Examinando por Autor "Herkenhoff, K. E."

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Acceso Abierto
Radiometric Calibration Targets for the Mastcam-Z Camera on the Mars 2020 Rover Mission
(Springer Link, 2020-12-03) Kinch, K. M.; Madsen, M. B.; Bell, J. F.; Maki, Justin N.; Bailey, P.; Hayes, A. G.; Jensen, O. B.; Merusi, M.; Bernt, M. H.; Sorensen, A. N.; Hilverda, M.; Cloutis, E.; Applin, D.; Mateo Martí, Eva; Manrique, J. A.; López Reyes, G.; Bello Arufe, A.; Ehlmann, B. L.; Buz, J.; Pommerol, A.; Thomas, N.; Affolter, L.; Herkenhoff, K. E.; Johnson, J. R.; Rice, M.; Corlies, P.; Tate, C.; Caplinger, M. A.; Jensen, E.; Kubacki, T.; Cisneros, E.; Paris, K.; Winhold, A.; European Research Council (ERC); Kinch, K. [0000-0002-4629-8880]; López Reyes, G. [0000-0003-1005-1760]; Manrique, J. A. [0000-0002-2053-2819]; Affolter, L. [0000-0002-2869-8522]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
The Mastcam-Z Camera is a stereoscopic, multispectral camera with zoom capability on NASA’s Mars-2020 Perseverance rover. The Mastcam-Z relies on a set of two deck-mounted radiometric calibration targets to validate camera performance and to provide an instantaneous estimate of local irradiance and allow conversion of image data to units of reflectance (R∗ or I/F) on a tactical timescale. Here, we describe the heritage, design, and optical characterization of these targets and discuss their use during rover operations. The Mastcam-Z primary calibration target inherits features of camera calibration targets on the Mars Exploration Rovers, Phoenix and Mars Science Laboratory missions. This target will be regularly imaged during flight to accompany multispectral observations of the martian surface. The primary target consists of a gold-plated aluminum base, eight strong hollow-cylinder Sm2Co17 alloy permanent magnets mounted in the base, eight ceramic color and grayscale patches mounted over the magnets, four concentric, ceramic grayscale rings and a central aluminum shadow post (gnomon) painted with an IR-black paint. The magnets are expected to keep the central area of each patch relatively free of Martian aeolian dust. The Mastcam-Z secondary calibration target is a simple angled aluminum shelf carrying seven vertically mounted ceramic color and grayscale chips and seven identical, but horizontally mounted ceramic chips. The secondary target is intended to augment and validate the calibration-related information derived from the primary target. The Mastcam-Z radiometric calibration targets are critically important to achieving Mastcam-Z science objectives for spectroscopy and photometric properties.
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, Á.; Martínez, G. M.; Toledo, D.; Sullivan, R.; Herkenhoff, K. E.; De la Torre Juárez, M.; Richardson, M. I.; Stott, A. E.; Murdoch, N.; Sánchez Lavega, A.; Wolff, M. J.; Arruego, I.; Sebastián, E.; Navarro, Sara; Gómez Elvira, J.; Tamppari, L. K.; Smith, M. D.; Lepinette, A.; Viúdez Moreiras, Daniel; Harri, Ari-Matti; Genzer, M.; Hieta, M.; Lorenz, R. D.; Conrad, Pamela G.; Gómez, F.; Mcconnochie, T. 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, 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, S. D.; Apéstigue, Víctor; 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.