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Mars: Mariner 9 Spectroscopic Evidence for H2O Ice Clouds
Science (New York, N.Y.)
|October 26, 1973
Summary
Spectral analysis reveals water-ice clouds on Mars. Mariner 9 data indicates clouds composed of H(2)O ice particles with a 2.0 micrometer mean radius and a mass of 5 x 10(-5) grain/cm²
Area of Science:
- Planetary Science
- Spectroscopy
- Atmospheric Science
Background:
- Mariner 9 mission provided crucial data for Martian atmospheric studies.
- Understanding Martian clouds is key to deciphering the planet's climate and water cycle.
Purpose of the Study:
- To identify spectral features of Martian clouds using Mariner 9 data.
- To determine the physical properties of H(2)O ice clouds in the Tharsis Ridge region.
Main Methods:
- Analysis of spectral data from the Mariner 9 interferometer spectrometer.
- Comparison of observed spectra with theoretical radiative transfer models for ice clouds.
- Modeling variations in particle size distribution and integrated cloud mass.
Main Results:
- Observed spectral features were definitively identified as water-ice (H(2)O ice).
- The Tharsis Ridge H(2)O ice clouds consist of particles with a mean radius of approximately 2.0 micrometers.
- The integrated cloud mass was determined to be 5 x 10(-5) grain per square centimeter.
Conclusions:
- The presence and composition of water-ice clouds on Mars have been confirmed.
- The physical characteristics of these clouds provide insights into Martian atmospheric processes.
- This study refines our understanding of water distribution in the Martian atmosphere.
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