Title: Retrieving Instantaneous Field of View and Geophysical Information for Atmospheric Limb Sounding with USGNC Near Real-Time Orbit Data,
Abstract: The Limb-imaging Ionospheric and Thermospheric Extreme-ultraviolet
Spectrograph (LITES) experiment is one of thirteen instruments aboard the Space
Test Program Houston 5 (STP-H5) payload on the International Space Station.
Along with the complementary GPS Radio Occultation and Ultraviolet Photometry
-- Colocated (GROUP-C) experiment, LITES will investigate ionospheric
structures and variability relevant to the global ionosphere. The ISS has an
orbital inclination of 51.6° which combined with its altitude of about 410
km enables middle- and low-latitude measurements from slightly above the peak
region of the ionosphere. The LITES instrument features a 10° by 10°
field of view which is collapsed horizontally, combining all information from a
given altitude. The instrument is installed such it looks in the wake of the
ISS and about 14.5° downwards in order to image altitudes ranging from
about 350 km to 150 km. The actual viewing altitude and geometry is directly
dependent on the pitch of the ISS, affecting the geophysical information
captured by the instrument.