Thermospheric Density, Composition, and Temperature from GOES-R/SUVI Solar Occultations

A new dataset of atomic oxygen (O) and molecular nitrogen (N2) number density profiles, along with thermospheric temperature profiles between 180 and 500 km, has been developed. These profiles are derived from solar occultation measurements made by the Solar Ultraviolet Imager (SUVI) on the GOES-R satellites, using the 17.1, 19.5, and 30.4 nm channels. Discussed is the novel approach and methods for using EUV solar occultation images for measuring the thermospheric state. Measurement uncertainties are presented as a function of tangent altitude. At 250 km, number density uncertainties are found to be 7% and 14% for O and N2, respectively, and the uncertainty for neutral temperature at 250 km was found to be 2%. Total mass density comparisons with the NRLMSIS-2.0 model show good agreement at the dusk terminator, with an average difference of -2%, but larger discrepancies at dawn, with an average difference of -26%. These discrepancies are more prominent during quiet solar conditions, suggesting an overestimation of densities by MSIS during these conditions. Density comparisons with the IDEA-GRACE-FO and Dragster assimilative models show dawn/dusk percent differences of -24%/-2% and +2%/+13%, respectively. The dataset is available through the NOAA NCEI GOES-R L2 data pipeline for eclipse seasons from September 2018 onward and is expected to continue through 2035. As this measurement relies only on real-time NOAA space weather SUVI images, these density and temperature profiles could be produced in real-time, supporting critical space weather monitoring and prediction, filling in a current measurement gap of thermospheric temperature and density.