Add to ORKGAccelerometer derived thermospheric density data from the LOGACS and SPADES satellites are processed to yield the equivalent density variation at 150 and 160 km respectively. Definite latitudinal and longitudinal variations are found which conflict with Jacchia's 1971 model. Time-latitude analyses are presented of density at a single altitude. The density response to a great geomagnetic storm is nearly the same from 250 S to 850 N except that a density trough forms just equatorward of the auroral oval. Gravity waves are observed during the storm. The structure and dynamics of the lower thermosphere are far more complex than previous studies indicate