HR: 17:00h
AN: SA24A-05 [Abstracts]
TI: The Wind and Temperature Spectrometer (WTS) in the Atmospheric Neutral Density Experiment (ANDE)
Satellite
AU: * herrero, f
EM: fred.herrero@nasa.gov
AF: NASA Goddard Space Flight Center, Code 553, Greenbelt, MD 20771
United States
AU: Nicholas, A
AF: Naval Research Laboratory, Code 7607, Washington, DC 20375
United States
AU: Vancil, B
AF: e-beam, Inc, 21070 SW Tile Flat Rd, Beaverton, OR 97007
United States
AU: Aalami, D
EM: dean@spaceinstruments.com
AF: Space Instruments, Inc., 19 Hammond, Suite 508, Irvine, CA 92618-1636
United States
AU: Zaruba, C
AF: NASA Goddard Space Flight Center, Code 553, Greenbelt, MD 20771
United States
AU: Beasley, L
AF: NASA Goddard Space Flight Center, Code 553, Greenbelt, MD 20771
United States
AB:
Miniaturization efforts in new spectrometers for ionosphere/thermosphere investigations of the ion-drifts and neutral winds
and corresponding temperatures make possible very light (about 250 g) packages consuming less than 0.4 W. Previously
described, our approach measures the angular and energy distributions of neutral atoms and molecules (or ions) in two
perpendicular planes; using those distributions to determine the full wind vector, the temperature and the relative densities
of O and N2, as required for the ANDE mission. The measurements require two separate electron impact ion sources each with
its own electron beam cathode. We have developed a low-temperature thermionic emission cathode that delivers 1 mA electron
current at 80 mW power, making it possible to operate neutral wind/temperature experiments for the first time with powers
less than 0.5 W. Advances in the ion optics of the energy-angle spectrometer enhance the energy resolution-aperture product
more than a factor of 3 to enable energy resolutions of a few percent with large apertures. With these technology
improvements it is now possible to obtain the full neutral wind vector, temperature and O/N2 density ratio once per second in
a 250g/0.4W package with sensitivity up to about 500 km altitude in the thermosphere. We will describe the WTS as deployed
in ANDE and show simulated data with the non-linear least squares analysis to illustrate expected performance of the WTS in
the estimated errors in the three components of the wind, the temperature, and the relative densities.
DE: 7837 Neutral particles
DE: 7894 Instruments and techniques
DE: 2427 Ionosphere/atmosphere interactions (0335)
DE: 0355 Thermosphere--composition and chemistry
SC: SPA-Aeronomy [SA]
MN: 2004 AGU Fall Meeting