Examinando por Autor "Sullivan, Robert"

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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, Víctor; Arruego, Ignacio; 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.; 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
Dust, Sand, and Winds Within an Active Martian Storm in Jezero Crater
(AGU Advancing Earth and Space Science, 2022-11-16) Lemmon, M. T.; Smith, Michael D.; Viúdez Moreiras, Daniel; De la Torre Juárez, M.; Vicente Retortillo, Álvaro; Munguira, A.; Sánchez Lavega, Agustín; Hueso, R.; Martínez, Germán M.; Chide, B.; Sullivan, Robert; Toledo, D.; Tamppari, L. K.; Bertrand, T.; Bell, J. F.; Newman, C. E.; Baker, M.; Banfield, D.; Rodríguez Manfredi, J. A.; Maki, Justin N.; Apéstigue, Víctor; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Ciencia e Innovación (MICINN); Ministerio de Economía y Competitividad (MINECO); NASA Jet Propulsion Laboratory (JPL); Arizona State University (ASU); European Research Council (ERC); Agencia Estatal de Investigación (AEI); Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Rovers and landers on Mars have experienced local, regional, and planetary-scale dust storms. However, in situ documentation of active lifting within storms has remained elusive. Over 5–11 January 2022 (LS 153°–156°), a dust storm passed over the Perseverance rover site. Peak visible optical depth was ∼2, and visibility across the crater was briefly reduced. Pressure amplitudes and temperatures responded to the storm. Winds up to 20 m s−1 rotated around the site before the wind sensor was damaged. The rover imaged 21 dust-lifting events—gusts and dust devils—in one 25-min period, and at least three events mobilized sediment near the rover. Rover tracks and drill cuttings were extensively modified, and debris was moved onto the rover deck. Migration of small ripples was seen, but there was no large-scale change in undisturbed areas. This work presents an overview of observations and initial results from the study of the storm.
Acceso Abierto
Multi-model Meteorological and Aeolian Predictions for Mars 2020 and the Jezero Crater Region
(Springer Link, 2021-02-08) Newman, C. E.; Torres Juárez, M.; Pla García, J.; Wilson, R. J.; Lewis, S. R.; Neary, L.; Kahre, M. A.; Forget, F.; Spiga, A.; Richardson, M. L. A.; Daerden, F.; Bertrand, T.; Viúdez Moreiras, Daniel; Sullivan, Robert; Sánchez Lavega, Agustín; Chide, B.; Rodríguez Manfredi, J. A.; National Aeronautics and Space Administration (NASA); European Space Agency (ESA); Centre National D'Etudes Spatiales (CNES); Sánchez Lavega, Á. [0000-0001-7234-7634]; Lewis, S. [0000-0001-7237-6494]
Nine simulations are used to predict the meteorology and aeolian activity of the Mars 2020 landing site region. Predicted seasonal variations of pressure and surface and atmospheric temperature generally agree. Minimum and maximum pressure is predicted at Ls∼145∘ and 250∘, respectively. Maximum and minimum surface and atmospheric temperature are predicted at Ls∼180∘ and 270∘, respectively; i.e., are warmest at northern fall equinox not summer solstice. Daily pressure cycles vary more between simulations, possibly due to differences in atmospheric dust distributions. Jezero crater sits inside and close to the NW rim of the huge Isidis basin, whose daytime upslope (∼east-southeasterly) and nighttime downslope (∼northwesterly) winds are predicted to dominate except around summer solstice, when the global circulation produces more southerly wind directions. Wind predictions vary hugely, with annual maximum speeds varying from 11 to 19 ms−1 and daily mean wind speeds peaking in the first half of summer for most simulations but in the second half of the year for two. Most simulations predict net annual sand transport toward the WNW, which is generally consistent with aeolian observations, and peak sand fluxes in the first half of summer, with the weakest fluxes around winter solstice due to opposition between the global circulation and daytime upslope winds. However, one simulation predicts transport toward the NW, while another predicts fluxes peaking later and transport toward the WSW. Vortex activity is predicted to peak in summer and dip around winter solstice, and to be greater than at InSight and much greater than in Gale crater.
Acceso Abierto
The diverse meteorology of Jezero crater over the first 250 sols of Perseverance on Mars
(Nature Publishing Group, 2023-01-09) Rodríguez Manfredi, J. A.; De la Torre Juárez, M.; Sánchez Lavega, Agustín; Hueso, R.; Martínez, Germán M.; Lemmon, M. T.; Newman, C. E.; Munguira, A.; Hieta, M.; Tamppari, L. K.; Polkko, J.; Toledo, D.; Sebastian, D.; Smith, Michael D.; Jaakonaho, I.; Genzer, María; Vicente Retortillo, Álvaro; Viúdez Moreiras, Daniel; Ramos, Miguel; Saiz López, A.; Lepinette Malvitte, A.; Wolff, Michael; Sullivan, R. J.; Gómez Elvira, J.; Apéstigue, Víctor; Conrad, P.; Del Río Gaztelurrutia, T.; Murdoch, N.; Arruego, Ignacio; Banfield, D.; Boland, J.; Brown, Adrian Jon; Ceballos Cáceres, J.; Domínguez Pumar, M.; Espejo, S.; Fairén, A.; Ferrándiz Guibelalde, Ricardo; Fischer, E.; García Villadangos, M.; Giménez Torregrosa, S.; Gómez Gómez, F.; Guzewich, Scott; Harri, Ari-Matti; Jiménez Martín, Juan José; Jiménez, V.; Makinen, Terhi; Marín Jiménez, M.; Martín Rubio, C.; Martín Soler, J.; Molina, A.; Mora Sotomayor, L.; Navarro López, Sara; Peinado, V.; Pérez Grande, I.; Pla García, J.; Postigo, M.; Prieto-Ballesteros, Olga; Rafkin, Scot C. R.; Richardson, M. I.; Romeral, J.; Romero Guzmán, Catalina; Savijärvi, H.; Schofield, J. T.; Torres, J.; Urquí, R.; Zurita, S.; NASA Jet Propulsion Laboratory (JPL); National Aeronautics and Space Administration (NASA); Instituto Nacional de Técnica Aeroespacial (INTA); European Commission (EC); Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); California Institute of Technology (CIT); Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
NASA’s Perseverance rover’s Mars Environmental Dynamics Analyzer is collecting data at Jezero crater, characterizing the physical processes in the lowest layer of the Martian atmosphere. Here we present measurements from the instrument’s first 250 sols of operation, revealing a spatially and temporally variable meteorology at Jezero. We find that temperature measurements at four heights capture the response of the atmospheric surface layer to multiple phenomena. We observe the transition from a stable night-time thermal inversion to a daytime, highly turbulent convective regime, with large vertical thermal gradients. Measurement of multiple daily optical depths suggests aerosol concentrations are higher in the morning than in the afternoon. Measured wind patterns are driven mainly by local topography, with a small contribution from regional winds. Daily and seasonal variability of relative humidity shows a complex hydrologic cycle. These observations suggest that changes in some local surface properties, such as surface albedo and thermal inertia, play an influential role. On a larger scale, surface pressure measurements show typical signatures of gravity waves and baroclinic eddies in a part of the seasonal cycle previously characterized as low wave activity. These observations, both com
Acceso Abierto
The dynamic atmospheric and aeolian environment of Jezero crater, Mars
(Science Publishin Group, 2022-05-25) Newman, C. E.; Hueso, R.; Lemmon, M. T.; Munguira, A.; Vicente Retortillo, Álvaro; Apéstigue, Víctor; Martínez, Germán M.; Toledo, D.; Sullivan, Robert; Herkenhoff, K. E.; De la Torre Juárez, M.; Richardson, M. I.; Stott, A.; Murdoch, N.; Sánchez Lavega, Agustín; Wolff, Michael; Arruego, I.; Sebastián, E.; Navarro López, Sara; Gómez Elvira, J.; Tamppari, L. K.; Smith, Michael D.; Lepinette Malvitte, A.; Viúdez Moreiras, Daniel; Harri, Ari-Matti; Genzer, María; Hieta, M.; Lorenz, R. D.; Conrad, Pamela G.; Gómez, Felipe; McConnochie, Tim H.; Mimoun, D.; Tate, C.; Bertrand, T.; Belli, J. F.; Maki, Justin N.; Rodríguez Manfredi, J. A.; Wiens, R. C.; Chide, B.; Maurice, S.; Zorzano, María-Paz; Mora Sotomayor, L.; Baker, M. M.; Banfield, D.; Pla García, J.; Beyssac, O.; Brown, Adrian Jon; Clark, B.; Montmessin, F.; Fischer, E.; Patel, P.; Del Río Gaztelurrutia, T.; Fouchet, T.; Francis, R.; Guzewich, Scott; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Ciencia e Innovación (MICINN); Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); Gobierno Vasco; National Aeronautics and Space Administration (NASA); Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Despite the importance of sand and dust to Mars geomorphology, weather, and exploration, the processes that move sand and that raise dust to maintain Mars’ ubiquitous dust haze and to produce dust storms have not been well quantified in situ, with missions lacking either the necessary sensors or a sufficiently active aeolian environment. Perseverance rover’s novel environmental sensors and Jezero crater’s dusty environment remedy this. In Perseverance’s first 216 sols, four convective vortices raised dust locally, while, on average, four passed the rover daily, over 25% of which were significantly dusty (“dust devils”). More rarely, dust lifting by nonvortex wind gusts was produced by daytime convection cells advected over the crater by strong regional daytime upslope winds, which also control aeolian surface features. One such event covered 10 times more area than the largest dust devil, suggesting that dust devils and wind gusts could raise equal amounts of dust under nonstorm conditions.
Acceso Abierto
The Mars Environmental Dynamics Analyzer, MEDA. A Suite of Environmental Sensors for the Mars 2020 Mission
(Springer Link, 2021-04-13) Rodríguez Manfredi, J. A.; De la Torre Juárez, M.; Alonso, A.; Apéstigue, Víctor; Arruego, Ignacio; Atienza, T.; Banfield, D.; Boland, J.; Carrera, M. A.; Castañer, L.; Ceballos Cáceres, J.; Chen Chen, H.; Cobos, A.; Conrad, Pamela G.; Cordoba, E.; Del Río Gaztelurrutia, T.; Vicente Retortillo, Álvaro; Domínguez Pumar, M.; Espejo, S.; Fairén, Alberto G.; Fernández Palma, A.; Ferrándiz, Ricardo; Ferri, F.; Fischer, E.; García Manchado, A.; García Villadangos, M.; Genzer, María; Giménez, Á.; Gómez Elvira, J.; Gómez, Felipe; Guzewich, Scott; Harri, Ari-Matti; Hernández, C. D.; Hieta, M.; Hueso, R.; Jaakonaho, I.; Jiménez Martín, Juan José; Jiménez, V.; Larman, A.; Leiter, R.; Lepinette Malvitte, A.; Lemmon, M. T.; López, G.; Madsen, Soren N.; Mäkinen, T.; Marín Jiménez, M.; Martín Soler, J.; Martínez, Germán M.; Molina, A.; Mora Sotomayor, L.; Moreno Álvarez, J. F.; Navarro López, Sara; Newman, C. E.; Ortega, Cristina; Parrondo, María Concepción; Peinado, V.; Peña, A.; Pérez Grande, I.; Pérez Hoyos, S.; Pla García, J.; Polkko, J.; Postigo, M.; Prieto-Ballesteros, Olga; Rafkin, Scot C. R.; Ramos, Miguel; Richardson, M. I.; Romeral, J.; Romero Guzmán, Catalina; Runyon, Kirby; Saiz López, A.; Sánchez Lavega, Agustín; Sard, I.; Schofield, J. T.; Sebastián, E.; Smith, Michael D.; Sullivan, Robert; Tamppari, L. K.; Thompson, A. D.; Toledo, D.; Torrero, F.; Torres, J.; Urquí, R.; Velasco, T.; Viúdez Moreiras, Daniel; Zurita, S.; Agencia Estatal de Investigación (AEI); European Research Council (ERC); Gobierno Vasco; Rodríguez Manfredi, J. A. [0000-0003-0461-9815]; Saiz López, A. [0000-0002-0060-1581]; Chen, H. [0000-0001-9662-0308]; Pérez Hoyos, S. [0000-0002-2587-4682]
NASA’s Mars 2020 (M2020) rover mission includes a suite of sensors to monitor current environmental conditions near the surface of Mars and to constrain bulk aerosol properties from changes in atmospheric radiation at the surface. The Mars Environmental Dynamics Analyzer (MEDA) consists of a set of meteorological sensors including wind sensor, a barometer, a relative humidity sensor, a set of 5 thermocouples to measure atmospheric temperature at ∼1.5 m and ∼0.5 m above the surface, a set of thermopiles to characterize the thermal IR brightness temperatures of the surface and the lower atmosphere. MEDA adds a radiation and dust sensor to monitor the optical atmospheric properties that can be used to infer bulk aerosol physical properties such as particle size distribution, non-sphericity, and concentration. The MEDA package and its scientific purpose are described in this document as well as how it responded to the calibration tests and how it helps prepare for the human exploration of Mars. A comparison is also presented to previous environmental monitoring payloads landed on Mars on the Viking, Pathfinder, Phoenix, MSL, and InSight spacecraft.