Search Publications
Global Distribution and Seasonality of Martian Atmospheric HCl Explained Through Heterogeneous Chemistry
Trokhimovskiy, Alexander; Korablev, Oleg; Olsen, Kevin S. +4 more
Recent observations from the ExoMars Trace Gas Orbiter (TGO) have revealed the presence of hydrogen chloride (HCl) in the martian atmosphere. HCl shows strong seasonality, primarily appearing during Mars' perihelion period before decreasing faster than projected from photolysis and gas-phase chemistry. HCl profiles also display local anti-correlat…
A Case Study on the Impact of Interplanetary Coronal Mass Ejection on the Martian O(1S) 557.7 nm Dayglow Emission Using ExoMars TGO/NOMAD-UVIS Observations: First Results
Vandaele, Ann Carine; Gérard, Jean-Claude; Thomas, Ian R. +6 more
We report, for the first time, the impact of interplanetary coronal mass ejections (ICME) on the recently discovered O(1S) 557.7 nm dayglow emission in the Martian atmosphere. While there are a few studies on the seasonal variation of 557.7 nm dayglow emission available in the literature, the impact of ICME has not been investigated so …
Strong Localized Pumping of Water Vapor to High Altitudes on Mars During the Perihelion Season
Aoki, S.; Vandaele, A. C.; Daerden, F. +18 more
Here we present water vapor vertical profiles observed with the ExoMars Trace Gas Orbiter/Nadir and Occultation for MArs Discovery instrument during the perihelion and Southern summer solstice season (LS = 240°-300°) in three consecutive Martian Years 34, 35, and 36. We show the detailed latitudinal distribution of H2O at tan…
Repeated and Long-Lasting Fault Activation on Amazonian Mars as Demonstrated by Tectonically Induced Landslides
Fawdon, P.; Balme, M. R.; Rothery, D. A. +1 more
We identify and analyze a large shortening structure (surface expression of a thrust fault) in western Arabia Terra, Mars, exhibiting recent, repeated, and long-lasting tectonic activity. Where the fault system deforms Marsabit crater rim, four landslides with differing degradation states extend onto the crater floor. We propose these were trigger…
Quantification of Carbonates, Oxychlorines, and Chlorine Generated by Heterogeneous Electrochemistry Induced by Martian Dust Activity
Olsen, Kevin S.; Wang, Alian; Jackson, Andrew W. +4 more
Heterogeneous electrochemistry induced by Martian dust activity is an important type of atmosphere-surface interaction that affects geochemical processes at the Martian surface and in the Martian atmosphere. We have experimentally demonstrated that heterogeneous electrochemistry stimulated by mid-strength dust events can decompose common chloride …
The Deuterium Isotopic Ratio of Water Released From the Martian Caps as Measured With TGO/NOMAD
Vandaele, Ann Carine; Brines, Adrian; Aoki, Shohei +18 more
We report vertical profiles of water and D/H for one Martian year as measured with the TGO/NOMAD instrument. The observations were performed via solar occultation, providing water profiles up to ∼100 km and D/H up to ∼60 km, with a vertical resolution of 1-2 km. The measurements reveal dramatic variability of water and D/H over short timescales an…
Thermal Tides in the Martian Atmosphere Near Northern Summer Solstice Observed by ACS/TIRVIM Onboard TGO
Montmessin, Franck; Trokhimovskiy, Alexander; Korablev, Oleg +8 more
Thermal tides in the Martian atmosphere are analyzed using temperature profiles retrieved from nadir observations obtained by the TIRVIM Fourier-spectrometer, part of the Atmospheric Chemistry Suite onboard the ExoMars Trace Gas Orbiter. The data is selected near the northern summer solstice at solar longitude (LS) 75°-105° of Martian Y…
Planet-Wide Ozone Destruction in the Middle Atmosphere on Mars During Global Dust Storm
Aoki, S.; Vandaele, A. C.; Daerden, F. +22 more
The Nadir and Occultation for MArs Discovery (NOMAD)/UV-visible (UVIS) spectrometer on the ExoMars Trace Gas Orbiter provided observations of ozone (O3) and water vapor in the global dust storm of 2018. Here we show in detail, using advanced data filtering and chemical modeling, how Martian O3 in the middle atmosphere was des…
Variations in Vertical CO/CO2 Profiles in the Martian Mesosphere and Lower Thermosphere Measured by the ExoMars TGO/NOMAD: Implications of Variations in Eddy Diffusion Coefficient
Vandaele, Ann Carine; Modak, Ashimananda; Brines, Adrian +19 more
Using the Nadir and Occultation for MArs Discovery instrument aboard Trace Gas Orbiter, we derived the CO/CO2 profiles between 75 and 105 km altitude with the equivalent width technique. The derived CO/CO2 profiles showed significant seasonal variations in the southern hemisphere with decreases near perihelion and increases n…
Revealing a High Water Abundance in the Upper Mesosphere of Mars With ACS Onboard TGO
Montmessin, Franck; Belyaev, Denis A.; Fedorova, Anna A. +7 more
We present the first water vapor profiles encompassing the upper mesosphere of Mars, 100-120 km, far exceeding the maximum altitudes where remote sensing has been able to observe water to date. Our results are based on solar occultation measurements by Atmospheric Chemistry Suite (ACS) onboard the ExoMars Trace Gas Orbiter (TGO). The observed wave…