Low-temperature and low atmospheric pressure infrared reflectance spectroscopy of Mars soil analog materials

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

38

Analogs, Infrared Spectra, Low Pressure, Low Temperature, Mars Surface, Soils, Spectral Reflectance, Abundance, Mars Atmosphere, Samples, Spectroscopy, Spectrum Analysis, Water

Scientific paper

Infrared reflectance spectra of carefully selected Mars soil analog materials have been measured under low atmospheric pressures and temperatures. Chemically altered montmorillonites containing ferrihydrite and hydrated ferric sulfate complexes are examined, as well as synthetic ferrihydrate and a palagonitic soil from Haleakala, Maui. Reflectance spectra of these analog materials exhibit subtle visible to near-infrared features, which are indicative of nanophase ferric oxides or oxyhydroxides and are similar to features observed in the spectra of the bright regions of Mars. Infrared reflectance spectra of these analogs include hydration features due to structural OH, bound H2O and adsorbed H2O. The spectal character of these hydration features is highly dependent on the sample environment and on the nature of the H2O/OH in the analogs. The behavior of the hydration features near 1.9 micrometers, 2.2 micrometers, 2.7 micrometers, 3 micrometers, and 6 micrometers are reported here in spectra measured under Marslike atmospheric environment. In spectra of these analogs measured under dry Earth atmospheric conditions the 1.9-micrometer band depth is 8-17%; this band is much stonger under moist conditions. Under Marslike atmospheric conditions the 1.9-micrometer feature is broad and barely discernible (1-3% band depth) in spectra of the ferrihydrite and palagonitic soil samples. In comparable spectra of the ferric sulfate-bearing montmorillonite the 1.9-micrometer feature is also broad, but stronger (6% band depth). In the low atmospheric pressure and temperature spectra of the ferrihydrite-bearing montmorillonite this feature is sharper than the other analogs and relatively stronger (6% band depth). Although the intensity of the 3- micrometer band is weaker in spectra of each of the analogs when measured under Marslike conditions, the 3-micromter band remains a dominant feature and is especially broad in spectra of the ferrihydrite and palagonitic soil. The structural OH features observed in these materials at 2.2-2.3 micrometers and 2.27 micrometers remain largely unaffected by the environmental conditions. A shift in the Christiansen feature towards shorter wavelengths has also been observed with decreasing atmospheric pressure and temperature in the midinfrared spectra of these samples.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Low-temperature and low atmospheric pressure infrared reflectance spectroscopy of Mars soil analog materials does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Low-temperature and low atmospheric pressure infrared reflectance spectroscopy of Mars soil analog materials, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Low-temperature and low atmospheric pressure infrared reflectance spectroscopy of Mars soil analog materials will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-844972

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.