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Updated: Jun 6, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Microwave spectroscopy of the Mars atmosphere
Applied Optics
|November 10, 2010
Summary
This study demonstrates millimeter-wavelength spectroscopy for Martian atmospheric analysis. It enables mapping water vapor and ozone, and measuring winds and temperature profiles for a comprehensive understanding of Mars
Area of Science:
- Planetary Science
- Atmospheric Science
- Spectroscopy
Background:
- The Martian atmosphere's composition and dynamics are crucial for understanding its evolution and potential habitability.
- Previous methods for atmospheric analysis have limitations regarding sensitivity and coverage.
Purpose of the Study:
- To investigate the utility of millimeter-wavelength spectral transitions for remote sensing of the Martian atmosphere.
- To assess the capability of a near-Mars orbiting spectrometer for detailed atmospheric profiling.
Main Methods:
- Utilizing a spectrometer (100-260 GHz) with a 30-50 cm telescope from a near-Mars orbit.
- Analyzing intense spectral lines of key molecules: H(2)O, CO, O(2), O(3), and H(2)O(2).
- Employing Doppler shifts for wind measurements and limb-sounding for temperature-pressure profiles.
Main Results:
- Successful mapping of water vapor (H(2)O) altitude and zonal distribution, even in dry conditions.
- All-planet ozone (O(3)) mapping, unaffected by lighting, dust, or clouds due to millimeter wave insensitivity to particles.
- Precise measurement of zonal and meridional winds (>10 km altitude) with ~3 m/s accuracy.
- Temperature-pressure profiles up to 100 km altitude determined using CO lines.
Conclusions:
- Millimeter-wavelength spectroscopy is a powerful tool for comprehensive Martian atmospheric remote sensing.
- This technique provides unprecedented capabilities for studying water cycle, photochemistry, and atmospheric dynamics on Mars.
- The proposed method offers robust and sensitive measurements for future Mars exploration missions.
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