The Global UltraViolet Imager (GUVI) onboard NASA’s TIMED satellite performs extended scans across the earth’s disk and onto the limb, proving a wealth of valuable data on the atmosphere. ASTRA personnel have been involved with the GUVI project since its inception. We are focused on interpreting the column integrated O/N2 data from the dayside disk, together with the composition and temperature profiles on the limb. The figure shows as a function of altitude and latitude for single TIMED orbits: (a) thermospheric temperature; (b) atomic oxygen concentration; (c) molecular nitrogen concentration. ASTRA is using the TIME-GCM to interpret the GUVI data (Meier et al., 2005; Crowley et al., 2006).