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  • 1.
    Wang, Jianfeng
    et al.
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Fonseca, Ricardo
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Rutledge, Kendall
    Novia University of Applied Sciences, Vaasa, Finland.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra, Granada, Spain The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University at Misasa, Tottori, Japan.
    Yu, Jun
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    A Hybrid Statistical-Dynamical Downscaling of Air Temperature over Scandinavia Using the WRF Model2020In: Advances in Atmospheric Sciences, ISSN 0256-1530, E-ISSN 1861-9533, Vol. 37, no 1, p. 57-74Article in journal (Refereed)
    Abstract [en]

    An accurate simulation of air temperature at local scales is crucial for the vast majority of weather and climate applications. In this work, a hybrid statistical–dynamical downscaling method and a high-resolution dynamical-only downscaling method are applied to daily mean, minimum and maximum air temperatures to investigate the quality of localscale estimates produced by downscaling. These two downscaling approaches are evaluated using station observation data obtained from the Finnish Meteorological Institute over a near-coastal region of western Finland. The dynamical downscaling is performed with the Weather Research and Forecasting (WRF) model, and the statistical downscaling method implemented is the Cumulative Distribution Function-transform (CDF-t). The CDF-t is trained using 20 years of WRF-downscaled Climate Forecast System Reanalysis data over the region at a 3-km spatial resolution for the central month of each season. The performance of the two methods is assessed qualitatively, by inspection of quantile-quantile plots, and quantitatively, through the Cramer-von Mises, mean absolute error, and root-mean-square error diagnostics. The hybrid approach is found to provide significantly more skillful forecasts of the observed daily mean and maximum air temperatures than those of the dynamical-only downscaling (for all seasons). The hybrid method proves to be less computationally expensive, and also to give more skillful temperature forecasts (at least for the Finnish near-coastal region).

  • 2.
    Escamilla-Roa, Elizabeth
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    Hernäandez-Laguna, Alfonso
    Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    Sainz-Diaz, Claro
    Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    DFT study of electronic and redox properties of TiO2 supported on olivine for modelling regolith on Moon and Mars conditions2020In: Planetary and Space Science, ISSN 0032-0633, E-ISSN 1873-5088, Vol. 180, article id 104760Article in journal (Refereed)
    Abstract [en]

    Titanium dioxide TiO2 is one of the most studied oxides in photocatalysis, due to its electronic structure and its wide variety of applications, such as gas sensors and biomaterials, and especially in methane-reforming catalysis. Titanium dioxide and olivine have been detected both on Mars and our Moon. It has been postulated that on Mars photocatalytic processes may be relevant for atmospheric methane fluctuation, radicals and perchlorate productions etc. However, to date no investigation has been devoted to modelling the properties of TiO2 adsorbed on olivine surface.

    The goal of this study is to investigate at atomic level with electronic structure calculations based on the Density Functional Theory (DFT), the atomic interactions that take place during the adsorption processes for formation of a TiO regolith. This model is formed with different TiO films adsorbed on olivine (forsterite) surfaces, one of the most common minerals in Universe, Earth, Mars, cometary and interstellar dust. We propose three regolith models to simulate the principal phase of titanium oxide (TiO, Ti2O3 and TiO2). The models show different adsorption processes i.e. physisorption and chemisorption. Our results suggest that the TiO is the most reactive phase and produces a strong exothermic effect. Besides, we have detailed, from a theoretical point of view, the effect that has the adsorption process in the electronic properties such as electronic density of state (DOS) and oxide reduction process (redox). This theoretical study can be important to understand the formation of new materials (supports) that can be used as support in the catalytic processes that occur in the Earth, Mars and Moon. Also, it may be important to interpret the present day photochemistry and interaction of regolith and airborne aerosols in the atmosphere on Mars or to define possible catalytic reactions of the volatiles captured on the Moon regolith.

  • 3.
    Escamilla-Roa, Elizabeth
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    Hernández-Laguna, Alfonso
    Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    Saínz-Díaz, C.Ignacio
    Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    DFT study of the reduction reaction of calcium perchlorate on olivine surface: Implications to formation of Martian’s regolith2020In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 512, article id 145634Article in journal (Refereed)
    Abstract [en]

    Perchlorates have been found widespread on the surface of Mars, their origin and degradation pathways are not understood to date yet. We investigate here, from a theoretical point of view, the potential redox processes that take place in the interaction of Martian minerals such as olivine, with anhydrous and hydrated perchlorates. For this theoretical study, we take as mineral substrate the (1 0 0) surface of forsterite and calcium perchlorate salt as adsorbate. Our DFT calculations suggests a reduction pathway to chlorate and chlorite. When the perchlorate has more than 4 water molecules, this mechanism, which does not require high-temperature or high energy sources, results in parallel with the oxidation of the mineral surface, forming magnesium peroxide, MgO2, and in the formation of ClO3, which through photolysis is known to form ClO-O2. Because of the high UV irradiance that reaches the surface of Mars, this may be a source of O2 on Mars. Our results suggest that this process may be a natural removal pathway for perchlorates from the Martian regolith, which in the presence of atmospheric water for salt hydration, can furthermore lead to the production of oxygen. This mechanism may thus have implications on the present and future habitability of the Martian surface.

  • 4.
    Soria-Salinas, Álvaro
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Torrejó n de Ardoz, 28850 Madrid, Spain.
    Mantas-Nakhai, Roberto
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martín-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), 18100 Granada, Spain.
    Wind retrieval from temperature measurements from the Rover Environmental Monitoring Station/Mars Science Laboratory2020In: Icarus (New York, N.Y. 1962), ISSN 0019-1035, E-ISSN 1090-2643, article id 113785Article in journal (Refereed)
    Abstract [en]

    This work presents a novel method for the real-time retrieval of wind speed on the surface of Mars that uses temperature measurements from the Rover Environmental Monitoring Station (REMS) instrument onboard the Curiosity rover of the Mars Science Laboratory (MSL) mission. After final failure of the Wind Sensor (WS) in sol 1491, REMS has not been providing wind data. The new wind retrieval approach that we propose may eventually be able to supply MSL with wind values for contextualizing the roverâôs operations and for meteorological studies on the surface of Mars. The new method is based on forced convection modeling of the Air Temperature Sensors (ATS) of REMS as thin rods immersed in the extreme low-pressure and high-radiating atmospheric conditions of the Martian thermal boundary layer at a height of ∼" role="presentation" style="box-sizing: border-box; margin: 0px; padding: 0px; display: inline-block; line-height: normal; font-size: 16.2px; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; position: relative;">∼ 1.5 m from the surface. A preliminary validation of the possibilities and limitations of this retrieval has been performed using comparative analysis with existing REMS wind field-site data for the same sols that are available at the Planetary Data System (PDS). We have developed both a ”coarse” approach, in which wind speed is determined with no regard to wind direction, and a ”refined” method, in which it is attempted to determine both wind speed and direction. Assuming the previously reported WS retrieval errors of 20% for the wind speed, we report an agreement to the WS values of wind speed ranging from 36.4% to 77% of the acquisition time for the ”coarse” approach, depending on the sol examined. These promising results are limited to only evening extended acquisitions from 18:00 to 21:00 local mean solar time (LMST). This method could be applied to daytime conditions. The results suggest a new optimal orientation for wind speed retrieval of 60°clockwise with respect to the forward direction of the Curiosity rover, although the technique is not yet ready to be considered for planning of the Curiosity rover operations. This method could extend the wind characterization of the Gale Crater for future Curiosity rover data acquisitions by recycling air temperature measurements and provide the scientific community with a data set for future comparative analysis with the Temperature and Wind Sensors for InSight (TWINS)/InSight, the HabitAbility: Brines, Irradiation and Temperature (HABIT)/ExoMars 2020, and the Mars Environmental Dynamics Analyzer (MEDA)/Mars 2020 rover instruments.

  • 5.
    Fonseca, Ricardo
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Madrid, Spain.
    Azu-Bustos, Armando
    Centro de Astrobiología (INTA-CSIC), Madrid, Spain. Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile.
    González-Silva, Carlos
    Facultad de Ciencias, Universidad de Tarapacá, Iquique, Chile.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (UGR-CSIC), Granada, Spain.
    A surface temperature and moisture intercomparison study of the Weather Research and Forecasting model, in‐situ measurements and satellite observations over the Atacama Desert2019In: Quarterly Journal of the Royal Meteorological Society, ISSN 0035-9009, E-ISSN 1477-870X, Vol. 145, no 722, p. 2202-2220Article in journal (Refereed)
    Abstract [en]

    Good knowledge of the environmental conditions of deserts on Earth is relevant forclimate studies. The Atacama Desert is of particular interest as it is considered tobe the driest region on Earth. We have performed simulations using the WeatherResearch and Forecasting (WRF) model over the Atacama Desert for two week-longperiods in the austral winter season coincident with surface temperature and relativehumidity in-situ observations at three sites. We found that the WRF model generallyoverestimates the daytime surface temperature, with biases of up to 11◦C, despitegiving a good simulation of the relative humidity. In order to improve the agree-ment with observed measurements, we conducted sensitivity experiments in whichthe surface albedo, soil moisture content and five tuneable parameters in the NoahLand Surface Model (namely soil porosity, soil suction, saturated soil hydraulic con-ductivity, thebparameter used in hydraulic functions and the quartz fraction) areperturbed. We concluded that an accurate simulation is not possible, most likelybecause the Noah Land Surface Model does not have a groundwater table that maybe shallow in desert regions. The WRF-predicted land surface temperature is alsoevaluated against that estimated from the Moderate Resolution Imaging Spectrora-diometer (MODIS) instrument. While at night the satellite-derived and ground-basedmeasurements are generally in agreement, during the day MODIS estimates aretypically lower by as much as 17◦C. This is attributed to the large uncertainty inthe MODIS-estimated land surface temperatures in arid and semi-arid regions. Thefindings of this work highlight the need for ground-based observational networksin remote regions such as the Atacama Desert where satellite-derived and modelproducts may not be very accurate.

  • 6.
    Navarro‐González, Rafael
    et al.
    Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Mexico City, Mexico.
    Navarro, Karina F.
    Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Mexico City, Mexico.
    Coll, Patrice
    Laboratoire Interuniversitaire des Systèmes Atmosphériques, CNRS UMR 7583, Université Paris‐Est Créteil, Université Paris Diderot, Créteil, France.
    McKay, Christopher P.
    NASA Ames Research Center, Moffett Field, CA, USA.
    Stern, Jennifer C.
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Sutter, Brad
    Jacobs, NASA Johnson Space Center, Houston, TX, USA.
    Archer Jr, P. Douglas
    Jacobs, NASA Johnson Space Center, Houston, TX, USA.
    Buch, Arnaud
    Ecole Centrale Paris, Châtenay‐Malabry, France.
    Cabane, Michel
    Laboratoire Atmosphère, Milieux, Observations Spatiales, UMR CNRS 8190, Université Versailles Saint‐Quentin en Yvelines, UPMC Université Paris 06, Guyancourt, France.
    Conrad, Pamela G
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Eigenbrode, Jennifer L.
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Franz, Heather B.
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Freissinet, Caroline
    Laboratoire Atmosphère, Milieux, Observations Spatiales, UMR CNRS 8190, Université Versailles Saint‐Quentin en Yvelines, UPMC Université Paris 06, Guyancourt, France.
    Glavin, Daniel P.
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Hogancamp, Joanna V.
    Jacobs, NASA Johnson Space Center, Houston, TX, USA.
    McAdam, Amy C.
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Malespin, Charles A.
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    Ming, Douglas W.
    NASA Johnson Space Center, Houston, TX, USA.
    Morris, Richard V.
    NASA Johnson Space Center, Houston, TX, USA.
    Prats, Benny
    NASA/eINFORMe, Inc., Goddard Space Flight Center, Planetary Environments Laboratory, Greenbelt, MD, USA.
    Raulin, François
    Laboratoire Interuniversitaire des Systèmes Atmosphériques, CNRS UMR 7583, Université Paris‐Est Créteil, Université Paris Diderot, Créteil, France.
    Rodríguez‐Manfredi, José Antonio
    Centro de Astrobiología (INTA-CSIC), Madrid, Spain.
    Szopa, Cyril
    Laboratoire Atmosphère, Milieux, Observations Spatiales, UMR CNRS 8190, Université Versailles Saint‐Quentin en Yvelines, UPMC Université Paris 06, Guyancourt, France.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Madrid, Spain.
    Mahaffy, Paul R.
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Atreya, Sushil
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Trainer, Melissa G.
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Vasavada, Ashwin R.
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Abiotic Input of Fixed Nitrogen by Bolide Impacts to Gale Crater During the Hesperian: Insights From the Mars Science Laboratory2019In: Journal of Geophysical Research - Planets, ISSN 2169-9097, E-ISSN 2169-9100, Vol. 124, no 1, p. 94-113Article in journal (Refereed)
    Abstract [en]

    Molecular hydrogen (H2) from volcanic emissions is suggested to warm the Martian surface when carbon dioxide (CO2) levels dropped from the Noachian (4100 to 3700 Myr) to the Hesperian (3700 to 3000 Myr). Its presence is expected to shift the conversion of molecular nitrogen (N2) into different forms of fixed nitrogen (N). Here we present experimental data and theoretical calculations that investigate the efficiency of nitrogen fixation by bolide impacts in CO2‐N2 atmospheres with or without H2. Surprisingly, nitric oxide (NO) was produced more efficiently in 20% H2 in spite of being a reducing agent and not likely to increase the rate of nitrogen oxidation. Nevertheless, its presence led to a faster cooling of the shock wave raising the freeze‐out temperature of NO resulting in an enhanced yield. We estimate that the nitrogen fixation rate by bolide impacts varied from 7 × 10−4 to 2 × 10−3 g N·Myr−1·cm−2 and could imply fluvial concentration to explain the nitrogen (1.4 ± 0.7 g N·Myr−1·cm−2) detected as nitrite (NO2−) and nitrate (NO3−) by Curiosity at Yellowknife Bay. One possible explanation is that the nitrogen detected in the lacustrine sediments at Gale was deposited entirely on the crater's surface and was subsequently dissolved and transported by superficial and ground waters to the lake during favorable wet climatic conditions. The nitrogen content sharply decreases in younger sediments of the Murray formation suggesting a decline of H2 in the atmosphere and the rise of oxidizing conditions causing a shortage in the supply to putative microbial life.

  • 7.
    Azua-Bustos, Armando
    et al.
    Centro de Astrobiología (CSIC-INTA), Madrid, Spain. Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile.
    González-Silva, Carlos
    Facultad de Ciencias, Universidad de Tarapacá, Arica, Chile.
    Fernández-Martínez, Miguel Ángel
    Centro de Astrobiología (CSIC-INTA), Madrid, Spain.
    Arenas-Fajardo, Cristián
    Atacama Biotech, Santiago, Chile.
    Fonseca, Ricardo
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (UGR-CSIC), Armilla, Granada, Spain.
    Fernández-Sampedro, Maite
    Centro de Astrobiología (CSIC-INTA), Madrid, Spain.
    Fairén, Alberto G.
    Centro de Astrobiología (CSIC-INTA), Madrid, Spain. Department of Astronomy, Cornell University, Ithaca, NY, USA.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Aeolian transport of viable microbial life across the Atacama Desert, Chile: Implications for Mars2019In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, article id 11024Article in journal (Refereed)
    Abstract [en]

    Here we inspect whether microbial life may disperse using dust transported by wind in the Atacama Desert in northern Chile, a well-known Mars analog model. By setting a simple experiment across the hyperarid core of the Atacama we found that a number of viable bacteria and fungi are in fact able to traverse the driest and most UV irradiated desert on Earth unscathed using wind-transported dust, particularly in the later afternoon hours. This finding suggests that microbial life on Mars, extant or past, may have similarly benefited from aeolian transport to move across the planet and find suitable habitats to thrive and evolve.

  • 8.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Institut für Kartographie, Technische Universität Dresden, Dresden, Germany. Department of Environmental Science, Sharda University, Greater Noida, India.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC ‐ UGR), Armilla, Spain. UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Madrid, Spain.
    Are Slope Streaks Indicative of Global‐Scale Aqueous Processes on Contemporary Mars?2019In: Reviews of geophysics, ISSN 8755-1209, E-ISSN 1944-9208, Vol. 57, no 1, p. 48-77Article in journal (Refereed)
    Abstract [en]

    Slope streaks are prevalent and intriguing dark albedo surface features on contemporary Mars. Slope streaks are readily observed in the equatorial and subequatorial dusty regolith regions with low thermal inertia. They gradually fade over decadal timescales. The proposed mechanisms for their formation vary widely based on several physicochemical and geomorphological explanations. The scientific community is divided in proposing both dry and wet mechanisms for the formation of slope streaks. Here we perform a systematic evaluation of the literature for these wet and dry mechanisms. We discuss the probable constraints on the various proposed mechanisms and provide perspectives on the plausible process driving global‐scale slope streak formation on contemporary Mars. Although per our understanding, a thorough consideration of the global distribution of slope streaks, their morphology and topography, flow characteristics, physicochemical and atmospheric coincidences, and terrestrial analogies weighs more in favor of several wet mechanisms, we acknowledge that such wet mechanisms cannot explain all the reported morphological and terrain variations of slope streaks. Thus, we suggest that explanations considering both dry and wet processes can more holistically describe all the observed morphological variations among slope streaks. We further acknowledge the constraints on the resolutions of remote sensing data and on our understanding of the Martian mineralogy, climate, and atmosphere and recommend continuous investigations in this direction using future remote sensing acquisitions and simulations. In this regard, finding more wet and dry terrestrial analogs for Martian slope streaks and studying them at high spatiotemporal resolutions can greatly improve our understanding.

  • 9.
    Israel Nazarious, Miracle
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Vakkada Ramachandran, Abhilash
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Torrejon de Ardoz, Madrid, Spain.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Calibration and preliminary tests of the Brine Observation Transition To Liquid Experiment on HABIT/ExoMars 2020 for demonstration of liquid water stability on Mars2019In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 162, p. 497-510Article in journal (Refereed)
    Abstract [en]

    The search for unequivocal proofs of liquid water on present day Mars is a prominent domain of research with implications on habitability and future Mars exploration. The HABIT (Habitability: Brines, Irradiation, and Temperature) instrument that will be on-board the ExoMars 2020 Surface Platform (ESA-IKI Roscosmos) will investigate the habitability of present day Mars, monitoring temperature, winds, dust conductivity, ultraviolet radiation and liquid water formation. One of the components of HABIT is the experiment BOTTLE (Brine Observation Transition To Liquid Experiment). The purposes of BOTTLE are to: (1) quantify the formation of transient liquid brines; (2) observe their stability over time under non-equilibrium conditions; and (3) serve as an In-Situ Resource Utilization (ISRU) technology demonstrator for water moisture capture. In this manuscript, we describe the calibration procedure of BOTTLE with standard concentrations of brines, the calibration function and the coefficients needed to interpret the observations on Mars.

    BOTTLE consists of six containers: four of them are filled with different deliquescent salts that have been found on Mars (calcium-perchlorate, magnesium-perchlorate, calcium-chloride, and sodium-perchlorate); and two containers that are open to the air, to collect atmospheric dust. The salts are exposed to the Martian environment through a high efficiency particulate air (HEPA) filter (to comply with planetary protection protocols). The deliquescence process will be monitored by observing the changes in electrical conductivity (EC) in each container: dehydrated salts show low EC, hydrated salts show medium EC and, liquid brines show high EC values. We report and interpret the preliminary test results using the BOTTLE engineering model in representative conditions; and we discuss how this concept can be adapted to other exploration missions.

    Our laboratory observations show that 1.2 g of anhydrous calcium-chloride captures about 3.7 g of liquid water as brine passing through various possible hydrate forms. This ISRU technology could potentially be the first attempt to understand the formation of transient liquid water on Mars and to develop self-sustaining in-situ water harvesting on Mars for future human and robotic missions.

  • 10.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Discovery of recurring slope lineae candidates in Mawrth Vallis, Mars2019In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, article id 2040Article in journal (Refereed)
    Abstract [en]

    utside of established RSL regions and further prompt the inclusion of a new geographical region within the RSL candidate group. Our inferences on the RSL candidates are based on several morphological and geophysical evidences and analogies: (i) the dimensions of the RSL candidates are consistent with confirmed mid-latitude RSL; (ii) albedo and thermal inertia values are comparable to those of other mid-latitude RSL sites; and (iii) features are found in a summer season image and on the steep and warmest slopes. These results denote the plausible presence of transient liquid brines close to the previously proposed landing ellipse of the ExoMars rover, rendering this site particularly relevant to the search of life. Further investigations of Mawrth Vallis carried out at higher spatial and temporal resolutions are needed to identify more of such features at local scales to maximize the scientific return from the future Mars rovers, to prevent probable biological contamination during rover operations, to evade damage to rover components as brines can be highly corrosive, and to quantify the ability of the regolith at mid-latitudes to capture atmospheric water which is relevant for in-situ-resource utilization.

  • 11.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Armilla, Granada, Spain.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain.
    Distribution and Morphologies of Transverse Aeolian Ridges in ExoMars 2020 Rover Landing Site2019In: Remote Sensing, ISSN 2072-4292, E-ISSN 2072-4292, Vol. 11, no 8, article id 912Article in journal (Refereed)
    Abstract [en]

    Aeolian processes are believed to play a major role in the landscape evolution of Mars. Investigations on Martian aeolian landforms such as ripples, transverse aeolian ridges (TARs), and dunes, and aeolian sediment flux measurements are important to enhance our understanding of past and present wind regimes, the ongoing dust cycle, landscape evolution, and geochemistry. These aeolian bedforms are often comprised of loose sand and sharply undulating topography and thus pose a threat to mobility and maneuvers of Mars rovers. Here we present a first-hand account of the distribution, morphologies, and morphometrics of TARs in Oxia Planum, the recently selected ExoMars 2020 Rover landing site. The gridded mapping was performed for contiguous stretches of TARs within all the landing ellipses using 57 sub-meter high resolution imaging science experiment (HiRISE) scenes. We also provide the morphological descriptions for all types of TARs present within the landing ellipses. We use HiRISE digital terrain models (DTMs) along with the images to derive morphometric information for TARs in Oxia Planum. In general, the average areal TAR coverage was found to be 5.4% (±4.9% standard deviation), increasing from west to east within the landing ellipses. We report the average TAR morphometrics in the form of crest–ridge width (131.1 ± 106.2 m), down-wind TAR length (17.6 ± 10.1 m), wavelength (37.3 ± 11.6 m), plan view aspect ratio (7.1 ± 2.3), inter-bedform spacing (2.1 ± 1.1), slope (10.6° ± 6.1°), predominant orientations (NE-SW and E-W), and height (1.2 ± 0.8 m). While simple TARs are predominant, we report other TAR morphologies such as forked TAR, wavy TAR with associated smaller secondary ripples, barchan-like TAR, networked TAR, and mini-TARs from the region. Our results can help in planning the rover traverses in terms of both safe passage and scientific returns favoring aeolian research, particularly improving our understanding of TARs.

  • 12.
    Fonseca, Ricardo
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martín-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), 18100 Granada, Spain.
    High-Resolution Dynamical Downscaling of Re-Analysis Data over the Kerguelen Islands using the WRF Model2019In: Journal of Theoretical and Applied Climatology, ISSN 0177-798X, E-ISSN 1434-4483, Vol. 135, no 3-4, p. 1259-1277Article in journal (Refereed)
    Abstract [en]

    We have used the Weather Research and Forecasting (WRF) model to simulate the climate of the Kerguelen Islands (49° S, 69° E) and investigate its inter-annual variability. Here, we have dynamically downscaled 30 years of the Climate Forecast System Reanalysis (CFSR) over these islands at 3-km horizontal resolution. The model output is found to agree well with the station and radiosonde data at the Port-aux-Français station, the only location in the islands for which observational data is available. An analysis of the seasonal mean WRF data showed a general increase in precipitation and decrease in temperature with elevation. The largest seasonal rainfall amounts occur at the highest elevations of the Cook Ice Cap in winter where the summer mean temperature is around 0 °C. Five modes of variability are considered: conventional and Modoki El Niño-Southern Oscillation (ENSO), Indian Ocean Dipole (IOD), Subtropical IOD (SIOD) and Southern Annular Mode (SAM). It is concluded that a key mechanism by which these modes impact the local climate is through interaction with the diurnal cycle in particular in the summer season when it has a larger magnitude. One of the most affected regions is the area just to the east of the Cook Ice Cap extending into the lower elevations between the Gallieni and Courbet Peninsulas. The WRF simulation shows that despite the small annual variability, the atmospheric flow in the Kerguelen Islands is rather complex which may also be the case for the other islands located in the Southern Hemisphere at similar latitudes.

  • 13.
    Pandey, S.
    et al.
    Mars Society Australia, Clifton Hill, VIC, Australia. Amity Centre of Excellence in Astrobiology, Amity University Mumbai, Mumbai, India. Blue Marble Space Institute of Science, Seattle, WA, United States.
    Clarke, J.
    Mars Society Australia, Clifton Hill, VIC, Australia.Australian Centre of Astrobiology, University of New South Wales, Sydney, NSW, Australia.
    Nema, P.
    Blue Marble Space Institute of Science, Seattle, WA, United States.
    Bonaccorsi, R.
    Space Sciences Division, NASA Ames Research Center, Moffett Field, CA, United States. SETI Institute, Carl Sagan Center, Mountain View, CA, United States.
    Som, S.
    Blue Marble Space Institute of Science, Seattle, WA, United States.
    Sharma, M.
    Birbal Sahni Institute of Palaeosciences, Lucknow, India.
    Phartiyal, B.
    Birbal Sahni Institute of Palaeosciences, Lucknow, India.
    Rajamani, S.
    Indian Institute of Science Education and Research, Pune, India.
    Mogul, R.
    Blue Marble Space Institute of Science, Seattle, WA, United States. California Polytechnic University, Pomona, CA, United States.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Armilla, Granada, Spain.
    Vaishampayan, P.
    Blue Marble Space Institute of Science, Seattle, WA, United States.
    Blank, J.
    Blue Marble Space Institute of Science, Seattle, WA, United States.Space Sciences Division, NASA Ames Research Center, Moffett Field, CA, United States.
    Steller, L.
    Australian Centre of Astrobiology, University of New South Wales, Sydney, NSW, Australia.
    Srivastava, A
    Mars Society, Lakewood, CO, United States.
    Singh, R.
    Birbal Sahni Institute of Palaeosciences, Lucknow, India.
    McGuirk, S.
    Mars Society Australia, Clifton Hill, VIC, Australia. Fenner School of Environment and Society, Australian National University, Australian Capital Territory, Australia.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain.
    Güttler, J.M.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Cal, Maria Teresa Mendaza de
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Soria-Salinas, Álvaro
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Ahmad, S.
    Birbal Sahni Institute of Palaeosciences, Lucknow, India.
    Ansari, A.
    Birbal Sahni Institute of Palaeosciences, Lucknow, India.
    Singh, V.K
    Birbal Sahni Institute of Palaeosciences, Lucknow, India.
    Mungi, C.
    Indian Institute of Science Education and Research, Pune, India.
    Bapat, N.
    Indian Institute of Science Education and Research, Pune, India.
    Ladakh: Diverse, high-altitude extreme environments for off-earth analogue and astrobiology research2019In: International Journal of Astrobiology, ISSN 1473-5504, E-ISSN 1475-3006Article in journal (Refereed)
    Abstract [en]

    This paper highlights unique sites in Ladakh, India, investigated during our 2016 multidisciplinary pathfinding expedition to the region. We summarize our scientific findings and the site's potential to support science exploration, testing of new technologies and science protocols within the framework of astrobiology research. Ladakh has several accessible, diverse, pristine and extreme environments at very high altitudes (3000–5700 m above sea level). These sites include glacial passes, sand dunes, hot springs and saline lake shorelines with periglacial features. We report geological observations and environmental characteristics (of astrobiological significance) along with the development of regolith-landform maps for cold high passes. The effects of the diurnal water cycle on salt deliquescence were studied using the ExoMars Mission instrument mockup: HabitAbility: Brines, Irradiance and Temperature (HABIT). It recorded the existence of an interaction between the diurnal water cycle in the atmosphere and salts in the soil (which can serve as habitable liquid water reservoirs). Life detection assays were also tested to establish the best protocols for biomass measurements in brines, periglacial ice-mud and permafrost melt water environments in the Tso-Kar region. This campaign helped confirm the relevance of clays and brines as interest targets of research on Mars for biomarker preservation and life detection.

  • 14.
    Guzewich, Scott D.
    et al.
    NASA Goddard Spaceflight Center,Greenbelt, MD, USA.
    Lemmon, M.
    Space Science Institute, College Station, TX, USA.
    Smith, C.L
    Department of Earth and Space Science and Engineering, York University, Toronto, Ontario, Canada.
    Martínez, G.
    College of Engineering, University of Michigan, Ann Arbor, MI, USA.
    de Vicente‐Retortillo, Á.
    College of Engineering, University of Michigan, Ann Arbor, MI, USA.
    Newman, C. E.
    Aeolis Research, Pasadena, CA, USA.
    Baker, M.
    Department of Earth and Planetary Science, The Johns Hopkins University, Baltimore, MD, USA.
    Campbell, C.
    Department of Earth and Space Science and Engineering, York University, Toronto, Ontario, Canada.
    Cooper, B.
    Department of Earth and Space Science and Engineering, York University, Toronto, Ontario, Canada.
    Gómez‐Elvira, J.
    Centro de Astrobiología (INTA-CSIC), Madrid, Spain.
    Harri, A.‐M.
    Finnish Meteorological Institute, Helsinki, Finland.
    Hassler, D.
    Southwest Research Institute, Boulder, CO, USA.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC‐UGR), Armilla, Granada, Spain.
    McConnochie, T.
    Department of Astronomy, University of Maryland, College Park, MD, USA.
    Moores, J. E.
    Department of Earth and Space Science and Engineering, York University, Toronto, Ontario, Canada.
    Kahanpää, H.
    Finnish Meteorological Institute, , Helsinki, Finland; School of Electrical Engineering, Aalto University, , Espoo, Finland.
    Khayat, A.
    NASA Goddard Spaceflight Center, Greenbelt, MD, USA;CRESST II and Department of Astronomy, University of Maryland, College Park, MD, USA.
    Richardson, M. I.
    Aeolis Research, Pasadena, CA, USA.
    Smith, M.D
    NASA Goddard Spaceflight Center, Greenbelt, MD, USA.
    Sullivan, R.
    Cornell Center for Astrophysics and Planetary Science, Cornell University, Ithaca, NY, USA.
    de la Torre Juarez, M.
    Cornell Center for Astrophysics and Planetary Science, Cornell University, Ithaca, NY, USA.
    Vasavada, A.R
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA.
    Viúdez‐Moreiras, D.
    Centro de Astrobiología (INTA-CSIC), Madrid, Spain.
    Zeitlin, C.
    Leidos, Houston, TX, USA.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Mars Science Laboratory Observations of the 2018/Mars Year 34 Global Dust Storm2019In: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 46, no 1, p. 71-79Article in journal (Refereed)
    Abstract [en]

    Mars Science Laboratory Curiosity rover observations of the 2018/Mars year 34 global/planet‐encircling dust storm represent the first in situ measurements of a global dust storm with dedicated meteorological sensors since the Viking Landers. The Mars Science Laboratory team planned and executed a science campaign lasting approximately 100 Martian sols to study the storm involving an enhanced cadence of environmental monitoring using the rover's meteorological sensors, cameras, and spectrometers. Mast Camera 880‐nm optical depth reached 8.5, and Rover Environmental Monitoring Station measurements indicated a 97% reduction in incident total ultraviolet solar radiation at the surface, 30K reduction in diurnal range of air temperature, and an increase in the semidiurnal pressure tide amplitude to 40 Pa. No active dust‐lifting sites were detected within Gale Crater, and global and local atmospheric dynamics were drastically altered during the storm. This work presents an overview of the mission's storm observations and initial results.

  • 15.
    Fonseca, Ricardo Morais
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    MARSWRF Prediction of Entry Descent Landing Profiles: Applications to Mars Exploration2019In: Earth and Space Science, E-ISSN 2333-5084, Vol. 6, no 8, p. 1440-1459Article in journal (Refereed)
    Abstract [en]

    In this paper we use the Mars implementation of the Planet Weather Research and Forecasting model, MarsWRF, to simulate the Entry, Descent and Landing (EDL) vertical profiles from six past missions: Pathfinder, Mars Exploration Rovers Opportunity and SpiritPhoenix, Mars Science Laboratory Curiosity rover and ExoMars 2016 (Schiaparelli), and compare the results with observed data. In order to investigate the sensitivity of the model predictions to the atmospheric dust distribution, MarsWRF is run with two prescribed dust scenarios. It is concluded that the MarsWRF EDL predictions can be used for guidance into the design and planning stage of future missions to the planet, as it generally captures the observed EDL profiles, although it has a tendency to underestimate the temperature and overestimate the density for heights above 15 km. This could be attributed to an incorrect representation of the observed dust loading. We have used the model to predict the EDL conditions that may be encountered by two future missions: ExoMars 2020 and Mars 2020. When run for Oxia Planum and Jezero Crater for the expected landing time, MarsWRF predicts a large sensitivity to the dust loading in particular for the horizontal wind speed above 10‐15 km with maximum differences of up to ±30 m s‐1 for the former and ±15 m s‐1 for the latter site. For both sites, the best time for EDL, i.e. when the wind speed is generally the weakest with smaller shifts in direction, is predicted to be in the late morning and early afternoon.

  • 16.
    Vandaele, Ann Carine
    et al.
    Royal Belgian Institute for Space Aeronomy (IASB-BIRA), Brussels, Belgium.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Univ Granada, Inst Andaluz Ciencias Tierra, Granada, Spain.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Inst Nacl Tecn Aeroespacial CSIC INTA, Ctr Astrobiol, Madrid, Spain.
    Martian dust storm impact on atmospheric H2O and D/H observed by ExoMars Trace Gas Orbiter2019In: Nature, ISSN 1476-4687, Vol. 568, no 7753, p. 521-525Article in journal (Refereed)
    Abstract [en]

    Global dust storms on Mars are rare1,2 but can affect the Martian atmosphere for several months. They can cause changes in atmospheric dynamics and inflation of the atmosphere3, primarily owing to solar heating of the dust3. In turn, changes in atmospheric dynamics can affect the distribution of atmospheric water vapour, with potential implications for the atmospheric photochemistry and climate on Mars4. 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 latitudes5,6, as well as a decrease in the water column at low latitudes7,8. 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/H2O 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 crystals3. 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.

  • 17.
    Durán, Pablo
    et al.
    Norwegian University of Life Sciences, Ås, Norway.WindSim AS, Tønsberg, Norway.
    Meißner, Cathérine
    WindSim AS, Tønsberg, Norway.
    Rutledge, Kendall
    Novia University of Applied Sciences, Vasa, Finland.
    Fonseca, Ricardo
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    Adaramola, Muyiwa S.
    Norwegian University of Life Sciences, Ås, Norway.
    Meso-microscale coupling for wind resource assessment using averaged atmospheric stability conditions2019In: Meteorologische Zeitschrift, ISSN 0941-2948, E-ISSN 1610-1227, Vol. 28, no 4, p. 273-291Article in journal (Refereed)
    Abstract [en]

    A methodology to couple Numerical Weather Prediction (NWP) models with steady-state Computational Fluid Dynamic (CFD) models for wind resource assessment applications is proposed. NWP simulations are averaged according to their atmospheric stability and wind direction. The averaged NWP simulations are used to generate the initial and boundary conditions of the CFD model. The method is applied using one year of Weather Research and Forecasting (WRF) simulations at the Honkajoki wind farm in Finland and validated by Sonic Detection and Ranging (SODAR) measurements at the site. It is shown that coupled simulations reproduce a more realistic shear for heights above 150 m. In terms of estimated energy production, there is not a big difference between coupled and standalone models. Nevertheless, a considerable difference in the horizontal wind speed patterns can be seen between the coupled and non-coupled approaches. The WRF model resolution has only a small influence on the coupled CFD results.

  • 18.
    Martorell, José Antonio Gordillo
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Israel Nazarious, Miracle
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Mathanlal, Thasshwin
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    Zorzano, María Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (CSIC-INTA), Madrid, Spain.
    Thurfjell, Magnus
    Porsöskolan, Lulea, Sweden.
    Antich Lunqvist, Margaretta
    Porsöskolan, Lulea, Sweden.
    Metabolizing science from the laboratory to the classroom: The Metabolt Educational Experience2019In: Journal of Engineering Science and Technology, Vol. 2, no 7, p. 9-26Article in journal (Refereed)
    Abstract [en]

    The present article summarizes a pilot knowledge co-creation process experience done with a group of 15 eleven and twelve years old students of Porsöskolan, a public school near Luleå Tekniska Universitet from September 2018 to January 2019. The experience is based on a true research project of the Group of Atmospheric Science (GAS) called METABOLT, an instrument to investigate the metabolic activity of microorganisms in soils by measuring the electrochemical and gaseous bio signatures. In this paper, we explain how we have designed, developed, applied and evaluated a complete learning and engagement strategy to bring science from the laboratory to the classroom. The experience adapts the scientific method to the primary classroom level, taking as practical case the METABOLT experiment: identification of a problem, hypothesis design, experiment creation to get results, analysis and confrontation with the hypothesis and provisional conclusions to verify or discard them. After the experience a set of surveys were given to all the stakeholders, students, teachers and researchers to evaluate their perception of the effects of the activity. One unexpected result is the difference in perception between the teachers and students on the learning experience. This project demonstrates that professional researchers with the adequate communication strategy, training and tracking can promote a relevant learning process and achieve a social impact in different audiences

  • 19. Korablev, Oleg
    et al.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Vago, Jorge L.
    European Space Research and Technology Centre (ESTEC), ESA, Noordwijk, The Netherlands.
    No detection of methane on Mars from early ExoMars Trace Gas Orbiter observations2019In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 568, p. 517-520Article in journal (Refereed)
    Abstract [en]

    The detection of methane on Mars has been interpreted as indicating that geochemical or biotic activities could persist on Mars today1. A number of different measurements of methane show evidence of transient, locally elevated methane concentrations and seasonal variations in background methane concentrations2,3,4,5. These measurements, however, are difficult to reconcile with our current understanding of the chemistry and physics of the Martian atmosphere6,7, which—given methane’s lifetime of several centuries—predicts an even, well mixed distribution of methane1,6,8. 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 detections2,4. We suggest that reconciliation between the present findings and the background methane concentrations found in the Gale crater4 would require an unknown process that can rapidly remove or sequester methane from the lower atmosphere before it spreads globally.

  • 20.
    Singh, Shaktiman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Bhardwaj, Anshuman
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Singh, Atar
    Department of Environmental Science, Sharda University, Greater Noida, India.
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Shekhar, Mayank
    Birbal Sahni Institute of Palaeosciences, Lucknow, India.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Armilla, Granada, Spain.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Madrid, Spain.
    Quantifying the Congruence between Air and Land Surface Temperatures for Various Climatic and Elevation Zones of Western Himalaya2019In: Remote Sensing, ISSN 2072-4292, E-ISSN 2072-4292, Vol. 11, no 24, article id 2889Article in journal (Refereed)
    Abstract [en]

    The surface and near-surface air temperature observations are primary data for glacio-hydro-climatological studies. The in situ air temperature (Ta) observations require intense logistic and financial investments, making it sparse and fragmented particularly in remote and extreme environments. The temperatures in Himalaya are controlled by a complex system driven by topography, seasons, and cryosphere which further makes it difficult to record or predict its spatial heterogeneity. In this regard, finding a way to fill the observational spatiotemporal gaps in data becomes more crucial. Here, we show the comparison of Ta recorded at 11 high altitude stations in Western Himalaya with their respective land surface temperatures (Ts) recorded by Moderate Resolution Imagining Spectroradiometer (MODIS) Aqua and Terra satellites in cloud-free conditions. We found remarkable seasonal and spatial trends in the Ta vs. Ts relationship: (i) Ts are strongly correlated with Ta (R2 = 0.77, root mean square difference (RMSD) = 5.9 °C, n = 11,101 at daily scale and R2 = 0.80, RMSD = 5.7 °C, n = 3552 at 8-day scale); (ii) in general, the RMSD is lower for the winter months in comparison to summer months for all the stations, (iii) the RMSD is directly proportional to the elevations; (iv) the RMSD is inversely proportional to the annual precipitation. Our results demonstrate the statistically strong and previously unreported Ta vs. Ts relationship and spatial and seasonal variations in its intensity at daily resolution for the Western Himalaya. We anticipate that our results will provide the scientists in Himalaya or similar data-deficient extreme environments with an option to use freely available remotely observed Ts products in their models to fill-up the spatiotemporal data gaps related to in situ monitoring at daily resolution. Substituting Ta by Ts as input in various geophysical models can even improve the model accuracy as using spatially continuous satellite derived Ts in place of discrete in situ Ta extrapolated to different elevations using a constant lapse rate can provide more realistic estimates. 

  • 21.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martín-Torres, F. Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Revisiting enigmatic Martian slope streaks2019In: Earth Space and Science News - Editors Vox, Vol. 100Article in journal (Other academic)
  • 22.
    Cockell, Charles S.
    et al.
    UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
    McMahon, Sean
    UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
    Lim, Darlene S.S.
    NASA Ames Research Center, Moffett Field, USA.
    Rummel, John
    SETI Institute, Friday Harbor, USA.
    Stevens, Adam
    UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
    Hughes, Scott S.
    Dept. of Geosciences, Idaho State University, Pocatello, USA.
    Nawotniak, Shannon E. Kobs
    Dept. of Geosciences, Idaho State University, Pocatello, USA.
    Brady, Allyson L.
    School of Geography and Earth Sciences, McMaster University, Hamilton, Canada.
    Marteinsson, Viggo
    School of Geography and Earth Sciences, McMaster University, Hamilton, Canada.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh,Edinburgh, UK. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Armilla, Spain.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (CSIC-INTA), Madrid, Spain.
    Harrison, Jesse
    Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku, Finland.
    Sample Collection and Return from Mars: Optimising Sample Collection Based on the Microbial Ecology of Terrestrial Volcanic Environments2019In: Space Science Reviews, ISSN 0038-6308, E-ISSN 1572-9672, Vol. 215, no 7, article id 44Article, review/survey (Refereed)
    Abstract [en]

    With no large-scale granitic continental crust, all environments on Mars are fundamentally derived from basaltic sources or, in the case of environments such as ices, evaporitic, and sedimentary deposits, influenced by the composition of the volcanic crust. Therefore, the selection of samples on Mars by robots and humans for investigating habitability or testing for the presence of life should be guided by our understanding of the microbial ecology of volcanic terrains on the Earth. In this paper, we discuss the microbial ecology of volcanic rocks and hydrothermal systems on the Earth. We draw on microbiological investigations of volcanic environments accomplished both by microbiology-focused studies and Mars analog studies such as the NASA BASALT project. A synthesis of these data emphasises a number of common patterns that include: (1) the heterogeneous distribution of biomass and diversity in all studied materials, (2) physical, chemical, and biological factors that can cause heterogeneous microbial biomass and diversity from sub-millimetre scales to kilometre scales, (3) the difficulty of a priori prediction of which organisms will colonise given materials, and (4) the potential for samples that are habitable, but contain no evidence of a biota. From these observations, we suggest an idealised strategy for sample collection. It includes: (1) collection of multiple samples in any given material type (∼9 or more samples), (2) collection of a coherent sample of sufficient size (∼10 cm3∼10 cm3) that takes into account observed heterogeneities in microbial distribution in these materials on Earth, and (3) collection of multiple sample suites in the same material across large spatial scales. We suggest that a microbial ecology-driven strategy for investigating the habitability and presence of life on Mars is likely to yield the most promising sample set of the greatest use to the largest number of astrobiologists and planetary scientists.

  • 23.
    G. Trainer, Melissa
    et al.
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Wong, Michael H.
    Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI, USA.
    McConnochie, Timothy H.
    University of Maryland, College Park, MD, USA.
    Franz, Heather B.
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Atreya, Sushil K.
    Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI, USA.
    Conrad, Pamela G.
    Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC, USA.
    Lefèvre, Franck
    LATMOS, CNRS, Sorbonne Université, UVSQ, Paris, France.
    Mahaffy, Paul R.
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Malespin, Charles A.
    NASA Goddard Space Flight Center, Greenbelt, MD, USA.
    Manning, Heidi L.K.
    College of Arts and Sciences, Misericordia University, Dallas, PA, USA.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC‐UGR), Granada, Spain.
    Martínez, Germán M.
    Lunar and Planetary Institute, Universities Space Research Association, Houston, TX, USA. Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI, USA.
    McKay, Christopher P.
    NASA Ames Research Center, Moffett Field, CA, USA.
    Navarro‐González, Rafael
    Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Ciudad de México, Mexico.
    Retortillo, Álvaro Vicente
    Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI, USA.
    Webster, Christopher R.
    NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA‐CSIC), Torrejón de Ardoz, Madrid, Spain.
    Seasonal Variations in Atmospheric Composition as Measured in Gale Crater, Mars2019In: Journal of Geophysical Research - Planets, ISSN 2169-9097, E-ISSN 2169-9100, Vol. 124, no 11, p. 3000-3024Article in journal (Refereed)
    Abstract [en]

    The Sample Analysis at Mars (SAM) instrument onboard the Mars Science Laboratory Curiosity rover measures the chemical composition of major atmospheric species (CO2, N240Ar, O2, and CO) through a dedicated atmospheric inlet. We report here measurements of volume mixing ratios in Gale Crater using the SAM quadrupole mass spectrometer, obtained over a period of nearly 5 years (3 Mars years) from landing. The observation period spans the northern summer of MY 31 and solar longitude (LS) of 175° through spring of MY 34, LS = 12°. This work expands upon prior reports of the mixing ratios measured by SAM QMS in the first 105 sols of the mission. The SAM QMS atmospheric measurements were taken periodically, with a cumulative coverage of four or five experiments per season on Mars. Major observations include the seasonal cycle of CO2, N2, and Ar, which lags approximately 20–40° of LS behind the pressure cycle driven by CO2 condensation and sublimation from the winter poles. This seasonal cycle indicates that transport occurs on faster timescales than mixing. The mixing ratio of O2 shows significant seasonal and interannual variability, suggesting an unknown atmospheric or surface process at work. The O2 measurements are compared to several parameters, including dust optical depth and trace CH4 measurements by Curiosity. We derive annual mean volume mixing ratios for the atmosphere in Gale Crater: CO2 = 0.951 (±0.003), N2 = 0.0259 (±0.0006), 40Ar = 0.0194 (±0.0004), O2 = 1.61 (±0.09) x 103, and CO = 5.8 (±0.8) x 104.

  • 24.
    Mathanlal, Thasshwin
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Bhardwaj, Anshuman
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Self-Sustainable Monitoring Station for Extreme Environments (S3ME2): Design and validation2019In: 2018 Second International Conference on Green Computing and Internet of Things (ICGCIoT), IEEE, 2019, p. 240-245Conference paper (Refereed)
    Abstract [en]

    We describe the development of a robust, self-sustainable, versatile environmental monitoring station, the S3ME2, with a multitude of sensors capable of operating in extreme environments (from cold arid sub-arctic regions to hot deserts and high-altitude mountain terrains), providing realtime quality data of critical climate and geophysical parameters for a wide field of research such as pressure, surface and subsurface temperature and humidity, magnetic field and seismic activity. The dedicated communication modem utilizes IoT technology and can deliver this data from remote regions. The S3ME2 has been designed as a low-cost instrument to facilitate the production of multiple units. During the pilot phase, it has demonstrated continuous operability for up to 6 months, including survival during extremely cold, snowy, and low insolation, and low wind periods in the Sub-Arctic region. With its robust design, S3ME2 exploits the use of renewable sources of energy such as solar and wind power to power the system. The S3ME2 has also been designed from a modular point of view with commercial off the shelf components (COTS) and open source hardware, considering long term operability of the station. The sensor modules can be easily added, replaced, or upgraded such that a stable functioning of the system is guaranteed.

  • 25.
    Mathanla, Thasshwin
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Bhardwaj, Anshuman
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Vakkada Ramachandran, Abhilash
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (CSIC-INTA), Madrid, Spain.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    Cockell, Charles
    UK Centre of Astrobiology, SUPA, School of Physics and Astronomy, University of Edinburgh, Edinburgh, Midlothian, UK.
    Paling, Sean
    Boulby Underground Laboratory, Boulby, UK.
    Edwards, Tom
    Boulby Underground Laboratory, Boulby, UK.
    Subsurface robotic exploration for geomorphology, astrobiology and mining during MINAR6 campaign, Boulby Mine, UK: part I (Rover development)2019In: International Journal of Astrobiology, ISSN 1473-5504, E-ISSN 1475-3006Article in journal (Refereed)
    Abstract [en]

    Autonomous exploration requires the use of movable platforms that carry a payload of instruments with a certain level of autonomy and communication with the operators. This is particularly challenging in subsurface environments, which may be more dangerous for human access and where communication with the surface is limited. Subsurface robotic exploration, which has been to date very limited, is interesting not only for science but also for cost-effective industrial exploitation of resources and safety assessments in mines. Furthermore, it has a direct application to exploration of extra-terrestrial subsurface environments of astrobiological and geological significance such as caves, lava tubes, impact or volcanic craters and subglacial conduits, for deriving in-situ mineralogical resources and establishing preliminary settlements. However, the technological solutions are generally tailor-made and are therefore considered as costly, fragile and environment-specific, further hindering their extensive and effective applications. To demonstrate the advantages of rover exploration for a broad-community, we have developed KORE (KOmpact Rover for Exploration); a low-cost, re-usable, rover multi-purpose platform. The rover platform has been developed as a technological demonstration for extra-terrestrial subsurface exploration and terrestrial mining operations pertaining to geomorphological mapping, environmental monitoring, gas leak detections and search and rescue operations in case of an accident. The present paper, the first part of a series of two, focuses on describing the development of a robust rover platform to perform dedicated geomorphological, astrobiological and mining tasks. KORE was further tested in the Mine Analogue Research 6 (MINAR6) campaign during September 2018 in the Boulby mine (UK), the second deepest potash mine in Europe at a subsurface depth of 1.1 km, the results of which will be presented in the second paper of this series. KORE is a large, semi-autonomous rover weighing 160 kg with L × W × H dimensions 1.2 m × 0.8 m × 1 m and a payload carrying capacity of 100 kg using 800 W traction power that can power to a maximum speed of 8.4 km h−1. The rover can be easily dismantled in three parts facilitating its transportation to any chosen site of exploration. Presently, the main scientific payloads on KORE are: (1) a three-dimensional mapping camera, (2) a methane detection system, (3) an environmental station capable of monitoring temperature, relative humidity, pressure and gases such as NO2, SO2, H2S, formaldehyde, CO, CO2, O3, O2, volatile organic compounds and particulates and (4) a robotic arm. Moreover, the design of the rover allows for integration of more sensors as per the scientific requirements in future expeditions. At the MINAR6 campaign, the technical readiness of KORE was demonstrated during 6 days of scientific research in the mine, with a total of 22 h of operation.

  • 26.
    Cockell, Charles S.
    et al.
    UK Centre for Astrobiology, SUPA, School of Physics and Astronomy, University of Edinburgh, Edinburgh, Midlothian, UK.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. UK Centre for Astrobiology, SUPA, School of Physics and Astronomy, University of Edinburgh, Edinburgh, Midlothian, UK; Instituto Andaluz de Ciencias de la Tierra (UGR-CSIC), Granada, Spain .
    Zorzano, Maria-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (CSIC-INTA), Torrejon de Ardoz, 28850 Madrid, Spain.
    Bhardwaj, Anshuman
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Soria-Salinas, Álvaro
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Mathanla, Thasshwin
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Israel Nazarious, Miracle
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Vakkada Ramachandran, Abhilash
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Suckling, Barbara
    Boulby Underground Laboratory, Boulby, UK.
    Subsurface scientific exploration of extraterrestrial environments (MINAR 5): analogue science, technology and education in the Boulby Mine, UK2019In: International Journal of Astrobiology, ISSN 1473-5504, E-ISSN 1475-3006, Vol. 18, no 2, p. 157-182Article in journal (Refereed)
    Abstract [en]

    The deep subsurface of other planetary bodies is of special interest for robotic and human exploration. The subsurface provides access to planetary interior processes, thus yielding insights into planetary formation and evolution. On Mars, the subsurface might harbour the most habitable conditions. In the context of human exploration, the subsurface can provide refugia for habitation from extreme surface conditions. We describe the fifth Mine Analogue Research (MINAR 5) programme at 1 km depth in the Boulby Mine, UK in collaboration with Spaceward Bound NASA and the Kalam Centre, India, to test instruments and methods for the robotic and human exploration of deep environments on the Moon and Mars. The geological context in Permian evaporites provides an analogue to evaporitic materials on other planetary bodies such as Mars. A wide range of sample acquisition instruments (NASA drills, Small Planetary Impulse Tool (SPLIT) robotic hammer, universal sampling bags), analytical instruments (Raman spectroscopy, Close-Up Imager, Minion DNA sequencing technology, methane stable isotope analysis, biomolecule and metabolic life detection instruments) and environmental monitoring equipment (passive air particle sampler, particle detectors and environmental monitoring equipment) was deployed in an integrated campaign. Investigations included studying the geochemical signatures of chloride and sulphate evaporitic minerals, testing methods for life detection and planetary protection around human-tended operations, and investigations on the radiation environment of the deep subsurface. The MINAR analogue activity occurs in an active mine, showing how the development of space exploration technology can be used to contribute to addressing immediate Earth-based challenges. During the campaign, in collaboration with European Space Agency (ESA), MINAR was used for astronaut familiarization with future exploration tools and techniques. The campaign was used to develop primary and secondary school and primary to secondary transition curriculum materials on-site during the campaign which was focused on a classroom extra vehicular activity simulation.

  • 27.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Ramírez Luque, Juan Antonio
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    UAV Imaging of a Martian Brine Analogue Environment in a Fluvio-Aeolian Setting2019In: Remote Sensing, ISSN 2072-4292, E-ISSN 2072-4292, Vol. 11, no 18, article id 2104Article in journal (Refereed)
    Abstract [en]

    Understanding extraterrestrial environments and landforms through remote sensing and terrestrial analogy has gained momentum in recent years due to advances in remote sensing platforms, sensors, and computing efficiency. The seasonal brines of the largest salt plateau on Earth in Salar de Uyuni (Bolivian Altiplano) have been inadequately studied for their localized hydrodynamics and the regolith volume transport across the freshwater-brine mixing zones. These brines have recently been projected as a new analogue site for the proposed Martian brines, such as recurring slope lineae (RSL) and slope streaks. The Martian brines have been postulated to be the result of ongoing deliquescence-based salt-hydrology processes on contemporary Mars, similar to the studied Salar de Uyuni brines. As part of a field-site campaign during the cold and dry season in the latter half of August 2017, we deployed an unmanned aerial vehicle (UAV) at two sites of the Salar de Uyuni to perform detailed terrain mapping and geomorphometry. We generated high-resolution (2 cm/pixel) photogrammetric digital elevation models (DEMs) for observing and quantifying short-term terrain changes within the brines and their surroundings. The achieved co-registration for the temporal DEMs was considerably high, from which precise inferences regarding the terrain dynamics were derived. The observed average rate of bottom surface elevation change for brines was ~1.02 mm/day, with localized signs of erosion and deposition. Additionally, we observed short-term changes in the adjacent geomorphology and salt cracks. We conclude that the transferred regolith volume via such brines can be extremely low, well within the resolution limits of the remote sensors that are currently orbiting Mars, thereby making it difficult to resolve the topographic relief and terrain perturbations that are produced by such flows on Mars. Thus, the absence of observable erosion and deposition features within or around most of the proposed Martian RSL and slope streaks cannot be used to dismiss the possibility of fluidized flow within these features

  • 28.
    Wang, Jianfeng
    et al.
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Fonseca, Ricardo
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Rutledge, Kendall
    Novia University of Applied Sciences, Vaasa, Finland.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    Yu, Jun
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Weather Simulation Uncertainty Estimation Using Bayesian Hierarchical Models2019In: Journal of Applied Meteorology and Climatology, ISSN 1558-8424, E-ISSN 1558-8432, Vol. 58, no 3, p. 585-603Article in journal (Refereed)
    Abstract [en]

    Estimates of the uncertainty of model output fields (e.g., 2-m temperature, surface radiation fluxes, or wind speed) are of great value to the weather and climate communities. The traditional approach for the uncertainty estimation is to conduct an ensemble of simulations where the model configuration is perturbed and/or different models are considered. This procedure is very computationally expensive and may not be feasible, in particular for higher-resolution experiments. In this paper, a new method based on Bayesian hierarchical models (BHMs) that requires just one model run is proposed. It is applied to the Weather Research and Forecasting (WRF) Model’s 2-m temperature in the Botnia–Atlantica region in Scandinavia for a 10-day period in the winter and summer seasons. For both seasons, the estimated uncertainty using the BHM is found to be comparable to that obtained from an ensemble of experiments in which different planetary boundary layer (PBL) schemes are employed. While WRF-BHM is not capable of generating the full set of products obtained from an ensemble of simulations, it can be used to extract commonly used diagnostics including the uncertainty estimation that is the focus of this work. The methodology proposed here is fully general and can easily be extended to any other output variable and numerical model.

  • 29.
    Escamilla-Roa, Elizabeth
    et al.
    Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR).
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR).
    Sainz-Díaz, C. Ignacio
    Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR).
    Adsorption of methane and CO2 onto olivine surfaces in Martian dust conditions2018In: Planetary and Space Science, ISSN 0032-0633, E-ISSN 1873-5088, Vol. 153, p. 163-171Article in journal (Refereed)
    Abstract [en]

    Methane has been detected on all planets of our Solar System, and most of the larger moons, as well as in dwarf-planets like Pluto and Eric. The presence of this molecule in rocky planets is very interesting because its presence in the Earth's atmosphere is mainly related to biotic processes. Space instrumentation in orbiters around Mars has detected olivine on the Martian soil and dust. On the other hand the measurements of methane from the Curiosity rover report detection of background levels of atmospheric methane with abundance that is lower than model estimates of ultraviolet degradation of accreted interplanetary dust particles or carbonaceous chondrite material. Additionally, elevated levels of methane about this background have been observed implying that Mars is episodically producing methane from an additional unknown source, making the reasons of these temporal fluctuations of methane a hot topic in planetary research. The goal of this study is to investigate at atomic level the interactions during the adsorption processes of methane and other Mars atmospheric species (CO2, H2O) on forsterite surfaces, through electronic structure calculations based on the Density Functional Theory (DFT). We propose two models to simulate the interaction of adsorbates with the surface of dust mineral, such as binary mixtures (5CH4+5H2O/5CH4+5CO2) and as a semi-clathrate adsorption. We have obtained interesting results of the adsorption process in the mixture 5CH4+5CO2. Associative and dissociative adsorptions were observed for water and CO2 molecules. The methane molecules were only trapped and held by water or CO2 molecules. In the dipolar surface, the adsorption of CO2 molecules produced new species: one CO from a CO2 dissociation, and, two CO2 molecules chemisorbed to mineral surface forming a carbonate group. Our results suggest that CO2 has a strong interaction with the mineral surface when methane is present. These results could be confirmed after the analysis of the data from the upcoming remote and in-situ observations on Mars, as those to be performed by instruments on the ESA's ExoMars Trace Gas Orbiter and ExoMars rover.

  • 30.
    Webster, Christopher R.
    et al.
    NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra, Granada.
    Zorzano, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiologia, Instituto National de Tecnica Aerospacial, Madrid.
    Vasavada, Ashwin R
    NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA.
    Background levels of methane in Mars' atmosphere show strong seasonal variations2018In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 360, no 6393, p. 1093-1096Article in journal (Refereed)
    Abstract [en]

    Variable levels of methane in the martian atmosphere have eluded explanation partly because the measurements are not repeatable in time or location. We report in situ measurements at Gale crater made over a 5-year period by the Tunable Laser Spectrometer on the Curiosity rover. The background levels of methane have a mean value 0.41 ± 0.16 parts per billion by volume (ppbv) (95% confidence interval) and exhibit a strong, repeatable seasonal variation (0.24 to 0.65 ppbv). This variation is greater than that predicted from either ultraviolet degradation of impact-delivered organics on the surface or from the annual surface pressure cycle. The large seasonal variation in the background and occurrences of higher temporary spikes (~7 ppbv) are consistent with small localized sources of methane released from martian surface or subsurface reservoirs.

  • 31.
    Sam, Lydia
    et al.
    Institut für Kartographie, Technische Universität Dresden.
    Bhardwaj, Anshuman
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Kumar, Rajesh
    Department of Environmental Science, Sharda University.
    Buchroithner, Manfred F.
    Institut für Kartographie, Technische Universität Dresden.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Armilla, Granada .
    Heterogeneity in topographic control on velocities of Western Himalayan glaciers2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, no 1, article id 12843Article in journal (Refereed)
    Abstract [en]

    Studies of the seasonal and annual patterns of glacier velocities improve our understanding of the ice volume, topography, responses to climate change, and surge events of glaciers. Such studies are especially relevant and equally rare for the Himalayan glaciers, which supply many rivers that sustain some of the most heavily populated mountainous regions in the world. In particular, the control of the hypsometric distribution of geomorphometric parameters, such as slope, aspect, and curvature, on the dynamics of Himalayan glaciers have never been studied so far, at the river basin scale. Here, we present the degree to which topographic and hypsometric parameters affect the seasonal and annual average flow velocities of 112 glaciers in the Baspa River basin in the Western Indian Himalaya by analysing Global Land Ice Velocity Extraction from Landsat 8 (GoLIVE) datasets for the years 2013–2017. We observe, (i) significant heterogeneity in topographic controls on the velocities of these glaciers, (ii) elevation and the seasons play important roles in regulating the degree to which morphometric parameters (slope, aspect, and curvature) affect these velocities, (iii) a possible polythermal regime promoting both sliding and deformational forms of motion in a majority of these glaciers, and (iv) a detailed analysis of complex topographic controls within various elevation zones using a novel hypso-morphometric approach. These findings can help us to better model the dynamics of Himalayan glaciers and their responses to the future climatic scenarios. The inferences also suggest the need to incorporate dynamic topography in glacio-hydrological models in the wake of constant glacial evolutions.

  • 32.
    Lasue, J.
    et al.
    Université de Toulouse, Toulouse, France.
    Cousin, A.
    Université de Toulouse, Toulouse, France.
    Meslin, P.Y
    Université de Toulouse,Toulouse, France.
    Mangold, N.
    Université de Nantes, Nantes, France.
    Wiens, R.C
    Los Alamos National Laboratory, Los Alamos, NM, USA.
    Berger, G.
    Université de Toulouse,Toulouse, France.
    Dehouck, E.
    Université de Lyon, Villeurbanne, France.
    Forni, O.
    Université de Toulouse,Toulouse, France.
    Goetz, W.
    Max‐Planck‐Institut für Sonnensystemforschung, Göttingen, Germany.
    Gasnault, O.
    Université de Toulouse,Toulouse, France.
    Rapin, W.
    California Institute of Technology, Pasadena, CA, USA.
    Schroeder, S.
    German Aerospace Center (DLR), Institut für Optische Sensorsysteme, Berlin‐Adlershof, Germany.
    Ollila, A.
    Los Alamos National Laboratory, Los Alamos, NM, USA.
    Johnson, J.
    Johns Hopkins University APL, Laurel, MD, USA.
    Le Mouélic, S.
    Université de Nantes, Nantes, France.
    Maurice, S.
    Université de Toulouse, Toulouse, France.
    Anderson, R.
    USGS, Flagstaff, AZ, USA.
    Blaney, D.
    NASA JPL, Pasadena, CA, USA.
    Clark, B.
    Space Science Institute, Boulder, CO, USA.
    Clegg, S.M
    Los Alamos National Laboratory, Los Alamos, NM, USA.
    D'Uston, C.
    Université de Toulouse,Toulouse, France.
    Fabre, C.
    Lorraine University, Vandoeuvre, France.
    Lanza, N.
    Los Alamos National Laboratory, Los Alamos, NM, USA.
    Madsen, M.B
    Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Melikechi, N.
    University of Massachusetts Lowell, Lowell, MA, USA.
    Newsom, H.
    University of New Mexico, Albuquerque, NM, USA.
    Sautter, V.
    Muséum d'Histoire Naturelle, Paris, France.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Spain.
    Martian Eolian Dust Probed by ChemCam2018In: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 45, no 20, p. 10968-10977Article in journal (Refereed)
    Abstract [en]

    The ubiquitous eolian dust on Mars plays important roles in the current sedimentary and atmospheric processes of the planet. The ChemCam instrument retrieves a consistent eolian dust composition at the submillimeter scale from every first laser shot on Mars targets. Its composition presents significant differences with the Aeolis Palus soils and the Bagnold dunes as it contains lower CaO and higher SiO2. The dust FeO and TiO2contents are also higher, probably associated with nanophase oxide components. The dust spectra show the presence of volatile elements (S and Cl), and the hydrogen content is similar to Bagnold sands but lower than Aeolis Palus soils. Consequently, the dust may be a contributor to the amorphous component of soils, but differences in composition indicate that the two materials are not equivalent.

  • 33.
    Fonseca, Ricardo
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC).
    Martín-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR).
    Planetary Boundary Layer and Circulation Dynamics at Gale Crater, Mars2018In: Icarus (New York, N.Y. 1962), ISSN 0019-1035, E-ISSN 1090-2643, Vol. 302, p. 537-559Article in journal (Refereed)
    Abstract [en]

    The Mars implementation of the Planet Weather Research and Forecasting (PlanetWRF) model, MarsWRF, is used here to simulate the atmospheric conditions at Gale Crater for different seasons during a period coincident with the Curiosity rover operations. The model is first evaluated with the existing single-point observations from the Rover Environmental Monitoring Station (REMS), and is then used to provide a larger scale interpretation of these unique measurements as well as to give complementary information where there are gaps in the measurements.

    The variability of the planetary boundary layer depth may be a driver of the changes in the local dust and trace gas content within the crater. Our results show that the average time when the PBL height is deeper than the crater rim increases and decreases with the same rate and pattern as Curiosity's observations of the line-of-sight of dust within the crater and that the season when maximal (minimal) mixing is produced is Ls 225°-315° (Ls 90°-110°). Thus the diurnal and seasonal variability of the PBL depth seems to be the driver of the changes in the local dust content within the crater. A comparison with the available methane measurements suggests that changes in the PBL depth may also be one of the factors that accounts for the observed variability, with the model results pointing towards a local source to the north of the MSL site.

    The interaction between regional and local flows at Gale crater is also investigated assuming that the meridional wind, the dynamically important component of the horizontal wind at Gale, anomalies with respect to the daily mean can be approximated by a sinusoidal function as they typically oscillate between positive (south to north) and negative (north to south) values that correspond to upslope/downslope or downslope/upslope regimes along the crater rim and Mount Sharp slopes and the dichotomy boundary. The smallest magnitudes are found in the northern crater floor in a region that comprises Bradbury Landing, in particular at Ls 90° when they are less than 1 m s−1, indicating very little lateral mixing with outside air. The largest amplitudes occur in the south-western portions of the crater where they can exceed 20 m s−1. Should the slope flows along the crater rims interact with the dichotomy boundary flow, which is more likely at Ls 270° and very unlikely at Ls 90°, they are likely to interact constructively for a few hours from late evening to nighttime (∼17-23 LMST) and from pre-dawn early morning (∼5-11 LMST) hours at the norther crater rim and destructively at night (∼22-23 LMST) and in the morning (∼10-11 LMST) at the southern crater rim.

    We conclude that a better understanding of the PBL and circulation dynamics has important implications for the variability of the concentration of dust, non-condensable and trace gases at the bottom of other craters on Mars as mixing with outside air can be achieved vertically, through changes in the PBL depth, and laterally, by the transport of air into and out of the crater.

  • 34.
    Korablev, O.
    et al.
    Space Research Institute (IKI)MoscowRussia.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR)GranadaSpain.
    Zorzano, Maria-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de AstrobiologíaINTA-CSICMadridSpain.
    The Atmospheric Chemistry Suite (ACS) of Three Spectrometers for the ExoMars 2016 Trace Gas Orbiter2018In: Space Science Reviews, ISSN 0038-6308, E-ISSN 1572-9672, Vol. 247, no 1, article id 7Article in journal (Refereed)
    Abstract [sv]

    The Atmospheric Chemistry Suite (ACS) package is an element of the Russian contribution to the ESA-Roscosmos ExoMars 2016 Trace Gas Orbiter (TGO) mission. ACS consists of three separate infrared spectrometers, sharing common mechanical, electrical, and thermal interfaces. This ensemble of spectrometers has been designed and developed in response to the Trace Gas Orbiter mission objectives that specifically address the requirement of high sensitivity instruments to enable the unambiguous detection of trace gases of potential geophysical or biological interest. For this reason, ACS embarks a set of instruments achieving simultaneously very high accuracy (ppt level), very high resolving power (>10,000) and large spectral coverage (0.7 to 17 μm—the visible to thermal infrared range). The near-infrared (NIR) channel is a versatile spectrometer covering the 0.7–1.6 μm spectral range with a resolving power of ∼20,000. NIR employs the combination of an echelle grating with an AOTF (Acousto-Optical Tunable Filter) as diffraction order selector. This channel will be mainly operated in solar occultation and nadir, and can also perform limb observations. The scientific goals of NIR are the measurements of water vapor, aerosols, and dayside or night side airglows. The mid-infrared (MIR) channel is a cross-dispersion echelle instrument dedicated to solar occultation measurements in the 2.2–4.4 μm range. MIR achieves a resolving power of >50,000. It has been designed to accomplish the most sensitive measurements ever of the trace gases present in the Martian atmosphere. The thermal-infrared channel (TIRVIM) is a 2-inch double pendulum Fourier-transform spectrometer encompassing the spectral range of 1.7–17 μm with apodized resolution varying from 0.2 to 1.3 cm−1. TIRVIM is primarily dedicated to profiling temperature from the surface up to ∼60 km and to monitor aerosol abundance in nadir. TIRVIM also has a limb and solar occultation capability. The technical concept of the instrument, its accommodation on the spacecraft, the optical designs as well as some of the calibrations, and the expected performances for its three channels are described.

  • 35.
    Dirri, Fabrizio
    et al.
    IAPS-INAF, Via Fosso del Cavaliere 100 Rome, 00133, Italy.
    Palomba, Ernesto
    IAPS-INAF, Via Fosso del Cavaliere 100 Rome, 00133, Italy.
    Longobardo, Andrea
    IAPS-INAF, Via Fosso del Cavaliere 100 Rome, 00133, Italy.
    Biondi, David
    IAPS-INAF, Via Fosso del Cavaliere 100 Rome, 00133, Italy.
    Boccaccini, Angelo
    IAPS-INAF, Via Fosso del Cavaliere 100 Rome, 00133, Italy.
    Galiano, Anna
    IAPS-INAF, Via Fosso del Cavaliere 100 Rome, 00133, Italy.
    Zampetti, Emiliano
    IIA-CNR, via Salaria km 29,300 Monterotondo Rome, Italy.
    Saggin, Bortolino
    Politecnico di Milano, Polo Territoriale di Lecco Lecco, Italy.
    Scaccabarozzi, Diego
    Politecnico di Milano, Polo Territoriale di Lecco Lecco, Italy.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    VISTA instrument: a PCM-based sensor for organics and volatiles characterization by using Thermogravimetric technique2018Conference paper (Refereed)
    Abstract [en]

    VISTA (Volatile In Situ Thermogravimetry Analyser) is a µ-Thermogravimeter sensor developed by Consortium of Italian Institutes. ThermoGravimetric Analysis (TGA) is a widely used technique to monitor thermal processes involving volatile compounds, e.g. deposition/sublimation and absorption/ desorption. The instrument core is composed by a Piezoelectric Crystal Microbalance (PCM), equipped with built-in heater and built-in temperature sensor, and provided of its own Proximity Electronics (PE). The PCM oscillation frequency linearly depends on the mass deposited on its sensible area (according to Sauerbrey equation) while the PCM temperature can be increased by means of integrated heaters. Thus, mass and volatile composition can be inferred by the frequency change and by desorption temperature, respectively. The instrument is divided in two sensor heads: VISTA1, able to monitor outgassing processes in space, and VISTA2, able to reach higher temperatures, studying the dehydration and organics decomposition in minerals in different environmental conditions. An Engineering Model of VISTA1 and a laboratory breadboard of VISTA2 have been developed. Pure organic compounds and contaminant have been characterized by using deposition processes and TGA cycles obtaining some physical-chemical parameters, i.e. enthalpy of sublimation/evaporation, ΔHHsub,evap , deposition rates, kk and vapor pressures, Pvap . The instrument concept, the scientific objectives and the laboratory measurements are explained in this work.

  • 36.
    Fonseca, Ricardo
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada.
    Andersson, Kent
    Swedish Space Corporation, Esrange Space Center, Kiruna.
    Wind Forecasts for Rocket and Balloon Launches at the Esrange Space Center Using the WRF Model2018In: Weather and forecasting, ISSN 0882-8156, E-ISSN 1520-0434, Vol. 33, no 3, p. 813-833Article in journal (Refereed)
    Abstract [en]

    High-altitude balloons and rockets are regularly launched at the Esrange Space Center (ESC) in Kiruna, Sweden, with the aim of retrieving atmospheric data for meteorological and space studies in the Arctic region. Meteorological conditions, particularly wind direction and speed, play a critical role in the decision of whether to go ahead with or postpone a planned launch. Given the lack of high-resolution wind forecasts for this remote region, the Weather Research and Forecasting (WRF) Model is used to downscale short-term forecasts given by the Global Forecast System (GFS) for the ESC for six 5-day periods in the warm, cold, and transition seasons. Three planetary boundary layer (PBL) schemes are considered: the local Mellor-Yamada-Janjic' (MYJ), the nonlocal Yonsei University (YSU), and the hybrid local-nonlocal Asymmetric Convective Model 2 (ACM2). The ACM2 scheme is found to provide the most skillful forecasts. An analysis of the WRF Model output against the launch criteria for two of the most commonly launched vehicles, the sounding rockets Veículo de Sondagem Booster-30 (VSB-30) and Improved Orion, reveals probability of detection (POD) values that always exceeds 60% with the false alarm rate (FAR) generally below 50%. It is concluded that the WRF Model, in its present configuration, can be used to generate useful 5-day wind forecasts for the launches of these two rockets. The conclusions reached here are applicable to similar sites in the Arctic and Antarctic regions.

  • 37.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Department of Environmental Science, Sharda University.
    Singh, Shaktiman
    Department of Environmental Science, Sharda University,.
    Sam, Lydia
    Department of Environmental Science, Sharda University,.
    Joshi, PK
    School of Environmental Sciences, Jawaharlal Nehru University, New Delhi.
    Bhardwaj, Akanksha
    Banaras Hindu University.
    Martín-Torres, Javier F.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR).
    Kumar, Rajesh
    Department of Environmental Science, Sharda University.
    A review on remotely sensed land surface temperature anomaly as an earthquake precursor2017In: International Journal of Applied Earth Observation and Geoinformation, ISSN 0303-2434, Vol. 63, p. 158-166Article in journal (Refereed)
    Abstract [en]

    The low predictability of earthquakes and the high uncertainty associated with their forecasts make earthquakes one of the worst natural calamities, capable of causing instant loss of life and property. Here, we discuss the studies reporting the observed anomalies in the satellite-derived Land Surface Temperature (LST) before an earthquake. We compile the conclusions of these studies and evaluate the use of remotely sensed LST anomalies as precursors of earthquakes. The arrival times and the amplitudes of the anomalies vary widely, thus making it difficult to consider them as universal markers to issue earthquake warnings. Based on the randomness in the observations of these precursors, we support employing a global-scale monitoring system to detect statistically robust anomalous geophysical signals prior to earthquakes before considering them as definite precursors.

  • 38.
    Martín-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    A space rose by another name smells sweeter2017In: New scientist (1971), ISSN 0262-4079, Vol. 233, no 3116, p. 52-54Article in journal (Refereed)
  • 39.
    Soria-Salinas, Álvaro
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, Maria-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sánchez-García-Casarrubios, J.
    Department of Signal and Telecommunication Theory, Universidad Autónoma de Madrid.
    Pérez-Díaz, J-L
    Department of Signal and Telecommunication Theory, Universidad Autónoma de Madrid.
    Vakkada Ramachandran, Abhilash
    Luleå University of Technology.
    A Xenon Mass Gauging through Heat Transfer Modeling for Electric Propulsion Thrusters2017In: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology, ISSN 2010-376X, E-ISSN 2070-3740, Vol. 11, no 1, p. 94-105Article in journal (Refereed)
    Abstract [en]

    The current state-of-the-art methods of mass gauging of Electric Propulsion (EP) propellants in microgravity conditions rely on external measurements that are taken at the surface of the tank. The tanks are operated under a constant thermal duty cycle to store the propellant within a pre-defined temperature and pressure range. We demonstrate using computational fluid dynamics (CFD) simulations that the heat-transfer within the pressurized propellant generates temperature and density anisotropies. This challenges the standard mass gauging methods that rely on the use of time changing skin-temperatures and pressures. We observe that the domes of the tanks are prone to be overheated, and that a long time after the heaters of the thermal cycle are switched off, the system reaches a quasi-equilibrium state with a more uniform density. We propose a new gauging method, which we call the Improved PVT method, based on universal physics and thermodynamics principles, existing TRL-9 technology and telemetry data. This method only uses as inputs the temperature and pressure readings of sensors externally attached to the tank. These sensors can operate during the nominal thermal duty cycle. The improved PVT method shows little sensitivity to the pressure sensor drifts which are critical towards the end-of-life of the missions, as well as little sensitivity to systematic temperature errors. The retrieval method has been validated experimentally with CO2 in gas and fluid state in a chamber that operates up to 82 bar within a nominal thermal cycle of 38 °C to 42 °C. The mass gauging error is shown to be lower than 1% the mass at the beginning of life, assuming an initial tank load at 100 bar. In particular, for a pressure of about 70 bar, just below the critical pressure of CO2, the error of the mass gauging in gas phase goes down to 0.1% and for 77 bar, just above the critical point, the error of the mass gauging of the liquid phase is 0.6% of initial tank load. This gauging method improves by a factor of 8 the accuracy of the standard PVT retrievals using look-up tables with tabulated data from the National Institute of Standards and Technology.

  • 40.
    Smith, M.D.
    et al.
    NASA Goddard Space Flight Center, Greenbelt.
    Zorzano Mier, Maria-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Lemmon, Mark T.
    Department of Atmospheric Sciences , Texas A&M University.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Mendaza de Cal, Maria Teresa
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Aerosol optical depth as observed by the Mars Science Laboratory REMS UV photodiodes2017Conference paper (Other academic)
  • 41.
    Ullán, Aurora
    et al.
    Departamento de Teoría de la Señal y Comunicaciones, Escuela Politécnica Superior , Universidad de Alcalá, Madrid.
    Zorzano Mier, Maria-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Valentin-Serrano, Patricia
    nstituto Andaluz de Ciencias de la Tierra (CSIC - UGR), Granada.
    Kahanpää, Henrik
    Finnish Meteorological Institute, Helsinki.
    Harri, Ari-Matti
    Finnish Meteorological Institute, Helsinki.
    Gómez-Elvira, Javier
    Centro de Astrobiologí a (CSIC-INTA), Torrejón de Ardoz, Madrid.
    Navarro, Sara
    Centro de Astrobiología (CSIC - INTA), Torrejón de Ardoz, Madrid.
    Analysis of wind-induced dynamic pressure fluctuations during one and a half Martian years at Gale Crater2017In: Icarus (New York, N.Y. 1962), ISSN 0019-1035, E-ISSN 1090-2643, Vol. 288, p. 78-87Article in journal (Refereed)
    Abstract [en]

    The Rover Environmental Monitoring Station (REMS) instrument on-board the Mars Science Laboratory (MSL) has acquired unprecedented measurements of key environmental variables at the base of Gale Crater. The pressure measured by REMS shows modulations with a very structured pattern of short-time scale (of the order of seconds to several minutes) mild fluctuations (typically up to 0.2 Pa at daytime and 1 Pa at night-time). These dynamic pressure oscillations are consistent with wind, air and ground temperature modulations measured simultaneously by REMS. We detect the signals of a repetitive pattern of upslope/downslope winds, with maximal speeds of about 21 m/s, associated with thermal changes in the air and surface temperatures, that are initiated after sunset and finish with sunrise proving that Gale, a 4.5 km deep impact crater, is an active Aeolian environment. At nighttime topographic slope winds are intense with maximal activity from 17:00 through 23:00 Local Mean Solar Time, and simultaneous changes of surface temperature are detected. During the day, the wind modulations are related to convection of the planetary boundary layer, winds are softer with maximum wind speed of about 14 m/s. The ground temperature is modulated by the forced convection of winds, with amplitudes between 0.2 K and 0.5 K, and the air temperatures fluctuate with amplitudes of about 2 K. The analysis of more than one and a half Martian years indicates the year-to-year repeatability of these environmental phenomena. The wind pattern minimizes at the beginning of the south hemisphere winter (Ls 90) season and maximizes during late spring and early summer (Ls 270). The procedure that we present here is a useful tool to investigate in a semi-quantitative way the winds by: i) filling both seasonal and diurnal gaps where wind measurements do not exist, ii) providing an alternative way for comparisons through different measuring principia and, iii) filling the gap of observation of short time-wind variability, where the REMS wind-sensor is blind

  • 42.
    Kahanpää, Henrik
    et al.
    Finnish Meteorological Institute, Helsinki.
    Newman, C.
    Ashima Research Inc.
    Moores, John E.
    Earth and Space Science and Engineering , York University.
    Zorzano Mier, Maria-Paz
    Centro de Astrobiología (CSIC - INTA), Torrejón de Ardoz, Madrid.
    Navarro, Sara
    Centro de Astrobiología (CSIC - INTA), Torrejón de Ardoz, Madrid.
    Lepinette, Alain
    Centro de Astrobiología (CSIC - INTA), Torrejón de Ardoz, Madrid.
    Martin-Torres, Javier
    nstituto Andaluz de Ciencias de la Tierra (CSIC - UGR), Granada.
    Valentin-Serrano, Patricia
    nstituto Andaluz de Ciencias de la Tierra (CSIC - UGR), Granada.
    Cantor, Bruce
    Malin Space Science Systems, San Diego.
    Lemmon, Mark T.
    Department of Atmospheric Sciences , Texas A&M University.
    Ullán, Aurora
    Departamento de Teoría de la Señal y Comunicaciones, Escuela Politécnica Superior , Universidad de Alcalá, Madrid.
    Schmidt, W.
    Finnish Meteorological Institute, Helsinki.
    Dust Devils and Convective Vortices Detected by MSL2017Conference paper (Other academic)
  • 43.
    Shekhar, Mayank
    et al.
    Birbal Sahni Institute of Palaeosciences, Lucknow, India.
    Bhardwaj, Anshuman
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Singh, Shaktiman
    Institut für Kartographie, Technische Universität Dresden.
    Ranhotra, Parminder S.
    Birbal Sahni Institute of Palaeosciences, Lucknow, India.
    Bhattacharyya, Amalava
    Birbal Sahni Institute of Palaeosciences, Lucknow, India.
    Pal, Ashish K.
    Birbal Sahni Institute of Palaeosciences, Lucknow, India.
    Roy, Ipsita
    Birbal Sahni Institute of Palaeosciences, Lucknow, India.
    Martín-Torres, F. Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Armilla, Granada, Spain.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), 28850, Torrejón de Ardoz, Madrid, Spain.
    Himalayan glaciers experienced significant mass loss during later phases of little ice age2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, article id 10305Article in journal (Refereed)
    Abstract [en]

    To date, there is a gap in the data about the state and mass balance of glaciers in the climate-sensitive subtropical regions during the Little Ice Age (LIA). Here, based on an unprecedented tree-ring sampling coverage, we present the longest reconstructed mass balance record for the Western Himalayan glaciers, dating to 1615. Our results confirm that the later phase of LIA was substantially briefer and weaker in the Himalaya than in the Arctic and subarctic regions. Furthermore, analysis of the time-series of the mass-balance against other time-series shows clear evidence of the existence of (i) a significant glacial decay and a significantly weaker magnitude of glaciation during the latter half of the LIA; (ii) a weak regional mass balance dependence on either the El Niño-Southern Oscillation (ENSO) or the Total Solar Irradiance (TSI) taken in isolation, but a considerable combined influence of both of them during the LIA; and (iii) in addition to anthropogenic climate change, the strong effect from the increased yearly concurrence of extremely high TSI with El Niño over the past five decades, resulting in severe glacial mass loss. The generated mass balance time-series can serve as a source of reliable reconstructed data to the scientific community.

  • 44.
    Korablev, Oleg I.
    et al.
    Space Research Institute IKI, Moscow.
    Dobrolensky, Yurii
    Space Research Institute IKI, Moscow.
    Evdokimova, Nadezhda
    Space Research Institute IKI, Moscow.
    Fedorova, Anna A.
    Space Research Institute IKI, Moscow.
    Kuzmin, Ruslan O.
    Space Research Institute IKI, Moscow.
    Mantsevich, Sergei N.
    Space Research Institute IKI, Moscow.
    Cloutis, Edward A.
    The University of Winnipeg.
    Carter, John
    Institut d'Astrophysique Spatiale IAS-CNRS/Université Paris Sud Orsay.
    Poulet, Francois
    Institut d'Astrophysique Spatiale IAS-CNRS/Université Paris Sud Orsay.
    Flahaut, Jessica
    Université Lyon 1, ENS-Lyon, CNRS.
    Griffiths, Andrew
    Mullard Space Science Laboratory, University College London, Dorking.
    Gunn, Matthew
    Department of Physics, Aberystwyth University.
    Schmitz, Nicole
    German Aerospace Center DLR, Köln.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, Maria-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Rodianov, Daniil S.
    Space Research Institute IKI, Moscow.
    Vago, Jorge L.
    ESA ESTEC, Noordwijk.
    Stepanov, Alexander V.
    Space Research Institute IKI, Moscow.
    Titov, Andrei Yu.
    Space Research Institute IKI, Moscow.
    Vyazovetsky, Nikita A.
    Space Research Institute IKI, Moscow.
    Trokhimovskiy, Alexander Yu.
    Space Research Institute IKI, Moscow.
    Sapgir, Alexander G.
    Space Research Institute IKI, Moscow.
    Kalinnikov, Yurii K.
    Space Research Institute IKI, Moscow.
    Ivanov, Yurii S.
    Main Astronomical Observatory MAO NASU, Kyiv.
    Shapkin, Alexei A.
    Space Research Institute IKI, Moscow.
    Ivanov, Andrei Yu.
    Space Research Institute IKI, Moscow.
    Infrared Spectrometer for ExoMars: A Mast-Mounted Instrument for the Rover2017In: Astrobiology, ISSN 1531-1074, E-ISSN 1557-8070, Vol. 17, no 6-7, p. 542-564Article in journal (Refereed)
    Abstract [en]

    ISEM (Infrared Spectrometer for ExoMars) is a pencil-beam infrared spectrometer that will measure reflected solar radiation in the near infrared range for context assessment of the surface mineralogy in the vicinity of the ExoMars rover. The instrument will be accommodated on the mast of the rover and will be operated together with the panoramic camera (PanCam), high-resolution camera (HRC). ISEM will study the mineralogical and petrographic composition of the martian surface in the vicinity of the rover, and in combination with the other remote sensing instruments, it will aid in the selection of potential targets for close-up investigations and drilling sites. Of particular scientific interest are water-bearing minerals, such as phyllosilicates, sulfates, carbonates, and minerals indicative of astrobiological potential, such as borates, nitrates, and ammonium-bearing minerals. The instrument has an ∼1° field of view and covers the spectral range between 1.15 and 3.30 μm with a spectral resolution varying from 3.3 nm at 1.15 μm to 28 nm at 3.30 μm. The ISEM optical head is mounted on the mast, and its electronics box is located inside the rover's body. The spectrometer uses an acousto-optic tunable filter and a Peltier-cooled InAs detector. The mass of ISEM is 1.74 kg, including the electronics and harness. The science objectives of the experiment, the instrument design, and operational scenarios are described.

  • 45.
    Mendaza de Cal, Maria Teresa
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Blanco-Ávalos, J.J.
    Universidad Alcalá de Henares (UAH) Dpto. Física y Matemáticas, Campus Científico-Tecnológico (Externo) Alcalá de Henares (Madrid).
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (UGR-CSIC), Avenida de las Palmeras 4, Armilla, Granada, Spain.
    Interplanetary Coronal Mass Ejection effects on thermospheric density as inferred from International Space Station orbital data2017In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 60, no 10, p. 2233-2251Article in journal (Refereed)
    Abstract [en]

    The solar activity induces long term and short term periodical variations in the dynamics and composition of Earth’s atmosphere. The Sun also shows non periodical (i.e., impulsive) activity that reaches the planets orbiting around it. In particular, Interplanetary Coronal Mass Ejections (ICMEs) reach Earth and interact with its magnetosphere and upper neutral atmosphere. Nevertheless, the interaction with the upper atmosphere is not well characterized because of the absence of regular and dedicated in situ measurements at high altitudes; thus, current descriptions of the thermosphere are based on semi empirical models.

    In this paper, we present the total neutral mass densities of the thermosphere retrieved from the orbital data of the International Space Station (ISS) using the General Perturbation Method, and we applied these densities to routinely compiled trajectories of the ISS in low Earth orbit (LEO). These data are explicitly independent of any atmospheric model. Our density values are consistent with atmospheric models, which demonstrates that our method is reliable for the inference of thermospheric density. We have inferred the thermospheric total neutral density response to impulsive solar activity forcing from 2001 to the end of 2006 and determined how solar events affect this response. Our results reveal that the ISS orbital parameters can be used to infer the thermospheric density and analyze solar effects on the thermosphere.

  • 46.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Institut für Kartographie, Technische Universität Dresden.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, Maria-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Fonseca, Ricardo
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martian slope streaks as plausible indicators of transient water activity2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, no 1, article id 7074Article in journal (Refereed)
    Abstract [en]

    Slope streaks have been frequently observed in the equatorial, low thermal inertia and dusty regions of Mars. The reason behind their formation remains unclear with proposed hypotheses for both dry and wet mechanisms. Here, we report an up-to-date distribution and morphometric investigation of Martian slope streaks. We find: (i) a remarkable coexistence of the slope streak distribution with the regions on Mars with high abundances of water-equivalent hydrogen, chlorine, and iron; (ii) favourable thermodynamic conditions for transient deliquescence and brine development in the slope streak regions; (iii) a significant concurrence of slope streak distribution with the regions of enhanced atmospheric water vapour concentration, thus suggestive of a present-day regolith-atmosphere water cycle; and (iv) terrain preferences and flow patterns supporting a wet mechanism for slope streaks. These results suggest a strong local regolith-atmosphere water coupling in the slope streak regions that leads to the formation of these fluidised features. Our conclusions can have profound astrobiological, habitability, environmental, and planetary protection implications

  • 47.
    Soria-Salinas, Álvaro
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano, María Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiologiá (INTA-CSIC), Madrid.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada.
    Microgravity validation for xenon propellant distributions2017Conference paper (Refereed)
    Abstract [en]

    In the current Electric Propulsion era, one of the most relevant propellants is xenon, which is generally stored in supercritical stage. Because of the increase in time of spacecraft lifetime, the amount of propellant stored on-board has been quadrupled in the recent years, and the need of more accurate gauging methods for measuring propellant usage along the missions has become more critical too. Thermal gradients affect the densities distribution of the stored propellants and this turns out to be critical in orbit because of the absence of convection in low-gravity environments. Recently we have proposed a new gauging method (Soria-Salinas, et al., 2017) that relies on the analysis of measurements from existing and operating technology (in TRL 9), i.e., this method does not imply the development of any new technology. This new method, the improved PVT method, improves by a factor 8 the accuracy of the standard PVT retrievals (Soria-Salinas, et al., 2017). A laboratory experimental validation has shown that, for CO2 at a pressure of about 70 bar, just below the critical pressure, the error of the mass retrieval using this new gauging method is only 0.1% of the initial mass at launch. However, for its complete validation, a microgravity study should be performed in order to quantify the effect of thermal gradients under the absence of convection in a low-g environment. The present work describes: 1) the design of a proposed in-flight microgravity validation experiment for a parabolic flight campaign such as those provided by the Airbus A-310 zero-G platform for microgravity research; and 2) comparative studies of the expected xenon density distribution of real size tanks under operation in orbit, through computational fluid dynamics (CFD) and heat transfer calculations.

  • 48.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Singh, Shaktiman
    Institut für Kartographie, Technische Universität Dresden.
    Sam, Lydia
    Institut für Kartographie, Technische Universität Dresden.
    Bhardwaj, Akanksha
    Banaras Hindu University, Varanasi.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Singh, Atar
    Department of Environmental Science, Sharda University.
    Kumar, Rajesh
    Department of Environmental Science, Sharda University.
    MODIS-based estimates of strong snow surface temperature anomaly related to high altitude earthquakes of 20152017In: Remote Sensing of Environment, ISSN 0034-4257, E-ISSN 1879-0704, Vol. 188, p. 1-8Article in journal (Refereed)
    Abstract [en]

    The high levels of uncertainty associated with earthquake prediction render earthquakes some of the worst natural calamities. Here, we present our observations of MODerate resolution Imaging Spectroradiometer (MODIS)-derived Land Surface Temperature (LST) anomaly for earthquakes in the largest tectonically active Himalayan and Andean mountain belts. We report the appearance of fairly detectable pre-earthquake Snow Surface Temperature (SST) anomalies. We use 16 years (2000–2015) of MODIS LST time-series data to robustly conclude our findings for three of the most destructive earthquakes that occurred in 2015 in the high mountains of Nepal, Chile, and Afghanistan. We propose the physical basis behind higher sensitivity of snow towards geothermal emissions. Although the preliminary appearance of SST anomalies and their amplitudes vary, we propose employing a global-scale monitoring system for detecting and studying such spatio-temporal geophysical signals. With the advent of improved remote sensors, we anticipate that such efforts can be another step towards improved earthquake predictions.

  • 49.
    Moyano-Cambero, Carles E.
    et al.
    Institute of Space Sciences (IEEC-CSIC), Campus UAB, Carrer de Can Magrans.
    Trigo-Rodríguez, Josep M.
    Institute of Space Sciences (IEEC-CSIC), Campus UAB, Carrer de Can Magrans.
    Benito, M. Isabel
    Departamento de Estratigrafía-IGEO, Facultad de Ciencias Geológicas, Universidad Complutense de Madrid-CSIC.
    Alonso-Azcárate, Jacinto
    Fac. de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha.
    Lee, Martin R.
    School of Geographical and Earth Sciences, University of Glasgow.
    Mestres, Narcís
    Institut de Cìencia de Materials de Barcelona (ICMAB-CSIC) .
    Martínez-Jiménez, Marina
    Institute of Space Sciences (IEEC-CSIC), Campus UAB, Carrer de Can Magrans.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Fraxedas, Jordi
    Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and the Barcelona Institute of Science and Technology, Campus UAB.
    Petrographic and geochemical evidence for multiphase formation of carbonates in the Martian orthopyroxenite Allan Hills 840012017In: Meteoritics and Planetary Science, ISSN 1086-9379, E-ISSN 1945-5100, Vol. 52, no 6, p. 1030-1047Article in journal (Refereed)
    Abstract [en]

    Martian meteorites can provide valuable information about past environmental conditions on Mars. Allan Hills 84001 formed more than 4 Gyr ago, and owing to its age and long exposure to the Martian environment, and this meteorite has features that may record early processes. These features include a highly fractured texture, gases trapped during one or more impact events or during formation of the rock, and spherical Fe-Mg-Ca carbonates. In this study, we have concentrated on providing new insights into the context of these carbonates using a range of techniques to explore whether they record multiple precipitation and shock events. The petrographic features and compositional properties of these carbonates indicate that at least two pulses of Mg- and Fe-rich solutions saturated the rock. Those two generations of carbonates can be distinguished by a very sharp change in compositions, from being rich in Mg and poor in Fe and Mn, to being poor in Mg and rich in Fe and Mn. Between these two generations of carbonate is evidence for fracturing and local corrosion

  • 50.
    Martín-Torres, Javier
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.