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1.
Space Sci Rev ; 217(1): 24, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33612866

RESUMO

Mastcam-Z is a multispectral, stereoscopic imaging investigation on the Mars 2020 mission's Perseverance rover. Mastcam-Z consists of a pair of focusable, 4:1 zoomable cameras that provide broadband red/green/blue and narrowband 400-1000 nm color imaging with fields of view from 25.6° × 19.2° (26 mm focal length at 283 µrad/pixel) to 6.2° × 4.6° (110 mm focal length at 67.4 µrad/pixel). The cameras can resolve (≥ 5 pixels) ∼0.7 mm features at 2 m and ∼3.3 cm features at 100 m distance. Mastcam-Z shares significant heritage with the Mastcam instruments on the Mars Science Laboratory Curiosity rover. Each Mastcam-Z camera consists of zoom, focus, and filter wheel mechanisms and a 1648 × 1214 pixel charge-coupled device detector and electronics. The two Mastcam-Z cameras are mounted with a 24.4 cm stereo baseline and 2.3° total toe-in on a camera plate ∼2 m above the surface on the rover's Remote Sensing Mast, which provides azimuth and elevation actuation. A separate digital electronics assembly inside the rover provides power, data processing and storage, and the interface to the rover computer. Primary and secondary Mastcam-Z calibration targets mounted on the rover top deck enable tactical reflectance calibration. Mastcam-Z multispectral, stereo, and panoramic images will be used to provide detailed morphology, topography, and geologic context along the rover's traverse; constrain mineralogic, photometric, and physical properties of surface materials; monitor and characterize atmospheric and astronomical phenomena; and document the rover's sample extraction and caching locations. Mastcam-Z images will also provide key engineering information to support sample selection and other rover driving and tool/instrument operations decisions.

2.
J Geophys Res Planets ; 125(12): e2020JE006527, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33520561

RESUMO

This paper provides an overview of the Curiosity rover's exploration at Vera Rubin ridge (VRR) and summarizes the science results. VRR is a distinct geomorphic feature on lower Aeolis Mons (informally known as Mount Sharp) that was identified in orbital data based on its distinct texture, topographic expression, and association with a hematite spectral signature. Curiosity conducted extensive remote sensing observations, acquired data on dozens of contact science targets, and drilled three outcrop samples from the ridge, as well as one outcrop sample immediately below the ridge. Our observations indicate that strata composing VRR were deposited in a predominantly lacustrine setting and are part of the Murray formation. The rocks within the ridge are chemically in family with underlying Murray formation strata. Red hematite is dispersed throughout much of the VRR bedrock, and this is the source of the orbital spectral detection. Gray hematite is also present in isolated, gray-colored patches concentrated toward the upper elevations of VRR, and these gray patches also contain small, dark Fe-rich nodules. We propose that VRR formed when diagenetic event(s) preferentially hardened rocks, which were subsequently eroded into a ridge by wind. Diagenesis also led to enhanced crystallization and/or cementation that deepened the ferric-related spectral absorptions on the ridge, which helped make them readily distinguishable from orbit. Results add to existing evidence of protracted aqueous environments at Gale crater and give new insight into how diagenesis shaped Mars' rock record.

3.
J Geophys Res Planets ; 122(12): 2510-2543, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29497589

RESUMO

The Mars Science Laboratory Curiosity rover performed coordinated measurements to examine the textures and compositions of aeolian sands in the active Bagnold dune field. The Bagnold sands are rounded to subrounded, very fine to medium sized (~45-500 µm) with ≥6 distinct grain colors. In contrast to sands examined by Curiosity in a dust-covered, inactive bedform called Rocknest and soils at other landing sites, Bagnold sands are darker, less red, better sorted, have fewer silt-sized or smaller grains, and show no evidence for cohesion. Nevertheless, Bagnold mineralogy and Rocknest mineralogy are similar with plagioclase, olivine, and pyroxenes in similar proportions comprising >90% of crystalline phases, along with a substantial amorphous component (35% ± 15%). Yet Bagnold and Rocknest bulk chemistry differ. Bagnold sands are Si enriched relative to other soils at Gale crater, and H2O, S, and Cl are lower relative to all previously measured Martian soils and most Gale crater rocks. Mg, Ni, Fe, and Mn are enriched in the coarse-sieved fraction of Bagnold sands, corroborated by visible/near-infrared spectra that suggest enrichment of olivine. Collectively, patterns in major element chemistry and volatile release data indicate two distinctive volatile reservoirs in Martian soils: (1) amorphous components in the sand-sized fraction (represented by Bagnold) that are Si-enriched, hydroxylated alteration products and/or H2O- or OH-bearing impact or volcanic glasses and (2) amorphous components in the fine fraction (<40 µm; represented by Rocknest and other bright soils) that are Fe, S, and Cl enriched with low Si and adsorbed and structural H2O.

4.
Science ; 343(6169): 1242777, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24324272

RESUMO

The Curiosity rover discovered fine-grained sedimentary rocks, which are inferred to represent an ancient lake and preserve evidence of an environment that would have been suited to support a martian biosphere founded on chemolithoautotrophy. This aqueous environment was characterized by neutral pH, low salinity, and variable redox states of both iron and sulfur species. Carbon, hydrogen, oxygen, sulfur, nitrogen, and phosphorus were measured directly as key biogenic elements; by inference, phosphorus is assumed to have been available. The environment probably had a minimum duration of hundreds to tens of thousands of years. These results highlight the biological viability of fluvial-lacustrine environments in the post-Noachian history of Mars.


Assuntos
Exobiologia , Meio Ambiente Extraterreno , Marte , Água , Baías , Carbono/análise , Sedimentos Geológicos/análise , Sedimentos Geológicos/classificação , Hidrogênio/análise , Concentração de Íons de Hidrogênio , Ferro/análise , Ferro/química , Nitrogênio/análise , Oxirredução , Oxigênio/análise , Fósforo/análise , Salinidade , Enxofre/análise , Enxofre/química
6.
Hospitals ; 54(8): 67-9, 1980 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-7358377

RESUMO

Decoration and design in pediatric units should relate to patients' developmental states, cognitive skills, and perceptions of reality rather than relying on cuteness and whimsy.


Assuntos
Arte , Criança Hospitalizada/psicologia , Arquitetura de Instituições de Saúde , Instalações de Saúde , Ambiente de Instituições de Saúde , Decoração de Interiores e Mobiliário , Adaptação Psicológica , Arteterapia , Criança , Pré-Escolar , Unidades Hospitalares , Humanos , Pais , Estados Unidos
7.
Paediatrician ; 9(3-4): 220-3, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7208073

RESUMO

This study indicates that despite a growing concern for the psychosocial needs of pediatric patients, most 'living-in' programs do not optimize parental presence. The survey points to a need for continued education for professionals, for the general public, and for parents about to admit their children regarding the psychological and developmental needs of hospitalized.


Assuntos
Unidades Hospitalares , Relações Pais-Filho , Pediatria , Adolescente , Criança , Desenvolvimento Infantil , Humanos , Lactente , Pais/psicologia , Relações entre Irmãos , Meio Social , Estresse Psicológico/terapia
8.
Am J Public Health ; 68(9): 847-50, 1978 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-686210

RESUMO

A nation-wide survey of Parent-Inclusive Pediatric Units identified innovations and restrictions in policies and practices. Questionnaires mailed to Directors of Nursing Service at 84 general hospitals which encourage parental "living-in" indicated that parents are provided with a place to sleep but infrequently are offered additional facilities, services, and guidance necessary to optimize their presence on the Parent-Inclusive Pediatric Unit. Restrictions on parents remaining with their children are common during highly stressful procedures. Results indicate a gap between research on the importance of parental presence and current hospital practice.


Assuntos
Unidades Hospitalares/organização & administração , Pais , Pediatria , Criança Hospitalizada , Pré-Escolar , Hospitais Gerais , Humanos , Lactente , Estados Unidos
14.
Pediatr Ann ; 1(3): 44-62, 1972 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24847821
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