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Updated: Jun 16, 2026

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UV-Vis Spectroscopic Characterization of Nanomaterials in Aqueous Media
Published on: October 25, 2021
Mariner 6 and 7 ultraviolet spectrometers
Applied Optics
|January 23, 2010
Summary
Ultraviolet spectrometers captured Mars' upper atmosphere emission spectrum in 1969. The instruments successfully measured wavelengths from 1100-4300 A, providing valuable atmospheric data.
Area of Science:
- Planetary Science
- Atmospheric Science
- Spectroscopy
Background:
- Early space missions provided opportunities for in-situ atmospheric analysis.
- Understanding Mars' atmospheric composition is crucial for planetary evolution studies.
Purpose of the Study:
- To measure the ultraviolet emission spectrum of the Martian upper atmosphere.
- To assess the performance of specialized ultraviolet spectrometers in a planetary environment.
Main Methods:
- Utilized a planetary coronagraph and an Ebert-Fastie monochromator for ultraviolet observations.
- Employed photomultiplier tubes with cesium iodide and bialkali photocathodes to detect spectral ranges from 1100-4300 A.
- Calibrated instruments using a tungsten lamp, sodium salicylate screen, and nitric oxide cell.
Main Results:
- Successfully rejected off-axis light interference at distances up to 6600 km.
- Measured the emission spectrum of Mars' upper atmosphere at altitudes as low as 170 km.
- Acquired spectral data in the 1100-4300 A range.
Conclusions:
- The ultraviolet spectrometers were effective for Martian atmospheric analysis.
- The study provided early spectral data of Mars' upper atmosphere.
- Demonstrated the capability of instruments to operate and collect data in interplanetary space.
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