PS4.5
Mars Science and Exploration

PS4.5

EDI
Mars Science and Exploration
Convener: Benjamin Bultel | Co-conveners: Agata Krzesinska, Arianna Piccialli, Jessica Flahaut, Xiao Long
Presentations
| Tue, 24 May, 10:20–11:49 (CEST), 13:20–18:17 (CEST)
 
Room 1.85/86

Presentations: Tue, 24 May | Room 1.85/86

Chairpersons: Ricardo Hueso, Lori Neary
10:20–10:22
10:22–10:27
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EGU22-7939
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ECS
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Virtual presentation
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Danny McCulloch, Nathan Mayne, Matthew Bate, and Denis Sergeev

Mars climate modelling is essential for understanding the atmosphere of a planet with limited in-situ observations. Such research is crucial if humanity will ever hope to explore the red planet in the coming decades. There are already Global Climate Models (hereafter; GCMs) for Mars that are tackling this challenge, but there are still processes that are poorly understood or difficult to simulate, such as inter-annual dust storms or a dynamically-calculated CO2 ice cycle which affects global pressure changes. In order to address these issues in current Mars modelling, we propose a GCM capable of reproducing similar results by using different parameterisation. This multi-faceted approach would be pivotal in tackling the aforementioned issues, in addition to providing validation of modelling techniques in extreme conditions. 

We adapt a highly-sophisticated and modular GCM, the Met Office Unified Model, currently routinely employed for weather and climate prediction on Earth, to the present climate of Mars. We detail the key climate processes driving Mars' atmosphere and how we characterise them, namely:

  • Dust
  • Orography
  • Orbital parameters
  • Atmospheric composition and pressure
  • Atmospheric H2O
  • CO2 ice

By incrementally adapting schemes already established and used extensively for Earth simulations, we can reproduce a comprehensive and complex climate model of Mars, whilst simultaneously assessing the significance of each process. To verify our model, we compare our GCM against in-situ data from the Viking landers and outputs from the LMD Mars GCM. Through this, we demonstrate how we are able to reproduce key processes in the Martian atmosphere across its seasons, between which conditions can vary greatly. We then speculate what processes still need implementation or refinement and the impact they may have on our current outputs. 

We will finish by detailing the remaining schemes to be implemented and how they might impact the output of our GCM, namely; a CO2 ice scheme and atmospheric moisture. The implementation of these processes will further increase the validity and accuracy of our results. Potential future work would include investigating diurnal fluctuations or inter-annual phenomena. Our GCM and modelling methods would eventually aim to expand the capabilities of the wider Mars-modelling community, the benefits of which, will bring us closer to unlocking and understanding the intricacies of Mars' unique environment.

How to cite: McCulloch, D., Mayne, N., Bate, M., and Sergeev, D.: Adapting an Earth Global Climate Model for a Modern-day Martian climate., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7939, https://doi.org/10.5194/egusphere-egu22-7939, 2022.

10:27–10:32
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EGU22-3635
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ECS
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Presentation form not yet defined
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Romain Vandemeulebrouck, Francois Forget, Lucas Lange, Ehouarn Millour, Antony Delavois, Antoine Bierjon, Joseph Naar, and Aymeric Spiga

To accurately simulate the climate and the fate of volatiles for thousands to millions of years we must couple physical processes with very different timescale, ranging from clouds microphysics and atmospheric dynamics (represented in the GCM) to the evolution of lakes, glacier accumulation, and subsurface ice evolution.

Given the diversity and the complexity of the Martian paleoclimates, we choose to use use an ambitious “asynchronous coupling” between the slow ice and water reservoirs models and the GCM.

In practice our innovative Mars evolution model will use a horizontal grid identical to that of the GCM, and include the same representation of the micro-climate on slopes. In our case, we will run the Mars Evolution Model with a timestep of 50 to ~500 years, depending upon the dynamics of the modeled system (smaller timesteps must first be used so that the different volatile reservoirs reach a quasi-equilibrium, then the timestep will depends on the evolution of the forcing, which is slow in the case of obliquity, for instance) . At each timestep, the inputs from the atmosphere (e.g. mean precipitation, sublimation and evaporation, temperatures, dust deposition) will be obtained through a multi-annual run of the Global Climate model using the outcome of the Mars Evolution Model as initial state.

First results about evolution of water ice and CO2 ice glacier will be presented.

How to cite: Vandemeulebrouck, R., Forget, F., Lange, L., Millour, E., Delavois, A., Bierjon, A., Naar, J., and Spiga, A.: Simulating long term climate variation with a planetary evolution model, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3635, https://doi.org/10.5194/egusphere-egu22-3635, 2022.

10:32–10:37
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EGU22-3651
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ECS
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Presentation form not yet defined
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Lucas Lange, François Forget, Romain Vandemeulebrouck, Ehouarn Millour, Antony Delavois, Joseph Naar, Aymeric Spiga, Antoine Bierjon, and Etienne Dupont

In some high latitude craters, intriguing moraines are interpreted to have been deposited by CO2 ice glaciers, essentially frozen from when the local climate was colder (i.e., when Mars obliquity was low) [1]. This scenario has been little studied, but it suggests that the atmosphere could totally collapse into CO2  glaciers, leaving behind a residual atmosphere of only Ar and N2, but 20 times less dense than today [2]. 

However, these results are based on a radiative equilibrium that does not take into account all the dynamics of the atmosphere.  Such periods of low obliquities generally last tens of thousands of years [3], making a complete simulation with a classical Global Circulation Model impossible.  

We will present the preliminary results of our climate simulations of Mars at low obliquity based on our new tool which is the Planetary Evolution Model developed at the LMD (Fig 1.). This model allows us to simulate the evolution of the climate, based on the LMD GCM, over long-time steps. Particular attention will be paid to the condensation of the atmosphere in the form of CO2  glaciers, and to the composition of the residual atmosphere.

Fig 1. Principles of the Planetary Evolution Model 

References: 
[1] Kreslavsky and Head, Carbon dioxide glaciers on Mars: Products of recent low obliquity epochs(?). Icarus, 216:111–115, 2011.
[2] Kreslavsky and Head. Mars at very low obliquity: Atmospheric collapse and the fate of volatiles. Geophysical Research Letters, 32(L12202), 2005.

[3] Laskar, Correia, Gastineau, Joutel, Levrard, Robutel, Long term evolution and chaotic diffusion of the insolation quantities of Mars. Icarus 170, 343–364, 2004.

Acknowledgments:
This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No 835275).

How to cite: Lange, L., Forget, F., Vandemeulebrouck, R., Millour, E., Delavois, A., Naar, J., Spiga, A., Bierjon, A., and Dupont, E.: Climate Simulations of Mars at Low Obliquity, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3651, https://doi.org/10.5194/egusphere-egu22-3651, 2022.

10:37–10:42
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EGU22-4517
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ECS
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Presentation form not yet defined
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Antony Delavois, François Forget, Martin Turbet, Ehouarn Millour, Romain Vandemeulebrouck, Lucas Lange, and Antoine Bierjon

Through today's observation of dry lakes, rives and large valley networks, we can assume liquid water abundantly flowed on Mars during the Noachian era, approximatively 4Gya. However, the climate that host this active water cycle is yet poorly understood. Recent modeling studies tried to reproduce the conditions that may have occured on the planet, trying to find an atmospheric process or composition that could solve the well known Faint Young Sun Paradox. Theses modeling studies, through the use of 3-dimensional Global Climate Models struggled to warm sufficiently the past climate of Mars, even considering different greenhouse gases, the role of clouds, meteoritic impact or even volcanism. However, the presence of H2 could be an interesting solution for a sustainable warming as some recent studies suggest (Turbet and Forget, 2021). Another recent study (Ito et al. 2020) suggested that H2O2 might be a convincing candidate but has to be in high supersaturation ratio in the atmosphere, even though it only used a simplified 1D model and relatively high supersaturation levels.

We try here to explore the scenario of supersaturated water, that might be a specy able to provide a sufficient global warming under supersaturated conditions or through the formation of high altitude clouds.  Through 1D and 3D modeling, we try to constrain the theoritical supersaturation level of H2O that will allow the warming of the climate above 273K. Our results suggest that in an atmosphere only composed of CO2 and H2O, water supersaturation can create a significant warming but only with with supersaturation levels in the lower layers of the atmosphere, although it can be seen as unrealistic. We describe in this work the effect of supersaturation on temperatures, clouds, and the water cycle of the simulated planet. Even if we do not tackle the question whether the supersaturation hypothesis is realistic or not, these results give a better understanding of what would be Early Mars' climate under such conditions.

How to cite: Delavois, A., Forget, F., Turbet, M., Millour, E., Vandemeulebrouck, R., Lange, L., and Bierjon, A.: Water supersaturation modeling for Early Mars Climate during Noachian, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-4517, https://doi.org/10.5194/egusphere-egu22-4517, 2022.

10:42–10:47
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EGU22-679
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On-site presentation
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Lonneke Roelofs, Susan Conway, Matthew Sylvest, Manish Patel, Jim McElwaine, Maarten Kleinhans, and Tjalling de Haas

Martian gullies are alcove-channel-fan systems that have been hypothesized to be formed by the action of liquid water and brines, the effects of sublimating CO2 ice, or a combination of these processes. Recent activity and new flow deposits in these systems have shifted the leading hypothesis from water-based flows to CO2-driven flows, as it is hard to reconcile present activity with the low availability of atmospheric water under present Martian conditions. Direct observations of flows driven by metastable CO2 on the surface of Mars are however nonexistent, and our knowledge of CO2-driven flows under Martian conditions remains limited. For the first time, we produced CO2-driven granular flows in a small-scale flume under Martian atmospheric conditions in the Mars Chamber at the Open University (UK). The experiments were used to quantify the slope threshold and CO2 fraction limits for fluidization. With these experiments, we show that the sublimation of CO2 can fluidize sediment and sustain granular flows under Martian atmospheric conditions, and even transport sediment with grain sizes equal to half the flow depth. The morphology of the deposits is lobate and depends highly on the CO2-sediment ratio, sediment grain size, and flume angle. The gas-driven granular flows are sustained under low (<20º) flume angles and small volumes of CO2 (around 5% of the entire flow). Pilot experiments with sediment flowing over a layer of CO2 suggest that even smaller percentages of CO2 ice are needed for fluidization. The data further shows that the flow dynamics are complex with surging behavior and complex pressure distribution in the flow, through time and space.

How to cite: Roelofs, L., Conway, S., Sylvest, M., Patel, M., McElwaine, J., Kleinhans, M., and de Haas, T.: Experimental CO2-driven granular flows under Martian atmospheric conditions, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-679, https://doi.org/10.5194/egusphere-egu22-679, 2022.

10:47–10:52
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EGU22-13045
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Virtual presentation
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Tariq Majeed, Hessa AlSuwaidi, Stephen W. Bougher, and Achim Morschhauser

The northern hemispheric electron density (Ne) data acquired by the Radio Occultation Science Experiments (ROSE) onboard the Mars Atmosphere and Volatile Evolution (MAVEN) have indicated more complicated ionospheric structure of Mars than previously thought.  Large variations in the topside Ne scale heights are observed presumably in response to the outward flow of the ionospheric plasma or changes in plasma temperatures.   We use our 1-D chemical diffusive model coupled with the Mars - Global Ionosphere Thermosphere Model (M-GITM) to interpret the northern upper ionospheric structure at Mars.  The primary source of ionization in the model is due to solar EUV radiation. Our model is a coupled finite difference primitive equation model which solves for plasma densities and vertical ion fluxes.  The photochemical equilibrium for each ion is assumed at the lower boundary of the model, while the flux boundary condition is assumed at the upper boundary to simulate plasma loss from the Martian ionosphere.  The crustal magnetic field at the measured Ne locations is weak and mainly horizontal and does not allow plasma to move vertically.   Thus, the primary plasma loss from the topside ionosphere at these locations is most likely caused by diverging horizontal fluxes of ions, indicating that the plasma flow in the upper ionosphere of Mars is controlled by the solar wind dynamic pressure.  We find that the variation in the topside Ne scale heights is sensitive to magnitudes of upward ion fluxes derived from ion velocities that we impose at the upper boundary to explain the topside ionospheric structure.  The model requires upward velocities ranging from 50 ms-1 to 90 ms-1 for all ions to ensure an agreement with the measured Ne profiles. The corresponding outward fluxes in the range 1.1 x 10– 5.8 x 106 cm-2 s-1 are calculated for O2+ compared to those for O+ in the range 3.8 x 105 – 6.7 x 105 cm-2 s-1.  The model results for the northern Ne profiles will be presented in comparison with the measured Ne profiles.  

How to cite: Majeed, T., AlSuwaidi, H., Bougher, S. W., and Morschhauser, A.: A Model Analysis of the Northern Ionospheric Structure Observed with the MAVEN/ROSE at Mars, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-13045, https://doi.org/10.5194/egusphere-egu22-13045, 2022.

10:52–10:57
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EGU22-13204
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ECS
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Virtual presentation
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Camila Cesar, Antoine Pommerol, Nicolas Thomas, Ganna Portyankina, and Candice J. Hansen

Orbital data from the Colour and Stereo Surface Imaging System (CaSSIS) onboard the ExoMars Trace Gas Orbiter showed interesting images of the circumpolar areas during spring. The winter-formed dusty CO2 ice cap goes under self-cleaning processes producing a translucent slab. With grazing spring sunlight, it starts to sublimate at the base and from overpressure, cold jets erupt leaving erosion marks in the underlying substrate and dust/sand deposits at the surface. This model, proposed by Kieffer, is commonly accepted to explain dark spots and fans deposits as well as spiders.

To test different aspects of this model, we combine observational data from CaSSIS with experimental work for which Martian temperature and pressure at high latitudes could be reached in a simulation chamber. Preliminary results on sinking analogous dust material (MGS-1) on a CO2 ice slab have been promising. We aim to quantify in better details the sinking ratio, colour variations and frost (H2O and/or CO2) depositions on CO2/MGS-1 samples under various setup conditions (illumination, material distribution). Using a hyperspectral device, we can measure the reflectance and simulate the CaSSIS signal in the different filters (PAN, NIR, RED, BLU) to compare to actual images that have been acquired during southern spring. 

How to cite: Cesar, C., Pommerol, A., Thomas, N., Portyankina, G., and Hansen, C. J.: Laboratory simulations of Martian Southern Spring : the outcome of CO2 cold jets, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-13204, https://doi.org/10.5194/egusphere-egu22-13204, 2022.

10:57–11:02
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EGU22-12125
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Virtual presentation
Arianna Piccialli, Ann Carine Vandaele, Lori Neary, Yannick Willame, Shohei Aoki, Loic Trompet, Cedric Depiesse, Sebastian Viscardy, Frank Daerden, Justin Erwin, Ian R. Thomas, Bojan Ristic, Jon P. Mason, Manish Patel, Alain Khayat, Mike Wolff, Giancarlo Bellucci, and Jose Juan Lopez-Moreno

We will investigate the impact of day-night temperature and compositional gradients at the Martian terminator on the retrieval of vertical profiles of ozone obtained from NOMAD-UVIS solar occultations

Rapid variations in species concentration at the terminator have the potential to cause asymmetries in the species distributions along the line of sight of a solar occultation experiment. Ozone, in particular, displays steep gradients across the terminator of Mars due to photolysis [1]. Nowadays, most of the retrieval algorithms for solar and stellar occultations rely on the assumption of a spherically symmetrical atmosphere. However, photo-chemically induced variations near sunrise/sunset conditions need to be taken into account in the retrieval process in order to prevent inaccuracies.

NOMAD (Nadir and Occultation for MArs Discovery) is a spectrometer composed of 3 channels: 1) a solar occultation channel (SO) operating in the infrared (2.3-4.3 μm); 2) a second infrared channel LNO (2.3-3.8 μm) capable of doing nadir, as well as solar occultation and limb; and 3) an ultraviolet/visible channel UVIS (200-650 nm) that can work in the three observation modes [2,3]. 

The UVIS channel has a spectral resolution <1.5 nm. In the solar occultation mode, it is mainly devoted to study the climatology of ozone and aerosols [4,5,6].

Since the beginning of operations, on 21 April 2018, NOMAD-UVIS acquired more than 8000 solar occultations with an almost complete coverage of the planet.

NOMAD-UVIS spectra are simulated using the line-by-line radiative transfer code ASIMUT-ALVL developed at IASB-BIRA [7]. In a preliminary study based on SPICAM-UV solar occultations (see [8]), ASIMUT was modified to take into account the atmospheric composition and structure at the day-night terminator. As input for ASIMUT, we used gradients predicted by the 3D GEM-Mars v4 Global Circulation Model (GCM) [9,10]. 

References
[1] Lefèvre, F., Bertaux, J.L., Clancy, R. T., Encrenaz, T., Fast, K., Forget, F., Lebonnois, S., Montmessin, F., Perrier, S., Aug. 2008. Heterogeneous chemistry in the atmosphere of Mars. Nature 454, 971–975.
[2] Vandaele, A.C., et al., Planetary and Space Science, Vol. 119, pp. 233–249, 2015. 
[3] Neefs, E., et al., Applied Optics, Vol. 54 (28), pp. 8494-8520, 2015.
[4] M.R. Patel et al., In: Appl. Opt. 56.10 (2017), pp. 2771–2782. DOI: 10.1364/AO.56.002771. 
[5] M.R. Patel et al., In: JGR (Planets), Vol. 126, Is. 11, 2021.
[6] Khayat, Alain S. J., et al., In: JGR (Planets), Vol. 126, Is. 11, 2021.
[7] Vandaele, A.C., et al., JGR, 2008. 113 doi:10.1029/2008JE003140.
[8] Piccialli, A., Icarus, submitted.
[9] Neary, L., and F. Daerden (2018), Icarus, 300, 458–476, doi:10.1016/j.icarus.2017.09.028.
[10] Daerden et al., 2019, Icarus 326, https://doi.org/10.1016/j.icarus.2019.02.030

How to cite: Piccialli, A., Vandaele, A. C., Neary, L., Willame, Y., Aoki, S., Trompet, L., Depiesse, C., Viscardy, S., Daerden, F., Erwin, J., Thomas, I. R., Ristic, B., Mason, J. P., Patel, M., Khayat, A., Wolff, M., Bellucci, G., and Lopez-Moreno, J. J.: Impact of gradients at the Martian terminator on the retrieval of ozone from TGO/NOMAD-UVIS, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12125, https://doi.org/10.5194/egusphere-egu22-12125, 2022.

11:02–11:07
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EGU22-1114
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ECS
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Virtual presentation
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Aurélien Stcherbinine, Franck Montmessin, Mathieu Vincendon, Michael Wolff, Oleg Korablev, Anna Fedorova, Alexander Trokhimovskiy, Gaetan Lacombe, Lucio Baggio, Abdenour Irbah, and Ashwin Braude

The Atmospheric Chemistry Suite (ACS) MIR channel onboard the ESA-Roscosmos Trace Gas Orbiter (TGO) (Korablev et al., 2018, 2019) probes the Martian atmosphere in the 2.3 – 4.2 µm spectral range using the Solar Occultation technique. ACS-MIR has now provided infrared observations of the Martian atmosphere over more than one and a half regular Martian Year since the end of the 2018/MY34 Global Dust Storm (GDS).

We analyzed this ACS-MIR dataset to detect the presence of water ice particles in the Martian atmosphere and retrieve their size from the 3 μm atmospheric absorption signature. Each observation results in a vertical profile of ice particle size within the cloud layer, with a vertical resolution of a few kilometers. The temporal and spatial sampling provided by the 2-hour period of TGO’s orbit allows us to observe the seasonal and latitudinal trends of the water ice clouds, with variations of about 20 to 40 km of the cloud’s altitude.

The method was first applied solely to the 2018/MY34 GDS year (Stcherbinine et al., 2020). This first study notably revealed the presence of small-grained clouds at very high altitudes (above 100 km) at the onset of the MY34 GDS, along with the presence of large water ice particles (reff > 1.5 µm) up to 65 km during the storm.

Data acquired during MY35, where no GDS occurred, provides a reference to be compared with the observations obtained during the MY34 GDS. We observe that the maximum altitude of the water ice clouds increases by about 10 km during the GDS compared to a nominal year, which suggests that the GDS significantly impacts water ice cloud distribution.

How to cite: Stcherbinine, A., Montmessin, F., Vincendon, M., Wolff, M., Korablev, O., Fedorova, A., Trokhimovskiy, A., Lacombe, G., Baggio, L., Irbah, A., and Braude, A.: Monitoring of Martian water ice clouds over one Martian Year with TGO/ACS-MIR, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-1114, https://doi.org/10.5194/egusphere-egu22-1114, 2022.

11:07–11:12
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EGU22-10508
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Presentation form not yet defined
Interannual variations of CO2 deposit in Martian caps from the HEND/Odyssey data.
(withdrawn)
Maxim Litvak, Igor Mitrofanov, and Anton Sanin
11:12–11:17
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EGU22-13086
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ECS
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Virtual presentation
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Dmitry Shaposhnikov, Mykhaylo Grygalashvyly, Alexander S. Medvedev, Gerd Reinhold Sonnemann, and Paul Hartogh

Observations of excited hydroxyl (OH*) emissions are broadly used for inferring information about atmospheric dynamics and composition. It plays an important role in the photochemical balance and is affected by transport and mixing processes. We present several analytical approximations for characterizing the hydroxyl layer in the Martian atmosphere. They include OH* number density at the maximum and the height of the peak, along with the relations for assessing different impacts on the OH* layer at nighttime conditions. These characteristics are determined by the ambient temperature, atomic oxygen concentration and their vertical gradients. The derived relations can be used for analysis of airglow measurements and interpretation of its variations.

How to cite: Shaposhnikov, D., Grygalashvyly, M., Medvedev, A. S., Sonnemann, G. R., and Hartogh, P.: Simplified Relations for the Martian Nighttime Hydroxyl Layer Suitable for Interpretation of Observations, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-13086, https://doi.org/10.5194/egusphere-egu22-13086, 2022.

11:17–11:22
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EGU22-6027
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On-site presentation
Ricardo Hueso, Claire Newman, Asier Munguira, Agustín Sánchez-Lavega, Mark Lemmon, Teresa del Río-Gaztelurrutia, Mark Richardson, Víctor Apestigue, Daniel Toledo, Álvaro Vicente-Retortillo, Manuel de la Torre-Juarez, Jose Antonio Rodríguez-Manfredi, Leslie Tamppari, Ignacio Arruego, Naomi Murdoch, Germán Martínez, Sara Navarro, Javier Gómez-Elvira, Mariah Baker, and Ralph Lorenz and the Mars 2020 Atmosphere Team

The Mars 2020 Perseverance rover landed in Mars in February 2021 in Jezero crater at 18.4ºN. One of its instruments is MEDA, the Mars Environmental Dynamics Analyzer, which measures among other properties air pressure, air temperature at different levels, surface temperature from its infrared emission, and the presence of dust. The latter is provided by a set of photodiodes pointing in different directions that constitute the Remote Dust Sensor or RDS. MEDA data are acquired with a frequency of 1 or 2 Hz in data sessions that cover about 50% of a full sol allowing a full characterization of daily and seasonal cycles.

Predictions before landing indicated that Jezero should be a location favoring the formation of intense vortices and dust devils in Spring to Summer. These expectations were fulfilled with frequent observations of vortices and dust devils observed with MEDA and the rover cameras. A systematic analysis of MEDA’s pressure sensor shows the close passage of convective vortices. These are detected as events that range from short and sharp pressure drops to long and deep pressure drops. Wind measurements during the vortex passage, combined with their duration, give information about the size and distance of the vortex. Many of the most intense events in terms of the pressure drop and peak winds detected have simultaneous drops of light measured with the RDS and are dust devils equivalent to those observed at much higher distances with Perseverance cameras. The combination of pressure, wind and RDS measurements largely constrain the geometry effects associated to these close passing dust devils. Some of them also have additional clear counterparts in other MEDA sensors including temperatures, which allows for an in-depth investigation of the physical properties of selected dust devils. Some events might also be captured by the SuperCam microphone, that records pressure fluctuations in the audible domain. The acoustic signal can provide insights into the short term behavior of vortices, and can contribute to the determination of the vortex physical properties. Statistics of vortices allow us to determine the probability of finding these events with the SuperCam microphone.

We present results for over one Earth year (Ls=6; Feb. 2021, Northern Hemisphere Spring – Ls=180; Feb. 2022; Northern Autumn Equinox). We show the daily cycle of vortex and dust devil activity and how this has evolved from early Spring until the start of the dust storms season. We present results of the distribution of sizes of vortices and dust devils and a selection of some remarkable events. These include direct hits of dust devils passing right through Perseverance, tangential passes in which one wall of the vortex passes over Perseverance, and more distant passages of very dusty events whose diameter in some cases largely exceed 100 m. A comparison of the vortex convective activity observed at Jezero with results from a Large-Eddy-Simulations (LES) using the MarsWRF model helps us to gain insight into how the detected vortices and their properties can constrain other general properties of the atmospheric dynamics at Jezero crater.

How to cite: Hueso, R., Newman, C., Munguira, A., Sánchez-Lavega, A., Lemmon, M., del Río-Gaztelurrutia, T., Richardson, M., Apestigue, V., Toledo, D., Vicente-Retortillo, Á., de la Torre-Juarez, M., Rodríguez-Manfredi, J. A., Tamppari, L., Arruego, I., Murdoch, N., Martínez, G., Navarro, S., Gómez-Elvira, J., Baker, M., and Lorenz, R. and the Mars 2020 Atmosphere Team: Seasonal variation of vortex and dust devil activity on Jezero and physical characterization of selected events, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6027, https://doi.org/10.5194/egusphere-egu22-6027, 2022.

11:22–11:49
Lunch break
Chairpersons: Gene Schmidt, Maurizio Pajola
13:20–13:22
13:22–13:27
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EGU22-7683
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ECS
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Virtual presentation
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Evandro Balbi, Paola Cianfarra, Gabriele Ferretti, Laura Crispini, and Silvano Tosi

Unravelling the tectonic styles that affected the Martian crust is crucial to better understand the evolutionary stages that a rocky planet can experience. Here, we explore the tectonic setting of a key region of Mars, namely the Claritas Fossae (CF). The CF is located in the Highlands to the south-west of the Valles Marineris and is characterized by an elongated system of scarps and troughs, fault sets, and grabens, nearly N-S trending. These morphotectonic features strongly resemble terrestrial grabens (e.g.; Thingvellir in south Iceland) and, for this reason, the CF has been interpreted as a rift-like system (Hauber & Kronberg, 2005).

In this work we apply a kinematic numerical forward modelling (HCA method; Salvini & Storti, 2004) to reproduce the geometry of the main fault(s) that likely generated the CF in order to better understand the leading tectonic mechanisms. This method allows replicating the superficial morphologies by considering the development of one or multiple faults with given geometry, throw and displacement rate and the relative movement between hanging-wall and foot-wall crustal blocks. It has been successfully used to simulate tectonically controlled morphologies on Earth such as ice buried landscape in the interiors of Antarctica (Cianfarra & Salvini, 2016), a negligible erosional environment considered as a good Martian analogue. In our model, we reproduced the morphology of the central-northern sector of the CF, characterized by an asymmetric valley with a steeper eastern slope and a gently rounded western one, along a topographical profile perpendicular to the strike of the main structure. The eastern valley slope allows locating the upper tip of the fault for the modelling in which we set the crustal thickness (i.e., the bottom of the model) to 70 km (Watters et al., 2007), considered no significant rheological vertical variation and tried different values of initial dip in the range 50°-70° and throw in the range  1000-2000 m. The preliminary results of our modelling show that the topography, including the rounded shape of the western slope, is well replicated by a crustal (listric) normal fault characterized by an initial dip of ca. 60° that gently decrease to ca. 40° and a throw of ca. 1800 m. This allows including the development of the CF in a past extensional tectonic regime of regional relevance. Further modelling on new topographical profiles to the north and to the south respect to the already modelled one will allow better highlighting the 3D shape of the main CF fault and the presence of further secondary but not negligible faults.

Hauber, E., & Kronberg, P. (2005). The large Thaumasia graben on Mars: Is it a rift?. J. Geoph. Research: Planets

Salvini, F., & Storti, F. (2004). Active-hinge-folding-related Deformation and its Role in Hydrocarbon Exploration and DevelopmentInsights from HCA Modeling.

Cianfarra, P., & Salvini, F. (2016). Origin of the adventure subglacial trench linked to Cenozoic extension in the East Antarctic Craton. Tectonophysics

Watters, T. R., McGovern, P. J., & Irwin Iii , R. P. (2007). Hemispheres apart: The crustal dichotomy on Mars. Annu . Rev. Earth Planet. Sci.

How to cite: Balbi, E., Cianfarra, P., Ferretti, G., Crispini, L., and Tosi, S.: Modelling the extensional tectonic setting of the Claritas Fossae, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7683, https://doi.org/10.5194/egusphere-egu22-7683, 2022.

13:27–13:32
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EGU22-3118
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On-site presentation
Maurizio Pajola, Martin Mergili, Pamela Cambianica, Alice Lucchetti, Maria Teresa Brunetti, Anthony Guimpier, Maria Mastropietro, Giovanni Munaretto, Susan Conway, Joel Beccarelli, and Gabriele Cremonese

We study a young (~ 4.5 Ma), 3.4 km long landslide located in the floor of Simud Vallis, a large outflow channel that together with Tiu Vallis once connected the Valles Marineris with the Chryse Planitia on Mars (1). Multiple teardrop-shaped islands are present on Simud Vallis’ floor, all elongated in the S–N direction of the flow (2) that incised the Mid-Noachian plateau (3). The Simud Vallis (SV) landslide is located on the western side of one of such landforms. It is characterized by numerous boulders on its deposits (4). By making use of the 2 m-scale HiRISE DEM of (4) we reconstruct the terrain surface before the SV landslide. We thereby estimate the release and deposition heights and volumes related to the rotational slide of the landslide, called stage 1, and of the subsequent flow, called stage 2. Using the r.avaflow software (5) we simulate the mass movement of stage 2 and obtain simulated deposits that are comparable to the current landslide deposit in terms of both horizontal extent and thickness (6). Through two 0.25 m-scale HiRISE images we identify and manually count >130,000 boulders that are located along the landslide, deriving their size-frequency distribution and spatial density per unit area for boulders with an equivalent diameter ≥1.75 m. Our analyses (6) shows that the distribution is of a Weibull-type (7), which commonly results from sequential fragmentation and it is often used to describe the particle distribution derived from grinding experiments (8,9). This suggests that the rocky constituents of the SV landslide fractured and fragmented progressively during the course of the mass movement, consistent with our proposed two-stage model of landslide motion.

References:

 (1) Pajola, M. et al., 2016. Icarus, 268, 355. (2) Carr, M.H. & Clow, G.D., 1981. Icarus, 48 (1), 91. (3) Tanaka, K.L. et al., 2014. US Geological Survey. (4) Guimpier, A., et al., 2021. PSS, 206, 105303. (5) Mergili, M., et al., 2017. Geosci. Model Dev. 10, 553. (6) Pajola, M. et al., 2022. Icarus, 375, 114850. (7) Weibull, W., 1951. J. Appl. Mech., 18, 837. (8) Brown, W.K. & Wohletz, K.H., 1995. J. Appl. Phys. 78, 2758. (9) Turcotte, D.L., 1997. Cambridge University Press, Cambridge.

How to cite: Pajola, M., Mergili, M., Cambianica, P., Lucchetti, A., Brunetti, M. T., Guimpier, A., Mastropietro, M., Munaretto, G., Conway, S., Beccarelli, J., and Cremonese, G.: Mass movement reconstruction and boulder size-frequency distribution of the Simud Vallis landslide, Mars, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3118, https://doi.org/10.5194/egusphere-egu22-3118, 2022.

13:32–13:37
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EGU22-10765
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On-site presentation
Natalia Zalewska, Leszek Czechowski, and Jakub Ciążela

Many cones on Isidis Planitia form subparallel chains several kilometers in length. This region have characteristic pattern of cones or cone chains- called a “fingerprint” [1]. Our analysis of chains of cones indicates that they can be grouped in larger systems. We considered one of these systems in the northwestern part of Isidis (central location: 14.235°N; 83.096°E).

We selected one standout spectrum that comes from the CRISM FRT00009260 scene but is typical for the entire image area. The scene just comes from the northwestern part of Isidis, where the characteristic chains of cones are visible. The types of cones from our division [2], belong to the group of chains of separate cones and without a furrow. The spectrum shows the minima 1.49; 1.98; 2.04 µm which we assigned to individual minerals. Additionally, the ~ 2 µm range is disturbed by Martian CO2 influences, which is caused by the imperfect separation of the atmosphere by the “volcano - scan algorithm” (by the atmosphere above Olympus Mons). Gypsum appears to be the most suitable mineral for these minima, although alunites can also be considered. The clay minerals widespread on Mars do not resemble in the observed minima. From the generated endmembers, it can be seen that minerals are accumulated around the cones.

Gypsum is a mineral formed in the process of evaporation and crystallizes from salty, drying water reservoirs. Because Isidis might once have been a highly saline reservoir, gypsum crystallization could occur under such conditions, especially in depressions. Alunites, on the other hand, are products of volcanic exhalation, which would explain the origin of the cones. Common alunites have been found on the La Fossa Crater Volcano, Aeolian Islands [3] as volcanic exhalations and in the vicinity of Las Vegas, Nevada, where alunites with gypsum were mapped based on aerial photos [4]. On Mars in the northeast of Hellas Basin, gypsum and ammonioalunites were interpreted on the basis of the PFS and OMEGA (MEX) spectra [5], [6]

These are our preliminary comparisons that still require further evaluation. The next stage of the work will be to explain the mechanism of the formation of these forms, based on known geological phenomena but in relation to Mars. We want to clarify whether the designated areas were created in the same geological processes, or whether a different mechanism is responsible for the differences in these forms. We take the phenomenon into account that instability of water in the upper layers of the regolith could cause rapid degassing of the regolith [7].

References: [1] Guidat, T. et al. (2015) Earth and Planet. Sci. Let . 411, 253-267. [2] Zalewska N. et al. (2021) LPS 52nd, Abstract # 2710. [3] Parafiniuk J. (2012) Bulletin of the Polish Geolog. Instit. 452, 225-236. [4] Kirkland E. et al. (2007) LPS XXXVIII, Abstract # 2232. [5] Zalewska N. (2013) Planet. Space Sci. 78, 25-32. [6] Zalewska N. (2014) GeoPl. Earth and Planet. Sci. 65-76. [7] Czechowski L. et al. (2021) LPS 52nd, Abstract # 2740.

How to cite: Zalewska, N., Czechowski, L., and Ciążela, J.: Mineralogy of cones in the western part of Isidis Planitia, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-10765, https://doi.org/10.5194/egusphere-egu22-10765, 2022.

13:37–13:42
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EGU22-9874
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ECS
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On-site presentation
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Lucie Riu, John Carter, and François Poulet

In the past decades, numerous hydrated silicates have been detected at the surface of Mars from orbital and in situ characterization. The study of their distribution and their quantification can enable to trace the history of water at the surface of the red planet. By quantifying the content of each minerals at the hydrated sites, we can have an estimation of the water content stored at the surface within these minerals. Our study is based on the modal compositional maps of 11 hydrated silicates that were detected with the OMEGA/MEx instrument (Observatoire pour la Minéralogie, l’Eau, les Glaces et l’Activité). The maps were computed using a radiative transfer model applied to the hyperspectral images of OMEGA, where hydrated minerals features were previously detected. They results in global maps of modal composition at a resolution sub-kilometric of: Fe,Mg,Al-phyllosilicates, Al-smectite, AlSiOH, Opal, Mg-carbonates, Chlorite, Fe/Mg-Micas, Serpentine and Fe-hydroxide and were recently published in Riu et al., 2022. By estimating the water content of each individual end-members we were able to convert the 11 mineralogical maps into one final map of H2O content (in wt%). The average content of water, based on the content stored in hydrated silicates, is estimated to be slightly above 5 wt%, with some rare occurrences > 20 wt%. The ongoing studies now aim at a detailed analysis of the water distribution in order to look for new regions with high past aquability (stable liquid water) potential and/or exobiological potential, if such locations exist. The map will be studied locally in combination with high resolution images in order to correlate the high-water content with their context and highlight new regions of interest. A detailed analysis of the ExoMars22 Rosalind Franklin Rover is also foreseen in order to help the future in situ analysis of the ExoMars mission and contribute to ISRU (in situ ressource utilization).

How to cite: Riu, L., Carter, J., and Poulet, F.: Estimation of H2O content (in wt%) stored in hydrated silicates at Mars, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9874, https://doi.org/10.5194/egusphere-egu22-9874, 2022.

13:42–13:47
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EGU22-10258
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Virtual presentation
Global Distribution of Hydrogen Content in the Martian Subsurface as Seen by the FREND Neutron Telescope Onboard ExoMars TGO
(withdrawn)
Alexey Malakhov, Igor Mitrofanov, Anton Sanin, Maxim Litvak, Dmitry Golovin, Maya Djachkova, Nikita Lukyanov, Sergey Nikiforov, Artem Anikin, and Denis Lisov
13:47–13:52
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EGU22-3191
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ECS
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On-site presentation
Christopher Gerekos, Gregor Steinbrügge, Elena Donini, and Andrew Romero-Wolf

Passive radar sounding has been proposed as a low-cost, low-risk way to enrich the scientific return of planetary radar sounders, especially in the vicinity of bright radio sources such as Jupiter [Romero-Wolf et al. (2015), Icarus, 248:463-477], whose moons will be studied by radar sounders in the late 2020's and 2030's. To predict what passive radargrams may look like as a function of parameters such as the noise source spectrum and the surface/subsurface roughness, analytical and empirical models have been proposed in the literature [Schroeder et al. (2016), PSS, 134:52-60], and proof-of-concept hardware has been tested on Earth [Peters et al. (2018), TGRS, 56(12) 7338-7349]. To cement our understanding of passive sounding, we searched for traces of passively-acquired radar echoes in existing SHARAD radargrams. Such signals can be uncovered if the incoming noise was captured in one acquisition and its reflection by surface or subsurface features in the next one. Cross-correlating the two uncompressed rangelines could then reveal possible present Martian features using only the signals of opportunity. We started from the engineering parameters of SHARAD, such as its orbit, Rx window length, and PRF, to work out all the geometric configurations where Jovian emissions and their reflection from the surface could have been intercepted if such emissions were present. We made the assumption that waves must be specularly-reflected off the surface of Mars at a given angle, and looked for the angles at which the delay of the reflected noise matches the PRI of SHARAD. We have determined that, for the range of altitudes SHARAD operates at, the (Jupiter-Mars, Mars-SHARAD) angle must lie between 35° and 52°. Based on Friis-like arguments, we believe the SNR of such signals could reach 10 dB in the case of a smooth surface such as Elysium Planitia. We then cross-correlated this database of SHARAD radargrams with that of a model of Jovian noise occurrence at Mars using ExPRES [Hess et al. (2008), GRL, 35.13], and extracted a list of potential candidates. Preliminary analysis of these candidates shows that some of them may indeed contain passively-acquired signals that may be exploited scientifically. We have additionally conducted passive Stratton-Chu simulations [Gerekos et al. (2019), TGRS, 58(4) 2250-2265] of these cases to support interpretation.

How to cite: Gerekos, C., Steinbrügge, G., Donini, E., and Romero-Wolf, A.: Exploitation of SHARAD data from a passive sounding perspective: a preliminary analysis, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3191, https://doi.org/10.5194/egusphere-egu22-3191, 2022.

13:52–13:57
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EGU22-13476
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ECS
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On-site presentation
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Aleksandra Sokolowska, Nicolas Thomas, and Kai Wünnemann
Mars is a cold dry planet, yet there is ample evidence for fluvial activity on its past surface, including sediments suggestive of shallow lakes, which paints a different picture for the Martian past climate. Mars is also heavily cratered, and some of those craters may have resulted from impact cratering into water-covered targets. Distinguishing between water-overed and dry surface at the time of the impact is the topic of this project. We approach this problem from the theoretical point of view and use a shock physics code iSALE capable of simulating different materials with various strength and damage models. This hydrocode is widely used in impact physics and has been extensively tested against laboratory experiments. We realise several impact scenarios with varied rheology, as well as sizes of projectiles and impact angles, in particular water-covered (simulated paleolake), water ice-rich and dry targets. We discuss the theoretical effects of the presence of surface water on the morphology and dynamics of impact sites (both craters and ejecta). Distinguishing between these scenarios can aid the interpretation of remote sensing observations, and open a possibility of using a new independent observable to study the past climate of Mars.

How to cite: Sokolowska, A., Thomas, N., and Wünnemann, K.: Impact cratering into water-covered targets on Mars, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-13476, https://doi.org/10.5194/egusphere-egu22-13476, 2022.

13:57–14:02
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EGU22-12988
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ECS
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On-site presentation
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Hector-Andreas Stavrakakis, Dimitra Argyrou, and Elias Chatzitheodoridis

Since the 90s, an ever-increasing number of missions to Mars have been conducted which offer a plethora of information about the red planet. This information also led to the rapid development and advancement of prominent scientific fields in space and planetary exploration, such as astrobiology and ISRU technologies. The experimentation and research requirements of those fields, as well as, the need for better vehicle and instrument testing for further development, so that they will better operate on Martian conditions and its surface, increase in significance. Currently, this is performed with the use of natural (Analogue) and synthetic (Simulant) Geomaterials. 

However, the accessibility and the analysis of analogue and simulant data requires a thorough literature review in order to  identify implications for future research. In our latest research work, we conducted this detailed review and we identified, grouped, and analysed a number of implications that pertain mostly to the synthesis procedures of simulants, but also extend to the in situ analytical data from Mars that are used as a reference. Furthermore, we identified an urgent need for improving the current state of simulant research, as it is currently very time consuming and has implications, in hope that systematic work on the topic will culminate in a general standardisation effort.

The current work was done by analysing data on all available simulant geomaterials in order to provide recommendations and suggestions for mitigation actions for their development and their use during research, as well as to advocate the needs for a unified standardisation system. These actions include: (a) the consolidation of existing literature into database formats with easy access, based on (b) the development of a new informational construct based on ontologies and semantics, (c) to propose a classification system for simulants that is missing from the literature, and (d) assist the simulant geomaterial selection process through a proposed step algorithm. The ontological and semantic mindset should be followed at every step, and it is incorporated into the classification system, thus enabling easy access and interpretation by both humans and machines. This set of tools and recommendations should be applicable on all simulant related facets of space exploration.

 

How to cite: Stavrakakis, H.-A., Argyrou, D., and Chatzitheodoridis, E.: A new classification and terminology system towards the development and utilisation of Martian simulants, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12988, https://doi.org/10.5194/egusphere-egu22-12988, 2022.

14:02–14:07
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EGU22-12535
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ECS
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On-site presentation
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Gene Schmidt, Erica Luzzi, Fulvio Franchi, Ame Thato Selepang, Kabelo Hlabano, and Francesco Salvini

Across the surface of Mars there is evidence of past lacustrine and evaporitic environments found within basins and craters, where often layered sedimentary deposits and hydrated minerals are observed. However, the intensity, duration and precise phases of water cycle activity during their deposition remain unresolved. Although several geological processes and locations on Earth have been previously proposed as examples to describe these deposits on Mars, we lack a strong visualization of what water activity might have looked like during evaporitic stages within basins and craters. The Makgadikgadi Salt Pans of Botswana, where once the Makgadikgadi Lake existed, is a present evaporitic environment rich in hydrated minerals and water activity. It is a depression located at the southwestern end of a northeast-southwest set of graben. Faults have been previously proposed to have been pathways for groundwater to enter basins and craters on Mars, which then contributed to both the deposition and alteration of the sedimentary deposits. Thus, imaging the subsurface of a similar environment on Earth can help us to better understand how water processes on Mars might have continued as the Martian global climate became drier.

Through remote sensing techniques, we located areas within the pans where several regional faults occurred then conducted four electrical resistivity surveys perpendicular to the faults using an IRIS Syscal Pro imaging resistivity meter. Fault locations were determined by using a combination of topographic and aeromagnetic data. Fault scarps were observed terminating at the shorelines of the pans and their azimuths were used to trace the best locations of the faults underneath the sediment within the pans. These locations were then constrained further by using the aeromagnetic data which showed regional dikes that had been laterally offset in areas associated with the fault scarps, as well as anomalies that ran parallel and adjacent to the fault scarps. We successfully laid one 840 m and three 1,200 m long survey lines. The four survey lines intersected where these faults were determined to occur and were able to image the subsurface up to a depth of approx. 92 m.

In this way, we can detect low electrical resistance in void space produced by any faults and associated fractures in the overlaying water saturated sediment. Specific craters noted for their similarity to the study area include several in Arabia Terra (e.g. Oyama, Kotido, Firsoff and Jiji), and also Gale crater. The analog concept could also potentially be connected to layered deposits in Meridiani Planum and Valles Marineris. This work has wide implications for determining how putative water table elevations could have interacted within sediment filled craters on Mars by resolving areas of low resistivity and identifying faults that water could have used as pathways, which is not possible with the current instrumentation present on Mars. Results can also allow us to better infer what the underlying lithology of layered deposits within craters might look like. Furthermore, it demonstrates the scientific importance of future missions to employ subsurface imaging techniques on Mars.

How to cite: Schmidt, G., Luzzi, E., Franchi, F., Selepang, A. T., Hlabano, K., and Salvini, F.: Constraining the Movement of Groundwater Within Playa Environments on Mars Through Subsurface Imaging of the Makgadikgadi Salt Pans of Botswana, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12535, https://doi.org/10.5194/egusphere-egu22-12535, 2022.

14:07–14:12
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EGU22-3094
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ECS
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Virtual presentation
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Andebo A. Waza, Jonathan P. Merrison, Jens J. Iversen, and Keld R. Rasmussen

Wind driven dust resuspension is actively and ubiquitously observed at the surface of Mars, however the mechanisms involved, and conditions required are poorly understood (Neakrase et al., 2016). The objective of this laboratory study is to investigate various dust resuspension mechanisms using a unique set of recirculating environmental wind tunnel facilities at Aarhus University (Holstein-Rathlou et al., 2014). This study employs various sensor techniques including digital microscopy and optical reflectance to quantify dust removal as well as Laser Doppler Velocimetry and optical opacity measurement for determining dust concentration (Jakobsen et al., 2019). Importantly in these studies the dust was deposited from suspension within an environmental wind tunnel (Merrison et al., 2008).

Already from preliminary experiments significant advancements in our knowledge of dust resuspension have been made. Specifically, for the first time under Martian conditions direct wind driven dust remobilization has been observed (Rondeau et al., 2015). As expected, the process involved dust aggregate detachment and transport. Also for the first time saltation induced dust resuspension has been recreated (i.e. impact induced dust resuspension) from a loose sand bed coated with dust. Interestingly preliminary estimates have shown that both of these mechanisms appear to have similar values of threshold shear stress of around 0.07Pa, this is close to the expected threshold for saltation (Andreotti et al., 2021). It is hoped that both the resuspension flux and threshold can be quantified.

These studies are part of an international EU supported research project called ROADMAP (https://roadmap.aeronomie.be/). Three Mars analogue dust prototypes ‘are being used in these experiments. These have been developed and characterized by the ROADMAP team.

Acknowledgments

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 101004052.

References

Andreotti, B., Claudin, P., Iversen, J. J., Merrison, J. P., and Rasmussen, K. R.: A lower-than-expected saltation threshold at Martian pressure and below, Proceedings of the National Academy of Sciences, 118, 2021.

Holstein-Rathlou, C., Merrison, J., Iversen, J., Jakobsen, A., Nicolajsen, R., Nørnberg, P., Rasmussen, K., Merlone, A., Lopardo, G., and Hudson, T.: An environmental wind tunnel facility for testing meteorological sensor systems, Journal of atmospheric and oceanic technology, 31, 447-457, 2014.

Jakobsen, A. B., Merrison, J., and Iversen, J. J.: Laboratory study of aerosol settling velocities using laser Doppler velocimetry, Journal of Aerosol Science, 135, 58-71, 2019.

Merrison, J. P., Bechtold, H., Gunnlaugsson, H., Jensen, A., Kinch, K., Nornberg, P., and Rasmussen, K.: An environmental simulation wind tunnel for studying Aeolian transport on mars, Planetary and Space Science, 56, 426-437, 2008.

Neakrase, L., Balme, M., Esposito, F., Kelling, T., Klose, M., Kok, J., Marticorena, B., Merrison, J., Patel, M., and Wurm, G.: Particle lifting processes in dust devils, Space Science Reviews, 203, 347-376, 2016.

Rondeau, A., Merrison, J., Iversen, J. J., Peillon, S., Sabroux, J.-C., Lemaitre, P., Gensdarmes, F., and Chassefière, E.: First experimental results of particle re-suspension in a low pressure wind tunnel applied to the issue of dust in fusion reactors, Fusion Engineering and Design, 98, 2210-2213, 2015.

How to cite: Waza, A. A., Merrison, J. P., Iversen, J. J., and Rasmussen, K. R.: Laboratory study of dust resuspension mechanisms in the Martian Environment, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3094, https://doi.org/10.5194/egusphere-egu22-3094, 2022.

14:12–14:17
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EGU22-12286
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Presentation form not yet defined
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Agata M Krzesinska, Benjamin Bultel, and Stephanie C Werner

Planetary Terrestrial Analogue Library (PTAL) is a newly built collection of rocks and spectral data aiming to support interpretation of data from Mars and small bodies of the Solar System [1]. It contains spectral data by NIR, Raman and LIBS, validated by XRD and microscopic characterization [2,3,4]. Since September 2021, the PTAL library is public and freely accessible (www.ptal.eu), and the physical collection of witness rocks is available for further studies. PTAL is collection of natural rocks and not individual minerals what gives better insight into mineralogy and geochemistry as e.g. overlapping vibrational absorption features of minerals are included. Although the spectral analogy never implies exact parallelism in processes of deposit formation, reliable identification of specific minerals can shed light on recorded evolution and alterations. Here we present the overview of analogues and assess their fidelity in terms of information about composition (mineralogy and geochemistry) of Martian crust and alteration environments.

PTAL consists of 106 rock samples from 19 diverse localities on Earth [1]. The collection contains a variety of volcanic rocks, from picrobasalts to phonolites. Sampling sites include tholeiitic basalts from Iceland, ferropicrites from Rum (Scotland), alkali-rich rocks of metasomatized origin from Canary Islands and Tenerife, basaltic tuffs and ash-fall deposits from the Granby formation (USA) with clay-infilled amygdales, as well as serpentinised peridotites from the Leka ophiolite complex (Norway). Collected rocks are good analogues for processes of martian mantle-plume fed volcanism as well as for evolution of alkali-rich crustal units on Noachian Mars. Additionally they record processes of metasomatism, deuteric and hydrothermal alteration. They are never perfect geochemical analogues to Martian crust, which is a consequence of inherited differences between the two planets, e.g. Fe and Mn content or volatile abundances. PTAL initial studies show, however, that studies of alteration pathways as a function of protolith composition are possible with these rocks, despite geochemistry mismatches [5].

PTAL contains also samples from diverse surface alteration environments and from range of climatic environments, including hot and cold deserts: John Day Formation in Oregon (USA), Dry Valleys in Antarctica, Otago Formation (New Zealand), Jaroso Ravine and Rio Tinto (Spain). These analogues contain minerals such as jarosite, hematite, or Fe-rich vermiculite and therefore good geochemical and mineralogical analogies to Mars targeted sites can be obtained. However, care is needed when processes of formation inferred [e.g. 5], as peculiar conditions leading to formation of minerals can be obtained in a spectrum of environments. PTAL strength is that it samples a sequence of alteration products, allowing detailed mineralogical and geochemical comparative analyses within alteration environment to shed light on the potential parallelism of formation process [5].

Acknowledgement: PTAL was funded by the EU Horizon 2020 Research and Innovation Programme (Grant Agreement 687302).

[1] Dypvik et al., 2021. Planetary and Space Science 208, 105339

[2] Lantz et al., 2020. Planetary and Space Science 189: 104989

[3] Loizeau et al., 2022. Astrobiology, accepted.

[4] Veneranda et al., 2020. Journal of Raman Spectroscopy 51: 1731-1749

[5] Krzesinska et al. 2021. Astrobiology 21: 997-1016

How to cite: Krzesinska, A. M., Bultel, B., and Werner, S. C.: Analogues for Martian crustal and aqueous processes: Lessons learnt from mineralogy and geochemistry of rocks in the PTAL collection., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12286, https://doi.org/10.5194/egusphere-egu22-12286, 2022.

14:17–14:22
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EGU22-11272
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ECS
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Virtual presentation
Benjamin Bultel, Agata Krzesinska, Marco Veneranda, Damien Loizeau, Cédric Pilorget, Vincent Hamm, Lionel Lourit, Guillaume Lequertier, Jean-Pierre Bibring, and Stephanie C. Werner

In 2022, ESA/ROSCOSMOS will launch ExoMars2022 rover mission to Mars. The selected landing site for the mission is Oxia Planum, a Noachian, phyllosilicate-bearing plain located between Mawrth Vallis and Ares Vallis. The Fe,Mg-rich clay mineral detected at Oxia Planum are one of the largest exposures of this type on Mars. They clearly record past water-rock interactions and as such are promising target to answer scientific questions that are the objectives of the ExoMars 2022 mission in terms of past water-rich environment and both ancient and present habitability of the planet.

NIR spectral features of the phyllosilicates at Oxia suggest some kind of Fe-rich vermiculite and/or saponite. Survey of Fe-rich terrestrial vermiculite-bearing rocks and characterization by powder near-infrared and X ray diffraction analyses (Krzesinska et al, 2021) showed that the best spectral analogy is shown by the basaltic tuffs from Granby, Massachusetts, USA. The tuffs have been altered and Fe-rich clays resides in amygdales of supposedly hydrothermal origin (April and Keller, 1991).

The analogue was incorporated to the Planetary Terrestrial Analogue Library (PTAL) collection (Dypvik et al., 2021, www.ptal.eu). As a part of collection, it is further characterized for purposes of supporting the ExoMars mission science.

As shown by bulk analysis of powdered samples, Granby tuffs represent fine-scale mixture of phyllosilicates (Krzesinska et al., 2021). Based on bands between 2.3 and 2.5µm in NIR, vermiculite and saponite are intergrowing with various proportions. For Oxia Planum, better spectral match is shown by samples dominated by vermiculite rather than mixed with saponite.

Here we report an in-situ, micron-scale combined analysis on the same sample by the instrument of MicrOmega (NIR), RLS (RAMAN) completed by sub-micron EDX analysis. Such analysis allows a more detailed characterization of phyllosilicate constituents and understanding their spectral manifestation. This is important to prepare the future in situ scientific investigations on Mars and will also bring a better understanding of the Granby clays that could represent a unique bridge of solid solution between chlorite and saponite (April and Keller, 1991).

How to cite: Bultel, B., Krzesinska, A., Veneranda, M., Loizeau, D., Pilorget, C., Hamm, V., Lourit, L., Lequertier, G., Bibring, J.-P., and Werner, S. C.: Micro-scale characterization of vermiculite-rich sample from Granby Tuff, an analogue to Oxia Planum clays, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-11272, https://doi.org/10.5194/egusphere-egu22-11272, 2022.

14:22–14:49
Coffee break
Chairperson: Stephan Ulamec
15:10–15:12
15:12–15:17
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EGU22-10731
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ECS
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Highlight
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Presentation form not yet defined
Michael Chaffin, Hoor Almazmi, Krishnaprasad Chirakkil, John Correira, Justin Deighan, Scott England, J. Scott Evans, Matthew Fillingim, Greg Holsclaw, Sonal Jain, Rob Lillis, Fatma Lootah, Susarla Raghuram, and Hessa Al Matroushi

The Emirates Mars Ultraviolet Spectrometer (EMUS) instrument is one of three science instruments on board the “Hope Probe” of the Emirates Mars Mission (EMM). EMM arrived at Mars on February 9 2021, in order to explore the global dynamics of the Martian atmosphere, while sampling on both diurnal and seasonal timescales. The EMUS instrument is a far-ultraviolet imaging spectrograph, jointly developed by the Mohammed Bin Rashid Space Centre (MBRSC) in Dubai, UAE and the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder, which measures emissions in the spectral range 100-170 nm. Using a combination of its one-dimensional imaging and spacecraft motion, it makes two-dimensional far-ultraviolet images of the Martian disk and near-space environment including the Lyman beta and alpha atomic hydrogen emissions (102.6 nm and 121.6 nm), two atomic oxygen emissions (130.4 nm and 135.6 nm), and the carbon monoxide fourth positive group band emission (140-170 nm). Measurements of radiance at these wavelengths are used to derive the column abundance of atomic oxygen and carbon monoxide in the Martian thermosphere, and the density of atomic oxygen and atomic hydrogen in the Martian exosphere both with spatial and sub-seasonal variability. We will present a survey of results from EMM/EMUS including observed variability in atomic oxygen and carbon monoxide emission, two kinds of aurora, and the status of atmospheric retrievals.

How to cite: Chaffin, M., Almazmi, H., Chirakkil, K., Correira, J., Deighan, J., England, S., Evans, J. S., Fillingim, M., Holsclaw, G., Jain, S., Lillis, R., Lootah, F., Raghuram, S., and Al Matroushi, H.: Key Results from the Emirates Ultraviolet Spectrometer on the Emirates Mars Mission, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-10731, https://doi.org/10.5194/egusphere-egu22-10731, 2022.

15:17–15:22
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EGU22-3727
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Highlight
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Virtual presentation
Hessa Almatroushi, Justin Deighan, Christopher Edwards, Gregory Holsclaw, and Michael Wolff and the EMM Science Team

The Emirates Mars Mission (EMM) – Hope Probe – has commenced its one-Martian-year science phase on May 23rd 2021. The goals of the mission aim to understand the Martian atmosphere, its processes, dynamics, and circulation using three scientific instruments observing Mars' different atmospheric layers simultaneously. 

Hope Probe is studying the lower atmosphere of Mars using the Emirates eXploration Imager (EXI) and the Emirates Mars Infrared Spectrometer (EMIRS). While EXI measures the distribution of water ice and ozone using ultraviolet bands, EMIRS measures the optical depth of dust, ice clouds and water vapor in the atmosphere, in addition to the temperature of the surface and the atmosphere using infrared bands. On the other hand, the Emirates Mars Ultraviolet Spectrometer (EMUS) is studying the upper atmosphere of Mars through extreme and far ultraviolet bands to measure the distribution of carbon monoxide and oxygen in the thermosphere, and oxygen and hydrogen in the exosphere of Mars.

The scientific observations are taken from a unique high-altitude orbit with dimension 20,000 x 43,000 km that offers unprecedented local and seasonal time coverage over most of the planet. This presentation will highlight key atmospheric and surface results from the Hope Probe since it started collecting scientific data on the Martian atmosphere upon arrival to Mars on February 9th 2021. The data returned from the mission is enabling us to improve our understanding of the weather circulation in the lower atmosphere, the mechanisms behind the upward transport of energy and particles, and the subsequent escape of atmospheric particles from the gravity of Mars.

How to cite: Almatroushi, H., Deighan, J., Edwards, C., Holsclaw, G., and Wolff, M. and the EMM Science Team: Results from the Emirates Mars Mission (EMM) - Hope Probe, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3727, https://doi.org/10.5194/egusphere-egu22-3727, 2022.

15:22–15:27
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EGU22-4208
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ECS
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On-site presentation
Siteng Fan, Francois Forget, Michael Smith, Sandrine Guerlet, Khalid Badri, Samuel Atwood, Christopher Edwards, Philip Christensen, Justin Deighan, Hessa Al Matroushi, Antoine Bierjon, Jiandong Liu, and Ehouarn Millour

Thermal tides are planetary-scale harmonic responses driven by diurnal solar forcing and influenced by planetary topography. Excited by solar heating absorbed by the atmosphere and energy exchange with surface, thermal tides grow in Martian atmosphere. These tides usually have large amplitudes due to the low heat capacity of Martian atmosphere, and dominate its diurnal variations. In this talk, we present results of the analysis of thermal tides in Martian atmosphere using temperature profiles retrieved using infrared spectra obtained by the Emirates Mars InfraRed Spectrometer (EMIRS) instrument onboard the Emirates Mars Mission (EMM) Hope spacecraft. The first set of data obtained during the mission science phase is selected, covering a solar longitude (LS) range 60° - 80° of Martian Year (MY) 36, which is a clear season without large dust storms. The novel orbit design of the spacecraft allows a full local time coverage to be reached within 10 Martian days, approximately ~5° of LS. It enables the analysis of diurnal temperature variations without the interference of seasonal changes, which was shown to be significant in previous studies. Wave mode decomposition is also applied to these diurnal variations, and amplitudes of other tide modes are derived. The results show good agreements with predictions derived using the Laboratoire de Météorologie Dynamique (LMD) Mars Global Circulation Model (GCM), except for a noticeable phase difference of the dominant diurnal thermal tide. This work provides valuable information on understanding diurnal variations in Martian atmosphere and inspires future advances of Mars GCMs.

How to cite: Fan, S., Forget, F., Smith, M., Guerlet, S., Badri, K., Atwood, S., Edwards, C., Christensen, P., Deighan, J., Al Matroushi, H., Bierjon, A., Liu, J., and Millour, E.: Thermal tides in Martian atmosphere observed by EMIRS onboard the Hope spacecraft, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-4208, https://doi.org/10.5194/egusphere-egu22-4208, 2022.

15:27–15:32
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EGU22-6039
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Virtual presentation
Christopher Edwards, Michael Smith, Sam Atwood, Khalid Badri, Philip Christensen, Michael Wolff, Mikki Osterloo, Eman Al Tunaiji, Noora Al Mheiri, Maryam Yousuf, Chris Wolfe, Nathan Smith, and Saadat Anwar

The Emirates Mars Mission (EMM) Emirates Mars Infrared Spectrometer (EMIRS) currently around Mars is acquiring remote measurements of the martian surface (temperature and composition) and lower atmosphere. EMIRS is a FTIR spectrometer covering the range from 6.0-100 µm (1666-100 cm‑1) with a spectral sampling as high as 5 cm-1 with a 5.4-mrad IFOV. The EMIRS optical path includes a flat 45˚ pointing mirror to enable one degree of freedom while the spacecraft provides the other to build up a 2-dimensional array of observations. The primary goals of EMIRS are to characterize the geographic and diurnal variability of key atmospheric constituents (water ice, water vapor, and dust) along with temperature profiles and surface temperature on sub-seasonal timescales

EMIRS acquires data of the full martian disk and thus provides an integrated view of the martian surface and atmosphere in every spectrum. These observations include complete diurnal, seasonal, and geographic coverage of atmospheric properties, surface temperature, and also surface composition/mineralogy at wavelengths not regularly acquired of the martian surface. Due to the unique nature of the EMM orbit, EMIRS also collects data that spans the full local solar time range (all solar incidence angles), at multiple emission angles. These unique observations permit the interrogation of diurnal surface ices/frost, thermophysics (including sub-surface layering from both a seasonal and diurnal skin depth), surface roughness, and rock abundance in addition to the primary science goals.

In this presentation, we provide an overview of the first surface observations, atmospheric retrieval algorithm, and first atmospheric science results from the aphelion-season observations taken by EMIRS over the first several months of EMM Science Phase operations.

How to cite: Edwards, C., Smith, M., Atwood, S., Badri, K., Christensen, P., Wolff, M., Osterloo, M., Al Tunaiji, E., Al Mheiri, N., Yousuf, M., Wolfe, C., Smith, N., and Anwar, S.: The Atmosphere and Surface of Mars as Revealed by the Emirates Mars Infrared Spectrometer (EMIRS), EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6039, https://doi.org/10.5194/egusphere-egu22-6039, 2022.

15:32–15:37
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EGU22-4991
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Presentation form not yet defined
Michael Wolff, Andrew R. Jones, Mikki Osterloo, Ralph Shuping, Christopher Edwards, Mariam Al Shamsi, Joey Espejo, Charles Fisher, Chris Jeppesen, and Justin Knavel

The EXI instrument is a camera onboard the EMM spacecraft, with a field a view capable capturing the full disk of Mars throughout its nominal science orbit.   Though the use of its multiple band passes (220, 260, 320, 437, 546, 635 nm) and the effective spatial resolution (2–4 km per native pixel), EXI’s primary goal is to provide both regional and global imaging of the Martian atmosphere with diurnal sampling over much of the planet on a time scale of approximately 10 days.  This presentation will provide an overview of EXI’s on-orbit instrument performance, a brief description of the observation strategy employed with the start of Science Operations (23-May-2021, Ls=49°), and the retrieval results of the ice optical depth and their diurnal behavior for the period of mid-spring through late-summer in the northern hemisphere.  More specifically, the presentation will cover:

 

  • Status of the instrument calibration and plans for on-going on-orbit monitoring of instrument performance, including radiometric errors. Plus, some guidance on interpreting the metadata of the EXI publicly released raw and calibrated images;

 

  • Illustration of the various disk geometries sampled during an EMM orbit of Mars, and how such observations are combined to provide diurnal coverage of the illuminated portion of the disk/atmosphere;

 

  • Overview of the ice optical depth retrieval algorithm, and its application to the data obtained since the start Science Operations with an emphasis on the behavior of the aphelion cloud belt; including the formation and decay phases.

How to cite: Wolff, M., Jones, A. R., Osterloo, M., Shuping, R., Edwards, C., Al Shamsi, M., Espejo, J., Fisher, C., Jeppesen, C., and Knavel, J.: The Emirates eXploration Imager (EXI) onboard the Emirates Mars Mission (EMM): Overview of In-flight Performance, and Water Ice Cloud Retrievals, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-4991, https://doi.org/10.5194/egusphere-egu22-4991, 2022.

15:37–15:42
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EGU22-982
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ECS
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Virtual presentation
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Changcheng Li and Xiaofei Chen

    Since entering the 21st century, with the progress and development of science and technology. Human exploration of the world is not limited to the earth. Remarkable achievements have also been made in the exploration and understanding of the planet. In the last century, the US completed the exploration of the internal structure of the moon by using seismological methods through the Apollo program. The successful launch of insight in 2018 marked the birth of Marsquake, and realized the preliminary exploration of the internal structure of Mars. Due to the limitation of aerospace capability, the scientific research equipment we can carry is limited. The NASA spent hundreds of millions of dollars to deploy a seismograph on Mars. However, the deployment of a single seismograph is usually difficult to accurately measure the internal structure of Mars. Because the imaging method based on the internal vibration signal of Mars requires the use of a single seismograph constraining the source information and the internal structure of Mars at the same time, Which will increase the risk of inversion multiplicity.

    The main function of placing seismometers on the planet is to monitor the internal activity law of the planet. However, if we can obtain more reliable planetary exploration data without increasing the detection cost by designing a reasonable observation system, it will play an important role in the future exploration of the internal structure of the planet.

    Thus, a single station observation system is designed, which lays a foundation for seismic imaging to obtain more controllable and reliable data through the combination of single station and moving source(Rover). In this way, we can obtain two-dimensional and three-dimensional planetary seismic profiles in the future.

 

How to cite: Li, C. and Chen, X.: One station observation system for Mars exploration, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-982, https://doi.org/10.5194/egusphere-egu22-982, 2022.

15:42–15:47
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EGU22-5120
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On-site presentation
Jan Jehlicka, Kateřina Němečková, and Adam Culka

Raman spectroscopy is an excellent tool for the detection and discrimination of biomolecules e.g. pigments. The highest relevance of Raman spectroscopy in astrobiology has been well-established. The miniaturized, dedicated Raman spectrometers are currently a part of the experimental payload within rovers in the frame of Martian missions Mars 2020 (NASA) and ExoMars (ESA). Finding biomolecules in the rocky environments (for example, detecting carotenoids) would be an amazing outcome of Mars missions. On Earth, semi-translucent or translucent minerals such as gypsum are ideal habitats for endoliths, especially phototrophs. The mineral environment participates in protecting them against harsh superficial environments. Cyanobacteria colonize gypsum, halite, ignimbrite in the Atacama extremely dry zones with high UV flux. Pigments of endoliths encountered there and detected using Raman spectroscopy include mainly UV-screening pigments such as carotenoids and scytonemin. Selenitic gypsum outcrops of Messinian age commonly harbour cyanobacteria and algae also in less harsh environments: in Sicily (annual precipitation 400-600 mm) [1], Poland (600 mm) and Northern Israel (400 mm). Details on the distribution of pigments (including scytonemin) from several gypsum sites in southern Sicily and eastern Poland are presented [2]. Raman investigations using 780, 532 and 445 nm lasers show more detail on the distribution of UV-screening pigments in the dark zones. These dark zones are colonized dominantly by cyanobacteria, mostly by black-bluish Gloeocapsa compacta and yellow-brown Nostoc sp. Raman analysis allows to discriminate between these cyanobacterial taxa. Raman bands of scytonemin at 1593, 1552, 1438 and 1173 cm-1 were detected in colonies of Nostoc sp. Gloeocapsin, a pigment specific for Gloeocapsa sp, shows characteristic Raman bands similar to anthraquinone-based parietin of lichens: at 1665, 1575, 1378, 1310 and 465 cm-1 [2]. Both pigments can be used as biomarkers in geobiological and astrobiological studies. Other photosynthetic and protective pigments were also detected: carotenoids, chlorophylls and phycobiliproteins. Deciphering the presence of biomolecules (including pigments) using Raman spectroscopy helps to understand endoliths. Deploying miniature Raman spectrometers at terrestrial Mars analogue localities as well as in depth investigations of colonised gypsum through laboratory microspectrometric investigations is of the highest relevance for the current Martian missions.

References

[1] J. Jehlička, A. Culka, J. Mareš, (2019) Raman spectroscopic screening of cyanobacterial chasmoliths from crystalline gypsum—The Messinian crisis sediments from Southern Sicily, Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy 51, 1802-1812. [2] K. Němečková, A. Culka, I. Němec, H.G.M. Edwards, J. Mareš, J. Jehlička (2021) Raman spectroscopic search for scytonemin and gloeocapsin in endolithic colonisations in large gypsum crystals. Journal of  Raman Spectroscopy 52, 2633-2647.

How to cite: Jehlicka, J., Němečková, K., and Culka, A.: Detecting Raman spectra of pigments from gypsum endoliths: is this a useful training for Martian missions?, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-5120, https://doi.org/10.5194/egusphere-egu22-5120, 2022.

15:47–15:52
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EGU22-12935
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ECS
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On-site presentation
Eleni Bohacek

The ExoMars Programme will send a rover to Mars in 2022 equipped with a 2 m drill which will search for evidence of extinct life below the surface. This project is focused on the stereo vision systems of the rover, and how better 3-D information can be extracted from the camera images. This is explored through both experimental and simulation-based approaches. The experimental approach was to build a hardware emulator of the three stereo pairs: the Wide-Angle Cameras (WACs) from the Panoramic Camera instrument (PanCam), and the Navigation Camera (NavCam) and Localisation Camera (LocCam) systems. Point clouds were generated from the emulator data and compared against a (LIDAR) generated point cloud to determine which combination of cameras yields the best point clouds. The comparison methods were as follows: the number of tie points, the number of dense cloud points, coordinate extent, surface density, nearest neighbour distance (NND) to the LIDAR cloud, and measurement of a known target. One set of experiments compared the four mast head stereo cameras (WACs and NavCams) and the second set compared all six stereo cameras (WACs, NavCams, and LocCams). The six-view point cloud was the closest match to the LIDAR in terms of mean NND to the LIDAR point cloud, but it was only marginally better than the five-view point clouds and the four-view point cloud made of the WACs and NavCams. The conclusions from both sets of experiments are that the three stereo camera pairs do not contribute equally to improvements in the point clouds generated through photogrammetry. The emulator WACs are the most suited to photogrammetric reconstruction, followed by the emulator NavCams and finally the emulator LocCams.

How to cite: Bohacek, E.: The 3-D capability of science and engineering cameras on the ExoMars rover, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12935, https://doi.org/10.5194/egusphere-egu22-12935, 2022.

15:52–15:57
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EGU22-4033
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On-site presentation
Stephan Ulamec, Patrick Michel, Matthias Grott, Ute Böttger, Heinz-Willhelm Hübers, Yuichiro Cho, Fernando Rull, Naomi Murdoch, Pierre Vernazza, Jens Biele, Simon Tardivel, and Hirdy Miyamoto

The Mars Moon eXploration (MMX) mission by the Japan Aerospace Exploration Agency, JAXA, which is going to explore the Martian Moons Phobos and Deimos and also return samples from Phobos back to Earth will also deliver a small (about 25 kg) Rover to the surface of Phobos.

The payload of this rover consists of a Raman spectrometer (RAX) to measure the mineralogical composition of the surface material, a stereo pair of cameras looking affront (NavCam, also used for navigation) to provide the properties of the investigated area, a radiometer (miniRAD) to measure the surface brightness temperature and determine thermal properties of both regolith and rocks, and two cameras looking at the wheel-surface interface (WheelCam) to investigate the properties and dynamics of the regolith. The cameras will, thus, serve for both, technological and scientific needs.
After the Rover has been delivered by the main spacecraft, it shall upright itself and operate for about 100 days on the surface of Phobos to investigate terrain and mineralogy along its path.
The measurements are going to provide ground truth by studying in-situ properties such as the physical properties and heterogeneity of the surface material.

MMX is planned to be launched in September 2024, the Rover delivery is currently planned for 2027.
The Rover is a contribution by the Centre National d’Etudes Spatiales (CNES) and the German Aerospace Center (DLR) with additional contributions from INTA (Spain) and JAXA.

How to cite: Ulamec, S., Michel, P., Grott, M., Böttger, U., Hübers, H.-W., Cho, Y., Rull, F., Murdoch, N., Vernazza, P., Biele, J., Tardivel, S., and Miyamoto, H.: Phobos Surface Science with the MMX Rover, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-4033, https://doi.org/10.5194/egusphere-egu22-4033, 2022.

15:57–16:02
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EGU22-6333
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Highlight
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On-site presentation
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Dmitrij Titov, Colin Wilson, Jean-Pierre Bibring, Alejandro Cardesin, John Carter, Tom Duxbury, Francois Forget, Marco Giuranna, Francisco González-Galindo, Mats Holmström, Ralf Jaumann, Anni Määttänen, Patrick Martin, Franck Montmessin, Roberto Orosei, Martin Pätzold, Jeff Plaut, and Mex Sgs Team

After 18 years in orbit Mars Express remains one of ESA’s most scientifically productive Solar System missions, with a publication record now exceeding 1450 papers. Characterization of the surface geology on a local-to-regional scale by HRSC, OMEGA and partner experiments on NASA spacecraft has allowed constraining land-forming processes in space and time. Recent studies characterized the geology of Jezero crater in great detail and provided Digital Elevation Model (DEM) of several equatorial regions at 50 m/px resolution. New maps and catalogues of surface minerals with 200 m/px resolution were released. MARSIS radar published new observations and analysis of the multiple subglacial water bodies underneath the Southern polar cap. Modelling suggested that the “ponds” can be composed of hypersaline perchlorate brines.

Spectrometers and imagers SPICAM, PFS, OMEGA, HRSC and VMC continue adding to the longest record of atmospheric parameters such as temperature, dust loading, water vapor and ozone abundance, water ice and CO2 clouds distribution and observing transient phenomena. More than 27,000 ozone profiles derived from SPICAM UV spectra obtained in MY#26 through MY#28 were assimilated in the OpenMARS database. A new PFS “scan” mode of the spacecraft was designed and implemented to investigate diurnal variations of the atmospheric parameters. Observations of Tharsis region and Hellas basin contribute to mesoscale meteorology.

ASPERA measurements together with MAVEN “deep dip” data enabled assessment of the conditions that lead to the formation of the dayside ionopause in the regions with and without strong crustal magnetic fields suggesting that the ionopause occurs where the total ionospheric pressure (magnetic + thermal) equals the upstream solar wind dynamic pressure.

In 2021 Mars Express successfully performed two types of novel observations. In egress-only radio-occultations a two-way radio link was locked at a tangent altitude of about 50 km. This is well below the ionospheric peak and would allow perfect sounding of the entire ionosphere thus doubling the number of ionospheric soundings. MEX and TGO performed several test UHF occultations. The dual-spacecraft radio-occultation technique would allow much broader spatial distribution of the missions’ radio occultation profiles.  

Mars Express is extended till the end of 2022. A science case for the mission extension till the end of 2025 will be developed and submitted in March 2022. The talk will give the Mars Express status, review the recent science highlights, and outline future plans including synergistic science with TGO and other missions.

How to cite: Titov, D., Wilson, C., Bibring, J.-P., Cardesin, A., Carter, J., Duxbury, T., Forget, F., Giuranna, M., González-Galindo, F., Holmström, M., Jaumann, R., Määttänen, A., Martin, P., Montmessin, F., Orosei, R., Pätzold, M., Plaut, J., and Sgs Team, M.: Mars Express science highlights and future plans, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6333, https://doi.org/10.5194/egusphere-egu22-6333, 2022.

16:02–16:40
Coffee break
Chairperson: Maria Hieta
17:00–17:02
17:02–17:07
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EGU22-1708
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On-site presentation
Jaroslav Klokocnik, Gunther Kletetschka, Jan Kostelecky, Ales Bezdek, and Kurosh Karimi

A search for water on Mars is an important part of a space program. Water is likely to be contained not only in the polar caps but also deposited further away from the polar regions, specifically in the so called “fretted terrain” (near dichotomy boundary between the lowlands and highlands), in the northern lowlands, and elsewhere.  Here we attempt to reconstruct a northern paleo-ocean, using the gravity aspects and locations of features of the fretted terrain as constraints for paleo-seashore. Valles Marineris would contain water that would flow into this ocean. We use recent data on the gravity and magnetic fields of Mars and create from them the gravity aspects and magnetic field proxies computed from the recent gravity and magnetic models JGMRO_120F (Konopliv et al., 2020) and (Connerney et al., 2005; Langlais et al., 2019). We discovered that Isidis, based on gravity aspects, has many volcano-like characteristics despite the traditional view of this structure being an impact related. We note asymmetric positions of Martian polar caps that seem to be related to the magnetic field distribution and we propose a new hypothesis that polar cap accumulation relates to a plasmasphere interaction with the solar wind.  Analysis of the detection of direction of the impactor arrival for Hellas impact basin along with the gravity aspects (namely the strike angles) suggested  that not only the impact likely generated a reset of the global plum activity (that changed the overall unicellular convection pattern into the bicellular convection) but also note the possibility that the magnetic maxima in the polar region could be paleoindicators of the offset by this impact event so that the rotational poles have an offset from the magnetic poles.

 

How to cite: Klokocnik, J., Kletetschka, G., Kostelecky, J., Bezdek, A., and Karimi, K.: Gravity and magnetic fields of Mars - new findings, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-1708, https://doi.org/10.5194/egusphere-egu22-1708, 2022.

17:07–17:12
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EGU22-12428
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Virtual presentation
sebastien Le Maistre, Attilio Rivoldini, Alfonso Caldiero, Marie Yseboodt, Rose-Marie Baland, Mikael Beuthe, Tim Van Hoolst, Veronique Dehant, William Folkner, Dustin Buccino, Daniel Kahan, Jean-Charles Marty, Daniele Antonangeli, James Badro, Melanie Drilleau, Alex Konopliv, Marie-Julie Peters, Ana-Catalina Plesa, Henri Samuel, and Nicola Tosi and the InSight/RISE team

We report here the results of more than 2 years of monitoring the rotation of Mars with the RISE instrument on InSight. Small periodic variations of the spin axis orientation, called nutations, can be extracted from the Doppler data with enough precision to identify the influence of the Martian fluid core.  For the first time for a planetary body other than the Earth, we can measure the period of the Free Core Nutation (FCN), which is a rotational normal mode arising from the misalignment of the rotation axes of the core and mantle. In this way, we confirm the liquid state of the core and estimate its moment of inertia as well as its likely size.

The FCN period depends on the dynamical flattening of the core and on its ability to deform. Since the shape and gravity field of Mars deviate significantly from those of a uniformly rotating fluid body, deviations from that state can also be expected for the core. Models accounting for the dynamical shape of Mars can thus be tested by comparing core shape predictions to nutation constraints. The observed FCN period can be accounted for by interior models having a very thick lithosphere loaded by degree-two mass anomalies at the bottom.

The combination of nutation data and interior structure modeling allows us to deduce the radius of the core and to constrain its density, and thus, to address the nature and abundance of light elements alloyed to iron. The inferred core radius agrees with previous estimates based on geodesy and seismic data. The large fraction of light elements required to match the core density implies that its liquidus is significantly lower than the expected core temperature, making the presence of an inner core highly unlikely. Besides, the existence of an inner core would lead to an additional rotational normal mode the signature of which has not been detected in the RISE data.

How to cite: Le Maistre, S., Rivoldini, A., Caldiero, A., Yseboodt, M., Baland, R.-M., Beuthe, M., Van Hoolst, T., Dehant, V., Folkner, W., Buccino, D., Kahan, D., Marty, J.-C., Antonangeli, D., Badro, J., Drilleau, M., Konopliv, A., Peters, M.-J., Plesa, A.-C., Samuel, H., and Tosi, N. and the InSight/RISE team: The deep interior of Mars from nutation measured by InSight RISE, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12428, https://doi.org/10.5194/egusphere-egu22-12428, 2022.

17:12–17:17
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EGU22-7888
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On-site presentation
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Maria Hieta, Jouni Polkko, Iina Jaakonaho, Maria Genzer, Shahin Tabandeh, José Antonio Rodríguez Manfredi, Leslie Tamppari, and Manuel de la Torre Juarez

MEDA HS is the relative humidity sensor on the Mars 2020 Perseverance rover provided by the Finnish Meteorological Institute (FMI). The sensor is a part of Mars Environmental Dynamic Analyzer (MEDA), a suite of environmental sensors provided by Centro de Astrobiología in Madrid, Spain.

The accuracy requirement for MEDA HS relative humidity was ±10% RH for temperatures above -70 ºC, and ±20% RH for temperatures between -83...-73 ºC. Dynamic range from 0 to 100% RH shall cover the whole Martian temperature range from -83 ºC to -3 ºC. However it must be noted that during the daytime when the relative humidity drops close to zero, the readings are not scientifically meaningful due to the large relative uncertainty.

MEDA HS flight model was tested and calibrated in Mars-like dry environment at FMI together with flight spare and ground reference models from +22 ºC to -70 ºC and in saturation conditions from -40 ºC down to -70 ºC. Further, the MEDA HS flight model final calibration is complemented by calibration data transferred from an identical ground reference model which has gone through extensive humidity calibration test campaign at DLR PASLAB. The MEDA HS has been calibrated to full relative humidity range between -70 to -40 ºC in CO2 in the pressure ranges from 5.5 to 9.5 hPa, representative of Martian surface atmospheric pressure, and partial range up to +22 ºC. For lower temperatures the results are extrapolated.

The complex analysis of the MEDA HS measurement uncertainty has now been finalized and the results are presented in the conference. It has been found that the sensor exceeds the design requirements and will provide high accuracy relative humidity measurements from the Martian surface to provide important meteorological observations and to support MEDA and other M2020 investigations.

How to cite: Hieta, M., Polkko, J., Jaakonaho, I., Genzer, M., Tabandeh, S., Rodríguez Manfredi, J. A., Tamppari, L., and de la Torre Juarez, M.: Accuracy of the relative humidity sensor MEDA HS onboard Perseverance rover, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7888, https://doi.org/10.5194/egusphere-egu22-7888, 2022.

17:17–17:22
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EGU22-5796
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On-site presentation
Agustin Sanchez-Lavega, Teresa del Rio-Gaztelurrutia, Ricardo Hueso, Manuel de la Torre, Ari-Matti Harri, Maria Genzer, Maria Hieta, Jouni Polkko, José Antonio Rodríguez-Manfredi, Leslie K. Tamppari, Claire Newman, Asier Munguira, Germán Martínez, Alvaro Vicente-Retortillo, Mark Lemmon, Jorge Pla-Garcia, Scott Guzewich, Daniel Toledo, Víctor Apéstigue, and Daniel Viúdez-Moreiras and the Additional Team members

We report the analysis of pressure measurements at Jezero crater, Mars by the MEDA instrument [1] onboard the rover Perseverance following its landing and covering the period from March 5, 2021 up to this meeting presentation (approximately from solar longitudes 15° to 200°). We identify a variety of atmospheric phenomena, spanning from local to global spatial and temporal scales that leave their imprint in the pressure data [2]. These comprises: Local turbulence (high frequency fluctuations), waves (short period oscillations 12-24 minutes), local vortices (sudden pressure drops from seconds to a minute), baroclinic waves (oscillation periods 4-5 sols) and up to six Fourier components of the thermal tides. The normalized amplitude of the diurnal and semidiurnal tides show a large variability along the studied period, but smaller changes are also noted in tidal components 3 to 6.  We report on the effects of the presence of water ice clouds and dust from storms on the tidal components. Finally, we present the main parameters that characterize each of the phenomena studied, their variability throughout this period, and a preliminary interpretation for all of them.

References:

[1] Rodríguez-Manfredi J. A. et al., Space Sci. Rev., 217.3, 1-86 (2021)

[2] Sánchez-Lavega A. et al., Perseverance/Mars2020 measurements of the daily pressure cycle at Jezero, P25A-03, AGU Fall Meeting (2021)

How to cite: Sanchez-Lavega, A., del Rio-Gaztelurrutia, T., Hueso, R., de la Torre, M., Harri, A.-M., Genzer, M., Hieta, M., Polkko, J., Rodríguez-Manfredi, J. A., Tamppari, L. K., Newman, C., Munguira, A., Martínez, G., Vicente-Retortillo, A., Lemmon, M., Pla-Garcia, J., Guzewich, S., Toledo, D., Apéstigue, V., and Viúdez-Moreiras, D. and the Additional Team members: Weather at Jezero, Mars from pressure measurements by the rover Perseverance, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-5796, https://doi.org/10.5194/egusphere-egu22-5796, 2022.

17:22–17:27
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EGU22-6325
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Virtual presentation
Daniel Viúdez-Moreiras, Claire E. Newman, Javier Gómez-Elvira, Ari-Matti Harri, María Genzer, Leslie Tamppari, Manuel de la Torre, Agustín Sánchez, Ricardo Hueso, Scott Guzewich, Rob Sullivan, Jorge Pla, Sara Navarro, Asier Munguira, Ralph Lorenz, Kenneth Herkenhoff, Jose Antonio Rodríguez-Manfredi, and the MEDA team

NASA’s Mars 2020 Perseverance rover landed in Jezero Crater (~18.4ºN, 77.6ºE) on February 2021 at Ls~5º, just after the northern spring equinox. Perseverance carries the Mars Environmental Dynamics Analyzer (MEDA) instrument [1], which includes a wind sensor that is a heritage from previous sensors sent to Mars as part of the Mars Science Laboratory (MSL) and InSight missions. Those sensors allowed the characterization of the near-surface wind patterns at Gale Crater [2] and Elysium Planitia [3,4]. The wind sensor of MEDA is allowing near-surface wind patterns to be characterized at Perseverance’s landing site, thus complementing the data acquired by previous missions on the surface of Mars.

Previous missions at different locations on the Martian surface observed a contribution by several mechanisms from different scales involved in the near-surface winds, including the effect of local and regional slope winds induced by topography, thermal tides, baroclinic waves and the Hadley cell, each one with a variable weight on the resulting wind patterns as a function of location, season and the presence of dust storms (e.g. [2-4] and references therein). The near-surface wind data acquired by Mars 2020 show a complex dynamics at Jezero Crater, as predicted by models (e.g. [5]). Preliminary interpretation suggests that the diurnal cycle of winds is dominated by the regional circulation mainly forced by slope winds in the Isidis basin region, which interact with the local scale circulation at Jezero and Hadley cell flows. The potential contribution by these mechanisms on the resulting wind patterns measured at Mars2020’s landing site will be presented, with a further focus on the observed wind variability supported by probabilistic models.

 

References:

[1] Rodriguez-Manfredi et al. (2021), SSR, 217(48). [2] Viúdez-Moreiras et al. (2019), Icarus, 319, 909-925. [3] Banfield et al. (2020), Nat.Geo, 13, 190-198. [4] Viúdez-Moreiras et al. (2020) JGR-Planets, 125, e2020JE006493. [5] Newman et al. (2021) SSR, 217(20).

How to cite: Viúdez-Moreiras, D., Newman, C. E., Gómez-Elvira, J., Harri, A.-M., Genzer, M., Tamppari, L., de la Torre, M., Sánchez, A., Hueso, R., Guzewich, S., Sullivan, R., Pla, J., Navarro, S., Munguira, A., Lorenz, R., Herkenhoff, K., Rodríguez-Manfredi, J. A., and MEDA team, T.: The near-surface wind patterns as observed by NASA Mars 2020 Mission at Jezero Crater, Mars, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6325, https://doi.org/10.5194/egusphere-egu22-6325, 2022.

17:27–17:32
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EGU22-7047
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ECS
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On-site presentation
Asier Munguira, Ricardo Hueso, Agustín Sánchez-Lavega, Manuel de la Torre-Juarez, Ángel Chavez, Germán Martínez, Claire Newman, Donald Banfield, Álvaro Vicente-Retortillo, Alain Lepinette, Jorge Pla-García, Jose Antonio Rodríguez-Manfredi, Baptiste Chide, Tanguy Bertrand, Eduardo Sebastián, Javier Gómez-Elvira, Mark Lemmon, Leslie Tamppari, Ralph Lorenz, and Daniel Viudez-Moreiras and the additional MEDA team members

The Mars Environmental Dynamics Analyzer (MEDA) is a meteorological station onboard Mars 2020 that characterizes the near surface atmosphere. Among other sensors MEDA has 5 Air Temperature Sensors (ATS) at two altitudes: 0.85m, in the front of the rover, and 1.45m around the Remote Sensing Mast, which are azimuthally distributed so that at least one sensor is located upwind. This configuration ensures that, for most environmental conditions, the thermal contamination caused by the rover can be set apart. Local air temperatures are read with a frequency of 1 or 2 Hz, and ATS data can characterize timescales from atmospheric turbulence to the daily temperature cycle and its seasonal evolution. 

Here we show the daily temperature cycle at Jezero and an analysis of its seasonal evolution over the first half Martian year of the mission from Spring (Ls=6) to Autumn Equinox (Ls=180). Simultaneous ATS and winds from MEDA’s wind sensors show that, for most rover orientations, solar irradiation and winds clean environmental measurements are obtained at the 1.45m level. However, clean measurements at the 0.85m level are not always fully achieved, and a small residual thermal contamination is found at this level in many measurement sessions. The daily temperature cycle reflects the daily cycle of convection and turbulence. Strong and fast thermal oscillations start a few hours after sunrise, peak near noon, and collapse before sunset. The seasonal evolution shows a progressive increase of temperatures as summer advances, but less steep than what is retrieved at other Martian locations by previous missions. At the 0.85m level, changes in atmospheric temperatures with time-scales of a few sols correlate well with variations in local terrain properties. At the 1.45m level, similar temperature changes with timescales of a few sols are also found. We investigate whether these changes at 1.45m can be associated with changing atmospheric opacity due to dust and clouds, which are measured by other MEDA sensors and additional instruments in Perseverance. From the two altitudes sampled with ATS, and additional data from the MEDA Thermal InfraRed Sensors (TIRS), which measure ground temperature and air temperature at 40m, we can obtain the near-surface vertical temperature profile for specific sols in which thermal contamination is moderate in all sensors. This allows us to study the evolution of the diurnal convective cycle and the vertical temperature gradient. In addition, the Supercam microphone can also deduce the average air temperature from the ground up to 2.1m high thanks to sound speed measurements during Supercam’s laser zapping rocks. Therefore, it gives an additional hint into the thermal gradient. Furthermore, the amplitude of the thermal oscillations characterizes the thermal turbulence and we present the spectra of turbulence for convective and non convective hours on different moments of the mission. Finally, we will show how the measured thermal data compares with model predictions of the daily cycle of temperatures, expected magnitude of thermal oscillations, and the seasonal evolution.



How to cite: Munguira, A., Hueso, R., Sánchez-Lavega, A., de la Torre-Juarez, M., Chavez, Á., Martínez, G., Newman, C., Banfield, D., Vicente-Retortillo, Á., Lepinette, A., Pla-García, J., Rodríguez-Manfredi, J. A., Chide, B., Bertrand, T., Sebastián, E., Gómez-Elvira, J., Lemmon, M., Tamppari, L., Lorenz, R., and Viudez-Moreiras, D. and the additional MEDA team members: Mars 2020 MEDA ATS Measurements of Near Surface Atmospheric Temperatures at Jezero, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7047, https://doi.org/10.5194/egusphere-egu22-7047, 2022.

17:32–17:37
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EGU22-11769
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ECS
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On-site presentation
Jesper Henneke, David A. K. Pedersen, John Leif Jørgensen, Yang Liu, Abigail C. Allwood, Joel Hurowitz, Mariek E. Schmidt, and Scott J. VanBommel

The Planetary Instrument of X-ray Lithochemistry (PIXL), onboard the Mars 2020 rover Perseverance, is designed to measure the chemical composition of Martian materials with a spatial resolution of around 100 µm. The surface of Mars is notoriously dusty and even thin layers of dust within the measurement frame will impact the instrument signal, potentially leading to misinterpretation of an underlying chemical composition if not appropriately accounted for. Therefore, knowledge about the dust composition, concentration and distribution is important, both when deciding where to perform measurements and in data analyses.

Herein we present methods for generating high precision dust profiles of Martian surfaces by utilizing the Optical Fiducial System (OFS) component of the PIXL instrument. The OFS consist of a Micro Context Camera (MCC) and a FloodLight Illuminator (FLI). The MCC captures images with a resolution better than 50 µm/pixel at the instrument’s nominal distance of 25 mm, directly enabling the optical characterization of dust, and other components, on these surfaces. The FLI is equipped with a total of 24 light emitting diodes (LEDs), in four groups centered at UV (385 nm), Blue (450 nm), Green (530 nm), and NIR (735 nm), enabling multispectral capabilities. This multispectral floodlight capability directly facilitates dust detection by the MCC, and utilizing the precision of the MCC, the spatial distribution of dust is better constrained.

We present dust profile maps acquired by the PIXL OFS on Martian surfaces and present similar results derived from the rover-mounted calibration targets. In demonstrating the quality of the maps produced, we can improve future scientific analyses while furthermore improving the operational efficiency and data quality of the Perseverance mission through the potential future implementation of a closed-loop autonomous dust-avoidance routine, utilizing the macro capabilities of the PIXL OFS.

 

The author recognises the great contribution made by the PIXL Team and the broader Mars 2020 Team.

How to cite: Henneke, J., Pedersen, D. A. K., Jørgensen, J. L., Liu, Y., Allwood, A. C., Hurowitz, J., Schmidt, M. E., and VanBommel, S. J.: Profiling Martian Dust Using PIXL Images, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-11769, https://doi.org/10.5194/egusphere-egu22-11769, 2022.

17:37–17:42
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EGU22-11234
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ECS
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Presentation form not yet defined
David Pedersen, Jesper Henneke, John Leif Jørgensen, Mathias Benn, Troelz Denver, Lars Timmermann, Carl Christian Liebe, Robert Denise, Tim Elam, Lawrence Wade, Marc Foote, Joel Hurowitz, and Abigail Allwood

The Micro Context Camera (MCC) of PIXL onboard Perseverance has successfully completed commissioning. It meets all requirements and has led to the first proximity science using the PIXL instrument. This abstract presents the inflight system performance.

The pre-launch calibration of the MCC system has been verified on the surface of Mars. Distance measurements to Martian Rock surfaces are performed at with an accuracy better than 100 µm. This is accomplished utilizing Structured Light over the full diurnal thermal environment on the surface of Mars. The PIXL sensor unit is mounted on the turret of the Mars Perseverance rover arm. This autonomous navigation capability has enabled safe approaches of rugged surfaces, without ground intervention or interaction with e.g. a touch plate. It has also enabled proximity science of the Martian surface at unprecedented accuracy. The autonomy further enables PIXL to capture high resolution XRF scans while continuously maintaining optimal distance and focus of the X-ray beam. The system’s performance is robust enough for PIXL to navigate relative to both abraded and natural surfaces.

The MCC also has the capability of multispectral imaging. This has provided information for the interpretation of surface lithology and it also provides additional information for the XRF measurements interpretation due to its high resolution.

The MCC’s Terrain Relative Navigation (TRN) autonomous functionality has also been demonstrated in the Martian environment. This capability is essential for PIXL to maintain the planned scan trajectory relative to the rock surface – as PIXL’s longer duration scans (up to 10 hours) is relying on stability and capability to compensate for the diurnal thermal environment causing position drift relative to the Martian rock surface. We present the measured performance on Mars. This show that the system performs reliably on both high and low topography rock surfaces with and without dust coverage. This has enabled PIXL to autonomously track and self-correct for any drift away from the planned scan trajectory.

How to cite: Pedersen, D., Henneke, J., Jørgensen, J. L., Benn, M., Denver, T., Timmermann, L., Liebe, C. C., Denise, R., Elam, T., Wade, L., Foote, M., Hurowitz, J., and Allwood, A.: PIXL’s Micro Context Camera performance on the surface of Mars, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-11234, https://doi.org/10.5194/egusphere-egu22-11234, 2022.

17:42–17:47
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EGU22-5969
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Virtual presentation
Cathy Quantin-Nataf, Lucia Mandon, Clement Royer, Pierre Beck, Frank Montmessin, Olivier Forni, Stephane Le Mouelic, François Poulet, Jeffrey Johnson, Thierry Fouchet, Erwin Dehouck, Adrian Brown, Jesse Tarnas, Paolo Pilleri, Olivier Gasnault, Nicolas Mangold, Sylvestre Maurice, and Roger Wiens

On February 18, 2021, NASA’s Mars 2020 Perseverance rover landed successfully in Jezero crater. Several geological and compositional units were previously identified from orbital data analysis : a dark pyroxene-bearing floor unit; an olivine-bearing unit exposed in erosional windows and partially altered into phyllosilicates and carbonates ; a deltaic complex and its possible erosional remnants and a marginal carbonate-bearing unit. As of Sol 300 (December 2021), the rover has visited two geological units in situ: the dark pyroxene-bearing floor unit and the olivine-bearing floor unit. Others investigations of geological units of interest have been carried out using long distance (up to several kilometers) observations.

The SuperCam instrument contains a suite of techniques including passive spectroscopy in the 0.40-0.85 (VIS) and 1.3-2.6 microns (IR) wavelength ranges, and a color camera (RMI- Remote Micro-Imager) providing high resolution context images. Since the landing, SuperCam has acquired thousands of VISIR spectra of nearby rocks (including both natural and abraded surfaces), as well as hundreds of spectra of distant targets (from 10s of m to 20 km). The VISIR field of view of each individual spectrum ranges from a few mm for the rock of the workspace to 20 m to 20 km. The aim of this contribution is to summarize the main results of VISIR spectra up to Sol 300.

The two geological units investigated in situ have distinct spectra. The crater floor rough unit (Cf-fr)  has a pervasive 1.9 µm absorption indicative of hydration. Additional absorption at 2.28 µm indicate the presence of iron-rich phyllosilicates. Correlations between 1.9 µm and 2.4 µm absorption bands or between 2.1 µm and 2.4 µm bands suggest the presence of both poly and monohydrated sulfates. Spectra similar to oxy-hydroxides have also been observed in some rocks. Unmixing methods such as factor analyses highlight a high calcium pyroxene component. To sum up, the Cf-fr is an altered pyroxene rich unit. The second unit investigated in situ is a region called Seitah, which is dominantly olivine-rich from orbital analyses. Supercam VISIR data confirm the strong signature of olivine of the unit and display a complex suite of absorptions in the 2.3 µm - 2.4 µm region suggesting the presence of iron and magnesium phyllosilicates and/or carbonates. The alteration signature seems to be associated with olivine grains. 

Distant observations were acquired on the western delta front, several remote mesas and hills, on Jezero floor unit (the unit on which Perseverance landed on and investigated in situ), on Seitah before being visited by the rover, and on even more distant targets such as the crater rim or the marginal carbonate-bearing unit. The observed spectral signatures form different clusters depending on the type of target, highlighting the spectral diversity of Jezero geological units.  Remarkably, the long distance observations of Seitah region are in perfect agreement with the in situ measurements confirming the relevance of long distance observations to assess the geological/mineralogical context of Perseverance’s future traverses.

How to cite: Quantin-Nataf, C., Mandon, L., Royer, C., Beck, P., Montmessin, F., Forni, O., Le Mouelic, S., Poulet, F., Johnson, J., Fouchet, T., Dehouck, E., Brown, A., Tarnas, J., Pilleri, P., Gasnault, O., Mangold, N., Maurice, S., and Wiens, R.: Infrared Reflectance of Jezero geological units from Supercam/Mars2020 Observations, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-5969, https://doi.org/10.5194/egusphere-egu22-5969, 2022.

17:47–18:17