HR: 0800h
AN: P21A-0225    [Abstracts]
TI: Development of a Hollow-Fiber Gas Correlation Radiometer for Column Measurements of Formaldehyde, Methane, and Water Vapor on Mars
AU: * Wilson, E L
EM: Emily.L.Wilson@nasa.gov
AF: NASA/GSFC, Laser & Electro-Optics Branch Code 554, Bldg. 19, Room N1, Greenbelt, MD 20771, United States
AU: Heaps, W S
EM: William.S.Heaps@nasa.gov
AF: NASA/GSFC, Instrument Systems and Technology Div. Code 550, Bldg. 19, Room S1, Greenbelt, MD 20771, United States
AU: Georgieva, E M
EM: egeorgieva@pop500.gsfc.nasa.gov
AF: UMBC/GSFC, Laser & Electro-Optics Branch Code 554, Bldg. T-19, Greenbelt, MD 20771, United States
AB: Development of a passive hollow-core fiber gas correlation radiometer instrument is presented for column absorption measurements of methane, formaldehyde and water vapor in the Martian atmosphere. This nadir viewing instrument consists of three sub-instruments for detecting CH4, H2CO, and H2O at 3.44 microns, 3.63 microns, and 3.12 microns respectively. At the core of each sub-instrument is a hollow-core optical fiber filled with a sample of the gas of interest which acts as a spectral filter. Gas correlation radiometers are a robust, reliable, highly developed technology. Adapting the newly available hollow-core optical fibers into this technology offers a substantial reduction in instrument mass and volume. This lightweight and compact instrument is highly suitable for deployment on a Mars orbiting mission. Performance of a Mars orbiting version of the hollow-core fiber instrument has been simulated assuming a 2 meter long, 500 micron inner diameter hollow-core fiber gas correlation cell, a 92.8 degree sun-synchronous orbit from 400 km with a horizontal sampling scale of 10 x 10 km2. Initial results indicate that for one second of averaging, a detection limit of 1 ppbv is possible for formaldehyde, with slightly better than 1 ppbv for methane. Because of its comprehensive measurement of both methane, formaldehyde, and water vapor at relevant detection limits and spatial scales, this instrument has the potential for localizing sources of these disequilibrium species on the Martian surface to aid in determining whether their origin is biogenic or geologic.
DE: 5200 PLANETARY SCIENCES: ASTROBIOLOGY
DE: 5400 PLANETARY SCIENCES: SOLID SURFACE PLANETS
DE: 5700 PLANETARY SCIENCES: FLUID PLANETS
DE: 6000 PLANETARY SCIENCES: COMETS AND SMALL BODIES
DE: 6200 PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS
SC: Planetary Sciences [P]
MN: 2007 Fall Meeting