward model morphology and demonstrating that 83.4 nm emission is sensitive
to changes in the ionospheric density profile from the 340 km altitude of the
ISS during solar minimum. We find no significant difference between 83.4 nm
emission profiles modeled assuming a constant scale height Chapman-{\alpha}
best-fit to the ISR measurements and those assuming varying scale height.
