HR: 0800h
AN: SA21A-0342 [Abstracts]
TI: Remote sensing of O, N$_{2}$, and NO in the mesosphere and lower thermosphere using spatial heterodyne
spectroscopy
AU: * Stephan, A W
EM: andrew.stephan@nrl.navy.mil
AF: Naval Research Laboratory, E. O. Hulburt Center for Space Research,
4555 Overlook Ave. SW, Washington, DC 20375
United States
AU: Englert, C R
EM: englert@uap2.nrl.navy.mil
AF: Naval Research Laboratory, E. O. Hulburt Center for Space Research,
4555 Overlook Ave. SW, Washington, DC 20375
United States
AU: Cardon, J G
EM: cardon@uap2.nrl.navy.mil
AF: Naval Research Laboratory, E. O. Hulburt Center for Space Research,
4555 Overlook Ave. SW, Washington, DC 20375
United States
AU: Harlander, J M
EM: jmharlander@stcloudstate.edu
AF: St. Cloud State University, Department of Physics, Astronomy, and Engineering Science, St. Cloud, MN
56301
United States
AU: Roesler, F L
EM: roesler@wisp.physics.wisc.edu
AF: University of Wisconsin, Department of Physics,
1150 University Ave., Madison, WI 53706
United States
AB:
The composition and temperature of the mesosphere and lower
thermosphere can be obtained by inverting limb profiles
of middle UV airglow emissions near 214~nm and 247~nm.
At high altitudes (above 200 km), emissions related to O and
N$_{2}$ are prominent. Below 90~km, emissions from NO dominate the scene. In between these regions a merged spectrum of
emissions also represents an interaction point for physical processes between the mesosphere and thermosphere. However, the
overlap of these spectral features creates a hurdle to obtaining the high fidelity data needed to retrieve atmospheric
parameters. Uncertainties in emission sources are introduced when spectral features cannot be distinguished and modeling is
required to fit the data.
Spatial heterodyne spectroscopy (SHS) has the capability
of obtaining high spectral resolution (0.01~nm) measurements of these prominent middle UV emissions from the mesosphere and
lower thermosphere. This spectral resolution would eliminate much of the uncertainty inherent in fitting the emission
feature, thereby improving the accuracy of the emission profile. We present simulations from an SHS instrument being
investigated for development at the Naval Research Laboratory to make measurements at 214~nm and 247~nm. Instrument
requirements are derived from existing lower resolution spectra and profiles, the inversion of simulated data, and the
desired accuracy of the retrieved parameters. Our results show the enticing capability
for remote sensing of this under-explored region using SHS.
DE: 0310 Airglow and aurora
DE: 0355 Thermosphere--composition and chemistry
DE: 0394 Instruments and techniques
SC: SPA-Aeronomy [SA]
MN: 2004 AGU Fall Meeting