4.5 Article

Thermal Structure of the Middle and Upper Atmosphere of Mars From ACS/TGO CO2 Spectroscopy

Journal

JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
Volume 127, Issue 10, Pages -

Publisher

AMER GEOPHYSICAL UNION
DOI: 10.1029/2022JE007286

Keywords

Martian atmosphere; thermal structure; thermosphere; solar occultation; CO2 spectroscopy

Funding

  1. Russian Science Foundation [20-42-09035]
  2. UK Space Agency [ST/T002069/1]

Ask authors/readers for more resources

This paper reports the vertical profiling of carbon dioxide density and temperature in the upper Martian atmosphere using the Atmospheric Chemistry Suite (ACS) solar occultations onboard the ExoMars Trace Gas Orbiter. The study reveals the variability of different atmospheric layers and short-term fluctuations in the top layer related to dust activity.
Temperature and density in the upper Martian atmosphere, above similar to 100 km, are key diagnostic parameters to study processes of the species' escape, investigate the impact of solar activity, model the atmospheric circulation, and plan spacecraft descent or aerobraking maneuvers. In this paper, we report vertical profiling of carbon dioxide (CO2) density and temperature from the Atmospheric Chemistry Suite (ACS) solar occultations onboard the ExoMars Trace Gas Orbiter. A strong CO2 absorption band near 2.7 mu m observed by the middle infrared spectrometric channel (ACS MIR) allows the retrieval of the atmospheric thermal structure in an unprecedentedly large altitude range, from 20 to 180 km. We present the latitudinal and seasonal climatology of the thermal structure for 1.5 Martian years (MYs), from the middle of MY 34 to the end of MY 35. The results show the variability of distinct atmospheric layers, such as a mesopause (derived from 70 to 145 km) and homopause, changing from 90 to 100 km at aphelion to 120-130 km at perihelion. Some short-term homopause fluctuations are also observed depending on the dust activity.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.5
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available