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Design of a Portable Susceptometer With No Electromagnets
(Institute of Electrical and Electronics Engineers (IEEE), 2023-12-04) Rivelles García, Alejandro; Sanz Lluch, María del Mar; Maicas, M.; Mesa, José Luis; Díaz Michelena, M.; Aroca, C.; Ministerio de Ciencia e Innovación (MICINN); European Research Council (ERC)
Magnetic materials characterization usually requires heavy equipment based on electromagnets, which limits their use to the laboratory. The volume of the typical samples is small in order to keep a good uniformity of the applied magnetic field in the sample. This kind of equipment is not appropriate for geological measurements in the field, where portable systems are required and samples have typically a higher volume. Here, we study the limits and applicability of a portable susceptometer device based on strong magnets potentially applicable in geological prospections. A new prototype has been built and tested. The device makes use of Nd–Fe–B magnets and an iron magnetic circuit (MC) to apply the magnetic field to the sample. A quasi-spherical geometry of the MC provides good uniformity of the magnetic field while keeping a moderate measuring volume. The equipment is powered by a 12-V battery and a mechanical design allows the control of the magnetic flux density in the range of approximately 30–130 mT.
Acceso Abierto
Constraints on the Spatial Distribution of Lunar Crustal Magnetic Sources From Orbital Magnetic Field Data
(Advancing Earth and Space Science (AGU), 2024-02-14) Oliveira, Joana S.; Vervelidou, Foteini; Wieczorek, Mark A.; Díaz Michelena, M.; Oliveira, Joana S.; Ministerio de Ciencia e Innovación (MICINN); European Research Council (ERC)
Spacecraft measurements show that the crust of the Moon is heterogeneously magnetized. The sources of these magnetic anomalies are yet not fully understood, with most not being related to known geological structures or processes. Here, we use an inversion methodology that relies on the assumption of unidirectional magnetization, commonly referred to as Parker's method, to elucidate the origin of the magnetic sources by constraining the location and geometry of the underlying magnetization. This method has been used previously to infer the direction of the underlying magnetization but it has not been tested as to whether it can infer the geometry of the source. The performance of the method is here assessed by conducting a variety of tests, using synthetic magnetized bodies of different geometries mimicking the main geological structures potentially magnetized within the lunar crust. Results from our tests show that this method successfully localizes and delineates the two-dimensional surface projection of subsurface three-dimensional magnetized bodies, provided their magnetization is close to unidirectional and the magnetic field data are of sufficient spatial resolution and reasonable signal-to-noise ratio. We applied this inversion method to two different lunar magnetic anomalies, the Mendel-Rydberg impact basin and the Reiner Gamma swirl. For Mendel-Rydberg, our analysis shows that the strongest magnetic sources are located within the basin's inner ring, whereas for Reiner Gamma, the strongest magnetic sources form a narrow dike-like body that emanates from the center of the Marius Hills volcanic complex.
Acceso Abierto
Vector magnetometry to analyse the Caldereta volcano in the canary islands as a possible terrestrial analogue of mars
(Elsevier, 2025-04-07) Díaz Michelena, M.; Losantos, Emma; Rivero, Miguel Ángel; Oliveira, Joana S.; García Monasterio, Óscar; Mansilla, Federico; Melguizo, Ángel; García Bueno, Jose Luis; Salamanca, David; Fernández Romero, S.; Rivero Rodríguez, Miguel Ángel; Oliveira, Joana S.; Ministerio de Ciencia e Innovación (MICINN); European Research Council (ERC)
Volcanoes are typical features of terrestrial planets' surfaces. Among the different geological processes which give rise to volcanoes, hydromagmatic eruptions are of particular importance for the search of extraterrestrial life since they require the presence of water. Phreatomagmatic eruptions on Mars shall resemble those of the Earth. The possibility to perform magnetic surveys on Mars with magnetometers carried by helicopters opens a new scenario to gain more insights on such features. As a natural first step, gathering a database of terrestrial analogue magnetic signatures is desired, prior to magnetic surveys on the Martian surface. In this work we have selected the Caldereta volcano, a phreatomagmatic edifice in Lanzarote Island (Canary Islands), to perform a magnetic survey using on board drones magnetometry. The acquired data will allow to compare future measurements from other similar structures of the “Red Planet”. The survey casts vector magnetic field data generated by the volcanic edifice. Additionally, we suggest a simplified structure that mimics the geomorphology observed, we attribute a magnetization to such structure and develop a mathematical model that computes its sourced magnetic field. Finally, we develop synthetic models of a volcano on Mars which have been preliminarily classified as hydromagmatic taking Caldereta simulated structure as a reference.
Acceso Abierto
Future space experiment platforms for astrobiology and astrochemistry research
(npj Microgravity, 2023-06-12) Elsaesser, Andreas; Burr, David J.; Mabey, Paul; Urso, Riccardo Giovanni; Billi, Daniela; Cockell, Charles S.; Cottin, Hervé; Kish, Adrienne; Leys, Natalie; Van Loon, Jack J. W. A.; Mateo Martí, Eva; Moissl-Eichinger, Christine; Onofri, Silvano; Quinn, Richard C.; Rabbow, Elke; Rettberg, Petra; De la Torre Noetzel, R.; Slenzka, Klaus; Ricco, Antonio J.; De Vera, Jean Pierre; Westall, Frances; de la Torre Noetzel, Maria Rosa; European Space Agency (ESA)
Space experiments are a technically challenging but a scientifically important part of astrobiology and astrochemistry research. The International Space Station (ISS) is an excellent example of a highly successful and long-lasting research platform for experiments in space, that has provided a wealth of scientific data over the last two decades. However, future space platforms present new opportunities to conduct experiments with the potential to address key topics in astrobiology and astrochemistry. In this perspective, the European Space Agency (ESA) Topical Team Astrobiology and Astrochemistry (with feedback from the wider scientific community) identifies a number of key topics and summarizes the 2021 “ESA SciSpacE Science Community White Paper” for astrobiology and astrochemistry. We highlight recommendations for the development and implementation of future experiments, discuss types of in situ measurements, experimental parameters, exposure scenarios and orbits, and identify knowledge gaps and how to advance scientific utilization of future space-exposure platforms that are either currently under development or in an advanced planning stage. In addition to the ISS, these platforms include CubeSats and SmallSats, as well as larger platforms such as the Lunar Orbital Gateway. We also provide an outlook for in situ experiments on the Moon and Mars, and welcome new possibilities to support the search for exoplanets and potential biosignatures within and beyond our solar system.
Acceso Abierto
The September 2002 Antarctic vortex major warming as observed by visible spectroscopy and ozone soundings
(Taylor & Francis Ltd, 2005-08) Yela González, M.; Parrondo Sempere, María Concepción; Gil Moulet, Manuel; Rodríguez, S.; Araujo, J.; Ochoa, H.; Deferrari, Guillermo Alejandro; Diaz, Susana Beatriz
The record of O3 total column and NO2 obtained by visible spectroscopy at Ushuaia (55° S), Marambio (64° S) and Belgrano (78° S) and vertical ozone profiles from the latter station provide insight into the unprecedented major warming observed above Antarctica in the last week of September 2002. From 18 September to 25 September the temperature increased 54°C at the isentropic level of 700 K. The temperature anomaly was observed down to the level of 300 K in which a well-defined tropopause was established. From comparison of the ozone profiles before and during the event, it can be seen that a fast increase in O3 took place basically above 500 K, but the layer where the ozone hole occurs was barely affected. Low potential vorticity values above Belgrano occurred only at levels above 500 K, confirming that the vortex split was confined to heights above the layer of the Antarctic spring depletion. The signature of poleward-transported air is clearly visible from the NO2 column departure from the envelope of the previous years in all three stations. NO2 columns larger than typical for ozone hole conditions by 400% were observed at Belgrano. Diurnal variations provide evidence of non-denitrified extra-vortex air.
Acceso Abierto
Chemical depletion of Arctic ozone in winter 1999/2000
(American Geophysical Union, 2002-09-20) Rex, Markus; Salawitch, R. J.; Harris, Neil R. P.; Gathen, Peter von der; Braathen, Geir O.; Schulz, Astrid; Deckelmann, H.; Chipperfield, M.; Sinnhuber, B. M.; Reimer, E.; Alfier, R.; Bevilacqua, R.; Hoppel, K.; Fromm, M.; Lumpe, J.; Küllmann, H.; Kleinböhl, A.; Bremer, H.; Von König, M.; Künzi, K.; Toohey, D.; Vömel, H.; Richard, E.; Aikin, K.; Jost, H.; Greenblatt, J. B.; Loewenstein, M.; Podolske, J. R.; Webster, Christopher R.; Flesch, Gregory J.; Scott, D. C.; Herman, R. L.; Elkins, J. W.; Ray, E. A.; Moore, F. L.; Hurst, D. F.; Romashkin, P.; Toon, G. C.; Sen, B.; Margitan, J. J.; Wennberg, P.; Neuber, R.; Allart, M.; Bojkov, B. R.; Claude, H.; Davies, Jonathan; Davies, W.; De Backer, H.; Dier, Horst; Dorokhov, Valery; Fast, H.; Kondo, Yutaka; Kyrö, E.; Litynska, Z.; Mikkelsen, I. S.; Molyneux, M. J.; Moran, E.; Nagai, T.; H. Nakane; Parrondo Sempere, María Concepción; Ravegnani, Fabrizio; Skrivánková, Pavla; Viatte, P.; Yushkov, Vladimir; European Commission (EC); National Aeronautics and Space Administration (NASA)
[1] During Arctic winters with a cold, stable stratospheric circulation, reactions on the surface of polar stratospheric clouds (PSCs) lead to elevated abundances of chlorine monoxide (ClO) that, in the presence of sunlight, destroy ozone. Here we show that PSCs were more widespread during the 1999/2000 Arctic winter than for any other Arctic winter in the past two decades. We have used three fundamentally different approaches to derive the degree of chemical ozone loss from ozonesonde, balloon, aircraft, and satellite instruments. We show that the ozone losses derived from these different instruments and approaches agree very well, resulting in a high level of confidence in the results. Chemical processes led to a 70% reduction of ozone for a region ∼1 km thick of the lower stratosphere, the largest degree of local loss ever reported for the Arctic. The Match analysis of ozonesonde data shows that the accumulated chemical loss of ozone inside the Arctic vortex totaled 117 ± 14 Dobson units (DU) by the end of winter. This loss, combined with dynamical redistribution of air parcels, resulted in a 88 ± 13 DU reduction in total column ozone compared to the amount that would have been present in the absence of any chemical loss. The chemical loss of ozone throughout the winter was nearly balanced by dynamical resupply of ozone to the vortex, resulting in a relatively constant value of total ozone of 340 ± 50 DU between early January and late March. This observation of nearly constant total ozone in the Arctic vortex is in contrast to the increase of total column ozone between January and March that is observed during most years.
Acceso Abierto
Arctic ozone loss in threshold conditions: Match observations in 1997/1998 and 1998/1999
(American Geophysical Union, 2001-04-01) Schulz, Astrid; Rex, Markus; Harris, Neil R. P.; Braathen, Geir O.; Reimer, E.; Alfier, R.; Kilbane Dawe, Iarla; Eckermann, Stephen; Allaart, Marc; Alpers, Matthias; Bojkov, B; Cisneros Sanchiz, Juan María; Claude, H.; Cuevas Agulló, Emilio; Davies, Jonathan; Backer, Hugo de; Dier, Horst; Dorokhov, Valery; Fast, Hans; Godin, Sophie; Johnson, B. J.; Kois, Bogumil; Kondo, Yutaka; Kosmidis, Evangelos; Kyrö, Esko; Litynska, Z.; Mikkelsen, I. S.; Molyneux, M. J.; Murphy, Gerry; Nagai, T.; Nakane, Hideaki; O'Connor, Fiona M.; Parrondo Sempere, María Concepción; Schmidlin, Frank J.; Skrivánková, Pavla; Varotsos, Costas; Vialle, C.; Viatte, P.; Yushkov, Vladimir; Zerefos, Christos S.; Gathen, Peter von der; European Commission (EC)
Chemical ozone loss rates inside the Arctic polar vortex were determined in early 1998 and early 1999 by using the Match technique based on coordinated ozonesonde measurements. These two winters provide the only opportunities in recent years to investigate chemical ozone loss in a warm Arctic vortex under threshold conditions, i.e., where the preconditions for chlorine activation, and hence ozone destruction, only occurred occasionally. In 1998, results were obtained in January and February between 410 and 520 K. The overall ozone loss was observed to be largely insignificant, with the exception of late February, when those air parcels exposed to temperatures below 195 K were affected by chemical ozone loss. In 1999, results are confined to the 475 K isentropic level, where no significant ozone loss was observed. Average temperatures were some 8°–10° higher than those in 1995, 1996, and 1997, when substantial chemical ozone loss occurred. The results underline the strong dependence of the chemical ozone loss on the stratospheric temperatures. This study shows that enhanced chlorine alone does not provide a sufficient condition for ozone loss. The evolution of stratospheric temperatures over the next decade will be the determining factor for the amount of wintertime chemical ozone loss in the Arctic stratosphere.
Acceso Abierto
Match observations in the Arctic winter 1996/97: High stratospheric ozone loss rates correlate with low temperatures deep inside the polar vortex
(American Geophysical Union, 2020-01-15) Schulz, Astrid; Rex, Markus; Steger, J.; Harris, Neil R. P.; Braathen, Geir O.; Reimer, E.; Alfier, R.; Beck, A.; Alpers, Matthias; Cisneros Sanchiz, Juan María; Claude, H.; De Backer, Hugo; Dier, Horst; Dorokhov, Valery; Fast, Hans; Godin, Sophie; Hansen, Georg; Kanzawa, Hiroshi; Kois, Bogumil; Kondo, Yutaka; Kosmidis, Evangelos; Kyrö, Esko; Litynska, Z.; Molyneux, M. J.; Murphy, Gerry; Nakane, Hideaki; Parrondo Sempere, María Concepción; Ravegnani, Fabrizio; Varotsos, Costas; Vialle, C.; Viatte, P.; Yushkov, Vladimir; Zerefos, Christos S.; Gathen, Peter von der
With the Match technique, which is based on the coordinated release of ozonesondes, chemical ozone loss rates in the Arctic stratospheric vortex in early 1997 have been quantified in a vertical region between 400 K and 550 K. Ozone destruction was observed from mid February to mid March in most of these levels, with maximum loss rates between 25 and 45ppbv/day. The vortex averaged loss rates and the accumulated vertically integrated ozone loss have been smaller than in the previous two winters, indicating that the record low ozone columns observed in spring 1997 were partly caused by dynamical effects. The observed ozone loss is inhomogeneous through the vortex with the highest loss rates located in the vortex centre, coinciding with the lowest temperatures. Here the loss rates per sunlit hour reached 6 ppbv/h, while the corresponding vortex averaged rates did not exceed 3.9 ppbv/h.
Acceso Abierto
Drying of the Martian mesosphere during aphelion induced by lower temperatures
(Springer Nature, 2024-11-20) Toledo, D.; Rannou, P.; Apéstigue, V.; Rodríguez Veloso, Raúl; Arruego, I.; Martínez, Germán M.; Tamppari, L. K.; Munguira, A.; Lorenz, Ralph; Stcherbinine, Aurélien; Montmessin, F.; Sánchez Lavega, Agustín; Patel, P.; Smith, Michael D.; Lemmon, M. T.; Vicente Retortillo, Álvaro; Newman, C. E.; Viúdez Moreiras, Daniel; Hueso, R.; Bertrand, T.; Pla García, J.; Yela González, M.; De la Torre Juárez, M.; Rodríguez Manfredi, J. A.; Apéstigue, Víctor; Ministerio de Ciencia e Innovación (MICINN); Jet Propulsion Laboratory (JPL); National Aeronautics and Space Administration (NASA); Gobierno Vasco; Agencia Estatal de Investigación (AEI); Unidad de Excelencia Científica María de Maeztu Instituto de Astrofísica de Cantabria, MDM-2017-0765
The formation of water ice clouds or hazes on Mars imposes substantial limitations on the vertical transport of water into the middle-upper atmosphere, impacting the planet’s hydrogen loss. Recent observations made by the Mars Environmental Dynamics Analyzer instrument onboard Mars 2020 Perseverance rover have shown a marked decline in water ice abundance within the mesosphere (above 35-40 km) when Mars is near its aphelion (near the northern summer solstice), notably occurring during solar longitudes (Ls) between Ls 70∘ and 80∘. Orbital observations around the same latitudes indicate that temperatures between ~ 30-40 km reach a minimum during the same period. Using cloud microphysics simulations, we demonstrate that this decrease in temperature effectively increases the amount of water cold-trapped at those altitudes, confining water ice condensation to lower altitudes. Similarly, the reinforcement of the cold trap induced by the lower temperatures results in significant reductions in the water vapor mixing ratio above 35–40 km, explaining the confinement of water vapor observed around aphelion from orbiters.
Acceso Abierto
Ozone Detector Based on Ultraviolet Observations on the Martian Surface
(Multidisciplinary Digital Publishing Institute, 2024-10-21) Viúdez Moreiras, Daniel; Saiz López, A.; Smith, Michael D.; Apéstigue, V.; Arruego, I.; García Menéndez, Elisa; Jiménez Martín, Juan José; Rodríguez Manfredi, J. A.; Toledo, D.; Wolff, Michael; Paz Zorzano, M.; Apéstigue, Víctor; Ministerio de Ciencia e Innovación (MICINN); Agencia Estatal de Investigación (AEI); Ministerio de Economía y Competitividad (MINECO)
Ozone plays a key role in both atmospheric chemistry and UV absorption in planetary atmospheres. On Mars, upper-tropospheric ozone has been widely characterized by space-based instruments. However, surface ozone remains poorly characterized, hindered by the limited sensitivity of orbiters to the lowest scale height of the atmosphere and challenges in delivering payloads to the surface of Mars, which have prevented, to date, the measurement of ozone from the surface of Mars. Systematic measurements from the Martian surface could advance our knowledge of the atmospheric chemistry and habitability potential of this planet. NASA’s Mars 2020 mission includes the first ozone detector deployed on the Martian surface, which is based on discrete photometric observations in the ultraviolet band, a simple technology that could obtain the first insights into total ozone abundance in preparation for more sophisticated measurement techniques. This paper describes the Mars 2020 ozone detector and its retrieval algorithm, including its performance under different sources of uncertainty and the potential application of the retrieval algorithm on other missions, such as NASA’s Mars Science Laboratory. Pre-landing simulations using the UVISMART radiative transfer model suggest that the retrieval is robust and that it can deal with common issues affecting surface operations in Martian missions, although the expected low ozone abundance and instrument uncertainties could challenge its characterization in tropical latitudes of the planet. Other space missions will potentially include sensors of similar technology.
Restringido
Magnetic Characterization of Permalloy Nanodome Surfaces on Flexible PEEK/TiO2 Vertical Nanotubes Composites
(IEEE, 2022-10-10) Martín Rubio, C.; Rivelles García, Alejandro; Schneider, Marc; Del Hoyo, J. C.; Privitera, V.; Worgull, M.; del Hoyo Gordillo, Juan Carlos
Poly-ether-ether-ketone (PEEK) composites present outstanding physical and chemical properties, including radiation tolerance and compatibility with vacuum and additive manufacturing processing. Applications of PEEK range from biomedical to aerospace. Controlled 3-D nanostructuring arises as a powerful approach to generate new phenomena suitable for technological applications. In this sense, we target to synthesize robust and shapeable magnetic nanocomposites (NCs) for sensing and electromagnetic shielding applications. For this aim, we synthesized and characterized Permalloy (Py, Ni80Fe20) nanostructured surfaces on PEEK/TiO2. These NCs were synthesized by scalable and high throughput compatible fabrication approaches: anodization (TiO2 nanotubes) and hot embossing (thermal nanoimprint). The resulting NCs are shapeable, stable below 300 °C, and vacuum compatible. Their surfaces compose TiO2 nanodomes filled by PEEK. Py layers (15 nm) were sputtered on NC and flat PEEK films. The characterization included SEM, AFM, ISO-2409 Adhesion Tests, hysteresis loops, and first-order reversal curves (FORCs). The results revealed that both types of films keep stable characteristics after bending cycles, and noticeable modifications of the magnetic global response and local interactions generated due to the 3-D nanostructure.
Acceso Abierto
A nocturnal atmospheric loss of CH2I2 in the remote marine boundary layer
(Kluwer Academic Publishers, 2015-10-05) Ouyang, Bin; Jones, Roderic L.; Carpenter, Lucy J.; Andrews, Stephen J.; Lidster, Richard T.; Saiz López, A.; Fernández Sánchez, Miguel; Blosss, William J.
Ocean emissions of inorganic and organic iodine compounds drive the biogeochemical cycle of iodine and produce reactive ozone-destroying iodine radicals that influence the oxidizing capacity of the atmosphere. Di-iodomethane (CH2I2) and chloro-iodomethane (CH2ICl) are the two most important organic iodine precursors in the marine boundary layer. Ship-borne measurements made during the TORERO (Tropical Ocean tRoposphere Exchange of Reactive halogens and Oxygenated VOC) field campaign in the east tropical Pacific Ocean in January/February 2012 revealed strong diurnal cycles of CH2I2 and CH2ICl in air and of CH2I2 in seawater. Both compounds are known to undergo rapid photolysis during the day, but models assume no night-time atmospheric losses. Surprisingly, the diurnal cycle of CH2I2 was lower in amplitude than that of CH2ICl, despite its faster photolysis rate. We speculate that night-time loss of CH2I2 occurs due to reaction with NO3 radicals. Indirect results from a laboratory study under ambient atmospheric boundary layer conditions indicate a k CH2I2+NO3 of ≤4 × 10−13 cm3 molecule−1 s−1; a previous kinetic study carried out at ≤100 Torr found k CH2I2+NO3 of 4 × 10−13 cm3 molecule−1 s−1. Using the 1-dimensional atmospheric THAMO model driven by sea-air fluxes calculated from the seawater and air measurements (averaging 1.8 +/− 0.8 nmol m−2 d−1 for CH2I2 and 3.7 +/− 0.8 nmol m−2 d−1 for CH2ICl), we show that the model overestimates night-time CH2I2 by >60 % but reaches good agreement with the measurements when the CH2I2 + NO3 reaction is included at 2–4 × 10−13 cm3 molecule−1 s−1. We conclude that the reaction has a significant effect on CH2I2 and helps reconcile observed and modeled concentrations. We recommend further direct measurements of this reaction under atmospheric conditions, including of product branching ratios.
Restringido
Greenhouse gases in the tall tower of El Arenosillo station in Southwestern Europe: First-year of measurements
(Elsevier, 2024-01-06) Adame, J. A.; Padilla, Rubén; Gutiérrez Álvarez, I.; Bogeat, José Antonio; López, Alfonso; Yela González, M.; Padilla, Rubén; Bogeat Sánchez-Piqueras, José Antonio
Carbon dioxide (CO2), methane (CH4) and carbon monoxide (CO) were measured at 10, 50 and 100 m in a tall tower located at El Arenosillo observatory (Southwestern Europe) from December 2021 to December 2022. Depending on the height, hourly averages varied between 418 ± 5 at 100 m and 422 ± 8 μmol mol−1 at 10 m for CO2, while CH4 varied between 1999 ± 30 nmol mol−1 at 100 m and 1986 ± 25 at 10 m and ∼ 102 ± 19 nmol mol−1 for CO. A monthly variation with a common maximum in January–February was obtained while the minimum was found in June for CH4 and CO, whereas the minimum for CO2 was in August. The seasonal daily patterns showed a maximum between 5:00 and 10:00 UTC while the minimum was observed at 15:00–18:00 UTC. The daily variations are controlled by atmospheric stability, photochemical activity and vegetation influence, among other factors. The CO2 gradient was strongly conditioned by the photosynthesis, plant and soil respiration and vertical mixing with peaks higher than 19 × 10−2 μmol mol−1 m−1 at ∼5:00 UTC in spring and autumn. The CH4 gradient, greater in winter and autumn (12–27 × 10−2 μmol mol−1 m−1) is affected by vertical stability, local emissions and photochemical activity while CO depicted small vertical gradients. A different behavior was found in the CO2 and CH4 gradients, for CO2 the 10–50 m gradient is higher than 50–100 m while CH4 was the opposite; which could reflect a lower CO2 surface layer than CH4. The observations at 100 m registered CO and CH4 peaks that were not recorded at 10 m, which could be associated with the arrival of a forest fire plume and potential CH4 fugitive emissions
Acceso Abierto
The sound of a Martian dust devil
(Nature, 2022-12-13) Murdoch, N.; Stott, A. E.; Gillier, M.; Hueso, R.; Lemmon, M. T.; Martínez, Germán M.; Apéstigue, V.; Toledo, D.; Lorenz, R. D.; Chide, B.; Munguira, A.; Sánchez Lavega, Agustín; Vicente Retortillo, Álvaro; Newman, C. E.; Maurice, S.; De la Torre Juárez, M.; Bertrand, T.; Banfield, D.; Navarro López, Sara; Marín, M.; Torres, J.; Gómez Elvira, J.; Jacob, Xavier; Cadu, A.; Sournac, A.; Rodríguez Manfredi, J. A.; Mimoun, D.; Apéstigue, Víctor; National Aeronautics and Space Administration (NASA); Centre National D'Etudes Spatiales (CNES); NASA Jet Propulsion Laboratory (JPL); Comunidad de Madrid; Gobierno Vasco; Agencia Estatal de Investigación (AEI); Los Alamos National Laboratory; Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Dust devils (convective vortices loaded with dust) are common at the surface of Mars, particularly at Jezero crater, the landing site of the Perseverance rover. They are indicators of atmospheric turbulence and are an important lifting mechanism for the Martian dust cycle. Improving our understanding of dust lifting and atmospheric transport is key for accurate simulation of the dust cycle and for the prediction of dust storms, in addition to being important for future space exploration as grain impacts are implicated in the degradation of hardware on the surface of Mars. Here we describe the sound of a Martian dust devil as recorded by the SuperCam instrument on the Perseverance rover. The dust devil encounter was also simultaneously imaged by the Perseverance rover’s Navigation Camera and observed by several sensors in the Mars Environmental Dynamics Analyzer instrument. Combining these unique multi-sensorial data with modelling, we show that the dust devil was around 25 m large, at least 118 m tall, and passed directly over the rover travelling at approximately 5 m s−1. Acoustic signals of grain impacts recorded during the vortex encounter provide quantitative information about the number density of particles in the vortex. The sound of a Martian dust devil was inaccessible until SuperCam microphone recordings. This chance dust devil encounter demonstrates the potential of acoustic data for resolving the rapid wind structure of the Martian atmosphere and for directly quantifying wind-blown grain fluxes on Mars.
Acceso Abierto
Diurnal and Seasonal Variations of Aerosol Optical Depth Observed by MEDA/TIRS at Jezero Crater, Mars
(Advancing Earth and Space Science (AGU), 2023-01-09) Smith, Michael D.; Martínez, Germán M.; Sebastián, E.; Lemmon, M. T.; Wolff, Michael; Apéstigue, V.; Arruego, I.; Toledo, D.; Viúdez Moreiras, Daniel; Rodríguez Manfredi, J. A.; De la Torre Juárez, M.; Apéstigue, Víctor; National Aeronautics and Space Administration (NASA); Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
The two upward-looking Thermal InfraRed Sensor (TIRS) channels from the Mars Environmental Dynamics Analyzer (MEDA) instrument suite on board the Perseverance rover enable the retrieval of total aerosol optical depth (dust plus water ice cloud) above the rover for all observations when TIRS is taken. Because TIRS observes at thermal infrared wavelengths, the retrievals are possible during both the day and night and thus, they provide an excellent way to monitor both the diurnal and seasonal variations of aerosols above Jezero Crater. A retrieval algorithm has been developed for this purpose and here, we describe that algorithm along with our results for the first 400 sols of the Perseverance mission covering nearly the entire aphelion season as well as a regional dust storm and the beginning of the perihelion season. We find systematic diurnal variations in aerosol optical depth that can be associated with dust and water ice clouds as well as a clear change from a cloud-filled aphelion season to a perihelion season where dust is the dominant aerosol. A comparison of retrieved optical depths between TIRS and the SkyCam camera that is also part of MEDA indicates evidence of possible diurnal variations in cloud height or particle size.
Acceso Abierto
A nocturnal atmospheric loss of CH2I2 in the remote marine boundary layer
(Springer Link, 2015-10-05) Carpenter, Lucy J.; Andrews, Stephen J.; Lidster, Richard T.; Saiz López, A.; Fernández Sánchez, Miguel; Blosss, William J.; Ouyang, Bin; Jones, Roderic L.; National Aeronautics and Space Administration (NASA)
Ocean emissions of inorganic and organic iodine compounds drive the biogeochemical cycle of iodine and produce reactive ozone-destroying iodine radicals that influence the oxidizing capacity of the atmosphere. Di-iodomethane (CH2I2) and chloro-iodomethane (CH2ICl) are the two most important organic iodine precursors in the marine boundary layer. Ship-borne measurements made during the TORERO (Tropical Ocean tRoposphere Exchange of Reactive halogens and Oxygenated VOC) field campaign in the east tropical Pacific Ocean in January/February 2012 revealed strong diurnal cycles of CH2I2 and CH2ICl in air and of CH2I2 in seawater. Both compounds are known to undergo rapid photolysis during the day, but models assume no night-time atmospheric losses. Surprisingly, the diurnal cycle of CH2I2 was lower in amplitude than that of CH2ICl, despite its faster photolysis rate. We speculate that night-time loss of CH2I2 occurs due to reaction with NO3 radicals. Indirect results from a laboratory study under ambient atmospheric boundary layer conditions indicate a k CH2I2+NO3 of ≤4 × 10−13 cm3 molecule−1 s−1; a previous kinetic study carried out at ≤100 Torr found k CH2I2+NO3 of 4 × 10−13 cm3 molecule−1 s−1. Using the 1-dimensional atmospheric THAMO model driven by sea-air fluxes calculated from the seawater and air measurements (averaging 1.8 +/− 0.8 nmol m−2 d−1 for CH2I2 and 3.7 +/− 0.8 nmol m−2 d−1 for CH2ICl), we show that the model overestimates night-time CH2I2 by >60 % but reaches good agreement with the measurements when the CH2I2 + NO3 reaction is included at 2–4 × 10−13 cm3 molecule−1 s−1. We conclude that the reaction has a significant effect on CH2I2 and helps reconcile observed and modeled concentrations. We recommend further direct measurements of this reaction under atmospheric conditions, including of product branching ratios.
Acceso Abierto
Using the Perseverance MEDA-RDS to identify and track dust devils and dust-lifting gust fronts
(Frontiers, 2023-10-11) Toledo, D.; Apéstigue, V.; Martínez Oter, J.; Franchi, Fulvio; Serrano, F.; Yela González, M.; De la Torre Juárez, M.; Rodríguez Manfredi, J. A.; Arruego, I.; Apéstigue, Víctor; European Commission (EC); Agencia Estatal de Investigación (AEI); Ministerio de Economía y Competitividad (MINECO)
In the framework of the Europlanet 2024 Research Infrastructure Transnational Access programme, a terrestrial field campaign was conducted from 29 September to 6 October 2021 in Makgadikgadi Salt Pans (Botswana). The main goal of the campaign was to study in situ the impact of the dust devils (DDs) on the observations made by the radiometer Radiation and Dust Sensor (RDS), which is part of the Mars Environmental Dynamics Analyzer instrument, on board NASA’s Mars 2020 Perseverance rover. Several DDs and dust lifting events caused by non-vortex wind gusts were detected using the RDS, and the different impacts of these events were analyzed in the observations. DD diameter, advection velocity, and trajectory were derived from the RDS observations, and then, panoramic videos of such events were used to validate these results. The instrument signal variations produced by dust lifting (by vortices or wind gusts) in Makgadikgadi Pans are similar to those observed on Mars with the RDS, showing the potential of this location as a Martian DD analog.
Acceso Abierto
Dust Lifting Through Surface Albedo Changes at Jezero Crater, Mars
(Advancing Earth and Space Science (AGU), 2023-03-22) Vicente Retortillo, Álvaro; Martínez, Germán M.; Lemmon, M. T.; Hueso, R.; Johnson, J. R.; Sullivan, Robert; Newman, C. E.; Sebastián, E.; Toledo, D.; Apéstigue, V.; Arruego, I.; Munguira, A.; Sánchez Lavega, Agustín; Murdoch, N.; Gillier, M.; Stott, A.; Mora Sotomayor, L.; Bertrand, T.; Tamppari, L. K.; De la Torre Juárez, M.; Rodríguez Manfredi, J. A.; Apéstigue, Víctor; Agencia Estatal de Investigación (AEI); National Aeronautics and Space Administration (NASA); Comunidad de Madrid; Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
We identify temporal variations in surface albedo at Jezero crater using first-of-their-kind high-cadence in-situ measurements of reflected shortwave radiation during the first 350 sols of the Mars 2020 mission. Simultaneous Mars Environmental Dynamics Analyzer (MEDA) measurements of pressure, radiative fluxes, winds, and sky brightness indicate that these albedo changes are caused by dust devils under typical conditions and by a dust storm at Ls ∼ 155°. The 17% decrease in albedo caused by the dust storm is one order of magnitude larger than the most apparent changes caused during quiescent periods by dust devils. Spectral reflectance measurements from Mastcam-Z images before and after the storm indicate that the decrease in albedo is mainly caused by dust removal. The occurrence of albedo changes is affected by the intensity and proximity of the convective vortex, and the availability and mobility of small particles at the surface. The probability of observing an albedo change increases with the magnitude of the pressure drop (ΔP): changes were detected in 3.5%, 43%, and 100% of the dust devils with ΔP < 2.5 Pa, ΔP > 2.5 Pa and ΔP > 4.5 Pa, respectively. Albedo changes were associated with peak wind speeds above 15 m·s−1. We discuss dust removal estimates, the observed surface temperature changes coincident with albedo changes, and implications for solar-powered missions. These results show synergies between multiple instruments (MEDA, Mastcam-Z, Navcam, and the Supercam microphone) that improve our understanding of aeolian processes on Mars.
Acceso Abierto
The Uranus Multi-Experiment Radiometer for Haze and Clouds Characterization
(Springer Link, 2024-01-09) Apéstigue, V.; Toledo, D.; Irwin, P. G. J.; Rannou, P.; Gonzalo Melchor, Alejandro; Martínez Oter, J.; Ceballos Cáceres, J.; Azcue, J.; Jiménez Martín, Juan José; Sebastián, E.; Yela González, M.; Sorribas, M.; De Mingo, J. R.; Martín Ortega, A.; Belenguer Dávila, T.; Álvarez, Maite; Vázquez García de la Vega, D.; Espejo, S.; Arruego, I.; Apéstigue, Víctor; Gonzalo Melchor, Alejandro; de Mingo Martín, José Ramón; Martín-Ortega, Alberto
The aerosols (clouds and hazes) on Uranus are one of the main elements for understanding the thermal structure and dynamics of its atmosphere. Aerosol particles absorb and scatter the solar radiation, directly affecting the energy balance that drives the atmospheric dynamics of the planet. In this sense, aerosol information such as the vertical distribution or optical properties is essential for characterizing the interactions between sunlight and aerosol particles at each altitude in the atmosphere and for understanding the energy balance of the planet’s atmosphere. Moreover, the distribution of aerosols in the atmosphere provides key information on the global circulation of the planet (e.g., regions of upwelling or subsidence). To address this challenge, we propose the Uranus Multi-experiment Radiometer (UMR), a lightweight instrument designed to characterize the aerosols in Uranus’ atmosphere as part of the upcoming Uranus Flagship mission’s descending probe payload. The scientific goals of UMR are: (1) to study the variation of the solar radiation in the ultra-violet (UV) with altitude and characterize the energy deposition in the atmosphere; (2) to study the vertical distribution of the hazes and clouds and characterize their scattering and optical properties; (3) to investigate the heating rates of the atmosphere by directly measuring the upward and downward fluxes; and (4) to study the cloud vertical distribution and composition at pressures where sunlight is practically negligible (p > 4-5 bars). The instrument includes a set of photodetectors, field-of-view masks, a light infrared lamp, and interference filters. It draws on the heritage of previous instruments developed at the Instituto Nacional de Técnica Aeroespacial (INTA) that participated in the exploration of Mars, where similar technology has demonstrated its endurance in extreme environments while utilizing limited resources regarding power consumption, mass and volume footprints, and data budget. The radiometer’s design and characteristics make it a valuable complementary payload for studying Uranus’ atmosphere with a high scientific return.
Acceso Abierto
Asymmetrical magnetization processes induced by compositional gradients in ferromagnetic nanowires
(Elsevier, 2024-01-16) Fernández González, Claudia; Berja, Alba; Álvaro Gómez, Laura; Martín Rubio, C.; Mascaraque, Arantzazu; Aballe, Lucía; Sanz, Ruy; Pérez, L.; Ruiz Gómez, Sandra; Centros de Excelencia Severo Ochoa, INSTITUTO MADRILEÑO DE ESTUDIOS AVANZADOS EN NANOCIENCIA, SEV-2016-0686
Electrodeposited nanowires are an excellent scenario to study and control magnetic domain wall motion in nanostructures. In particular, the introduction of local changes in composition during the growth procedure has been proven to be very efficient for controlling the magnetization dynamics. In this work, we show the possibility of introducing compositional gradients in FeNi electrodeposited nanowires by gradually changing the Fe/Ni ratio along their axis. These compositional gradients produce an asymmetrical landscape for domain wall motion which is reflected in asymmetrical magnetization processes under an applied magnetic field. By studying nanowires with different compositional gradients we were able to correlate composition and magnetic asymmetry. Our results pave the way towards full control of the movement of domain walls along the nanowires.

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