Remote sensing of the nighttime ionosphere with the TIMED Global Ultraviolet Imager

The Global Ultraviolet Imager (GUVI) aboard the TIMED spacecraft monitors ultraviolet radiation from the terrestrial atmosphere in five spectral regions. Measurements of 1356-angstrom radiation on the Earth\textquoterights limb are part of this dataset. The primary source of this 1356-angstrom radiation on the night side is the recombination of molecular oxygen ions and electrons. In this work, we present a method for inferring vertical electron density profiles and total electron content (TEC) from the GUVI night-side limb data. We also describe the validation of these retrievals through the use of ground based measurements.