HR: 0830h
AN: SA41A-11    [Abstracts]
TI: Comparison of Thermospheric Density Derived From TIMED/GUVI Limb Observations with Total Mass Density Derived From Satellite Orbits
AU: * Emmert, J T
EM: jemmert@gmu.edu
AF: School of Computational Sciences, George Mason University 4400 University Dr, MSN 5C3, Fairfax, VA 22030 United States
AU: Meier, R R
EM: rmeier@gmu.edu
AF: School of Computational Sciences, George Mason University 4400 University Dr, MSN 5C3, Fairfax, VA 22030 United States
AU: Picone, J M
EM: picone@uap2.nrl.navy.mil
AF: E. O. Hulburt Center for Space Research, Naval Research Laboratory 4555 Overlook Ave SW, Washington, DC 20375 United States
AU: Lean, J L
EM: jlean@ssd5.nrl.navy.mil
AF: E. O. Hulburt Center for Space Research, Naval Research Laboratory 4555 Overlook Ave SW, Washington, DC 20375 United States
AB: We use TIMED/GUVI limb observations of thermospheric far UV dayglow to derive height profiles of O, N₂, and O₂ number densities. From these, we calculate the total mass density for comparison with total mass density derived from changes in the orbits of satellites with varying perigee heights. To accommodate sampling differences, we compare the ratio, averaged over ~3 days, of observed total mass density to that predicted by the NRLMSISE-00 empirical model. Our results represent the first validation of absolute densities derived from FUV limb scanning. The GUVI densities in the 300-500 km range are in good agreement with the orbit-derived densities, with both showing variations on solar rotation time scales. Of particular interest is a substantial depletion of upper thermospheric density around day 200 of 2002, when observed densities were 40% smaller than those predicted by NRLMSISE-00.
DE: 0355 Thermosphere--composition and chemistry
DE: 0394 Instruments and techniques
DE: 3360 Remote sensing
SC: SPA-Aeronomy [SA]
MN: 2005 Joint Assembly