No detection of methane on Mars from early ExoMars Trace Gas Orbiter observations

The detection of methane on Mars has been interpreted as indicating that geochemical or biotic activities could persist on Mars today. A number of different measurements of methane show evidence of transient, locally elevated methane concentrations and seasonal variations in background methane concentrations. These measurements, however, are difficult to reconcile with our current understanding of the chemistry and physics of the Martian atmosphere, which-given methane's lifetime of several centuries-predicts an even, well mixed distribution of methane. Here we report highly sensitive measurements of the atmosphere of Mars in an attempt to detect methane, using the ACS and NOMAD instruments onboard the ESA-Roscosmos ExoMars Trace Gas Orbiter from April to August 2018. We did not detect any methane over a range of latitudes in both hemispheres, obtaining an upper limit for methane of about 0.05 parts per billion by volume, which is 10 to 100 times lower than previously reported positive detections. We suggest that reconciliation between the present findings and the background methane concentrations found in the Gale crater would require an unknown process that can rapidly remove or sequester methane from the lower atmosphere before it spreads globally

Martian dust storm impact on atmospheric H₂O and D/H observed by ExoMars Trace Gas Orbiter

Global dust storms on Mars are rare but can affect the Martian atmosphere for several months. They can cause changes in atmospheric dynamics and inflation of the atmosphere, primarily owing to solar heating of the dust. In turn, changes in atmospheric dynamics can affect the distribution of atmospheric water vapour, with potential implications for the atmospheric photochemistry and climate on Mars. Recent observations of the water vapour abundance in the Martian atmosphere during dust storm conditions revealed a high-altitude increase in atmospheric water vapour that was more pronounced at high northern latitudes, as well as a decrease in the water column at low latitudes. Here we present concurrent, high-resolution measurements of dust, water and semiheavy water (HDO) at the onset of a global dust storm, obtained by the NOMAD and ACS instruments onboard the ExoMars Trace Gas Orbiter. We report the vertical distribution of the HDO/H O ratio (D/H) from the planetary boundary layer up to an altitude of 80 kilometres. Our findings suggest that before the onset of the dust storm, HDO abundances were reduced to levels below detectability at altitudes above 40 kilometres. This decrease in HDO coincided with the presence of water-ice clouds. During the storm, an increase in the abundance of H2O and HDO was observed at altitudes between 40 and 80 kilometres. We propose that these increased abundances may be the result of warmer temperatures during the dust storm causing stronger atmospheric circulation and preventing ice cloud formation, which may confine water vapour to lower altitudes through gravitational fall and subsequent sublimation of ice crystals. The observed changes in H2O and HDO abundance occurred within a few days during the development of the dust storm, suggesting a fast impact of dust storms on the Martian atmosphere

How to Set Up a Research Framework to Analyze Social-Ecological Interactive Processes in a Rural Landscape

Interdisciplinary research frameworks can be useful in providing answers to the environmental challenges facing rural environments, but concrete implementation of them remains empirical and requires better control. We present our practical experience of an interdisciplinary research project dealing with non-industrial private forestry in rural landscapes. The theoretical background, management, and methodological aspects, as well as results of the project, are presented in order to identify practical key factors that may influence its outcomes. Landscape ecology plays a central role in organizing the project. The efforts allocated for communication between scientists from different disciplines must be clearly stated in order to earn reciprocal trust. Sharing the same nested sampling areas, common approaches, and analytical tools (GIS) is important, but has to be balanced by autonomy for actual implementation of field work and data analysis in a modular and evolving framework. Data sets are at the heart of the collaboration and GIS is necessary to ensure their long-term management and sharing. The experience acquired from practical development of such projects should be shared more often in networks of teams to compare their behavior and identify common rules of functioning

Expected first results from the SuperCam microphone onboard the NASA Perseverance rover

International audienceThe NASA Perseverance rover will land on Mars in February 2021, bringing with it a new suite of analytical instruments with which to explore its landing site in Jezero crater. The primary goal of this new mission is to assess the geology and past habitability in order to identify and cache samples with a high likelihood of preserving biosignatures, in preparation for a future sample return mission [1]. As part of its instrument payload, Perseverance will carry the SuperCam instrument [2-3]. SuperCam combines a number of analytical techniques, notably a laser-induced breakdown spectroscopy (LIBS) instrument for chemical analysis that is coupled with a microphone for acoustic studies. The SuperCam microphone is a commercial of-the-shelf electret (based on Knowles EK-23132) and is designed to record sounds in the audible range, from 100 Hz to 10 kHz, during the surface mission. There are three main science investigations of interest for the SuperCam microphone: 1) Analysis of the LIBS acoustic signal; 2) study of atmospheric phenomena; and 3) examination of rover mechanical sounds. Since the atmosphere will be the source of acoustic signals, the microphone may be used to better understand the nature of the atmosphere and related phenomena such as thermal gradient and convective behavior in the rover"s vicinity [4], the behavior of dust devils [5], and to refine current atmospheric attenuation models for Mars [6]. Under atmosphere, LIBS analysis produces an acoustic signal due to the creation of a shock wave during laser ablation of a target. This acoustic signal can provide critical information about a target"s hardness and ablation depth [7-8] and whether there are coatings or thin layers present [9]. Mechanisms on the rover itself will also provide a source of acoustic signal that may be examined by the SuperCam microphone, notably sounds produced by the Mars Oxygen ISRU Experiment (MOXIE, [10]) instrument pumps during oxygen production. By the time of the conference, the SuperCam microphone should have acquired the first sounds on Mars; we will report on these exciting initial results and compare them to our prelanding expectations.[1] Farley K.A. et al. (2020) SSR 216, 142. [2] Wiens R.C. et al. (2021) SSR 217(4). [3] Maurice, S. et al. (in revision) SSR. [4] Chide, B. et al. (2020) 52nd LPSC. [5] Murdoch, N. et al. (2021) 52nd LPSC. [6] Chide, B. et al. (2020) AGU Fall meeting, S007-02. [7] Chide, B. et al. (2019) SAB 153, 50-60. [8] Chide, B. et al. (2020) SAB 174, 106000. [9] Lanza, N.L. et al (2020) 51st LPSC, no. 2807. [10] Hecht, M. H. et al. (2015) 46th LPSC, no. 2774

Expected first results from the SuperCam microphone onboard the NASA Perseverance rover

International audienceThe NASA Perseverance rover will land on Mars in February 2021, bringing with it a new suite of analytical instruments with which to explore its landing site in Jezero crater. The primary goal of this new mission is to assess the geology and past habitability in order to identify and cache samples with a high likelihood of preserving biosignatures, in preparation for a future sample return mission [1]. As part of its instrument payload, Perseverance will carry the SuperCam instrument [2-3]. SuperCam combines a number of analytical techniques, notably a laser-induced breakdown spectroscopy (LIBS) instrument for chemical analysis that is coupled with a microphone for acoustic studies. The SuperCam microphone is a commercial of-the-shelf electret (based on Knowles EK-23132) and is designed to record sounds in the audible range, from 100 Hz to 10 kHz, during the surface mission. There are three main science investigations of interest for the SuperCam microphone: 1) Analysis of the LIBS acoustic signal; 2) study of atmospheric phenomena; and 3) examination of rover mechanical sounds. Since the atmosphere will be the source of acoustic signals, the microphone may be used to better understand the nature of the atmosphere and related phenomena such as thermal gradient and convective behavior in the rover"s vicinity [4], the behavior of dust devils [5], and to refine current atmospheric attenuation models for Mars [6]. Under atmosphere, LIBS analysis produces an acoustic signal due to the creation of a shock wave during laser ablation of a target. This acoustic signal can provide critical information about a target"s hardness and ablation depth [7-8] and whether there are coatings or thin layers present [9]. Mechanisms on the rover itself will also provide a source of acoustic signal that may be examined by the SuperCam microphone, notably sounds produced by the Mars Oxygen ISRU Experiment (MOXIE, [10]) instrument pumps during oxygen production. By the time of the conference, the SuperCam microphone should have acquired the first sounds on Mars; we will report on these exciting initial results and compare them to our prelanding expectations.[1] Farley K.A. et al. (2020) SSR 216, 142. [2] Wiens R.C. et al. (2021) SSR 217(4). [3] Maurice, S. et al. (in revision) SSR. [4] Chide, B. et al. (2020) 52nd LPSC. [5] Murdoch, N. et al. (2021) 52nd LPSC. [6] Chide, B. et al. (2020) AGU Fall meeting, S007-02. [7] Chide, B. et al. (2019) SAB 153, 50-60. [8] Chide, B. et al. (2020) SAB 174, 106000. [9] Lanza, N.L. et al (2020) 51st LPSC, no. 2807. [10] Hecht, M. H. et al. (2015) 46th LPSC, no. 2774

Expected first results from the SuperCam microphone onboard the NASA Perseverance rover

International audienceThe NASA Perseverance rover will land on Mars in February 2021, bringing with it a new suite of analytical instruments with which to explore its landing site in Jezero crater. The primary goal of this new mission is to assess the geology and past habitability in order to identify and cache samples with a high likelihood of preserving biosignatures, in preparation for a future sample return mission [1]. As part of its instrument payload, Perseverance will carry the SuperCam instrument [2-3]. SuperCam combines a number of analytical techniques, notably a laser-induced breakdown spectroscopy (LIBS) instrument for chemical analysis that is coupled with a microphone for acoustic studies. The SuperCam microphone is a commercial of-the-shelf electret (based on Knowles EK-23132) and is designed to record sounds in the audible range, from 100 Hz to 10 kHz, during the surface mission. There are three main science investigations of interest for the SuperCam microphone: 1) Analysis of the LIBS acoustic signal; 2) study of atmospheric phenomena; and 3) examination of rover mechanical sounds. Since the atmosphere will be the source of acoustic signals, the microphone may be used to better understand the nature of the atmosphere and related phenomena such as thermal gradient and convective behavior in the rover"s vicinity [4], the behavior of dust devils [5], and to refine current atmospheric attenuation models for Mars [6]. Under atmosphere, LIBS analysis produces an acoustic signal due to the creation of a shock wave during laser ablation of a target. This acoustic signal can provide critical information about a target"s hardness and ablation depth [7-8] and whether there are coatings or thin layers present [9]. Mechanisms on the rover itself will also provide a source of acoustic signal that may be examined by the SuperCam microphone, notably sounds produced by the Mars Oxygen ISRU Experiment (MOXIE, [10]) instrument pumps during oxygen production. By the time of the conference, the SuperCam microphone should have acquired the first sounds on Mars; we will report on these exciting initial results and compare them to our prelanding expectations.[1] Farley K.A. et al. (2020) SSR 216, 142. [2] Wiens R.C. et al. (2021) SSR 217(4). [3] Maurice, S. et al. (in revision) SSR. [4] Chide, B. et al. (2020) 52nd LPSC. [5] Murdoch, N. et al. (2021) 52nd LPSC. [6] Chide, B. et al. (2020) AGU Fall meeting, S007-02. [7] Chide, B. et al. (2019) SAB 153, 50-60. [8] Chide, B. et al. (2020) SAB 174, 106000. [9] Lanza, N.L. et al (2020) 51st LPSC, no. 2807. [10] Hecht, M. H. et al. (2015) 46th LPSC, no. 2774

Combined LIBS and Acoustics for Differentiating Minerals with Similar LIBS Spectra

International audienceThe use of the plasma related spectroscopic and acoustic signals combined provide an innovative approach to characterize minerals with similar composition. This approach can help in the interpretation of the future data collected by M2020 mission

Combined LIBS and Acoustics for Differentiating Minerals with Similar LIBS Spectra

International audienceThe use of the plasma related spectroscopic and acoustic signals combined provide an innovative approach to characterize minerals with similar composition. This approach can help in the interpretation of the future data collected by M2020 mission

Combined LIBS and Acoustics for Differentiating Minerals with Similar LIBS Spectra

International audienceThe use of the plasma related spectroscopic and acoustic signals combined provide an innovative approach to characterize minerals with similar composition. This approach can help in the interpretation of the future data collected by M2020 mission