5 research outputs found
A Pre-Landing Assessment of Regolith Properties at the InSight Landing Site
This article discusses relevant physical properties of the regolith at the Mars InSight landing site as understood prior to landing of the spacecraft. InSight will land in the northern lowland plains of Mars, close to the equator, where the regolith is estimated to be ≥3--5 m thick. These investigations of physical properties have relied on data collected from Mars orbital measurements, previously collected lander and rover data, results of studies of data and samples from Apollo lunar missions, laboratory measurements on regolith simulants, and theoretical studies. The investigations include changes in properties with depth and temperature. Mechanical properties investigated include density, grain-size distribution, cohesion, and angle of internal friction. Thermophysical properties include thermal inertia, surface emissivity and albedo, thermal conductivity and diffusivity, and specific heat. Regolith elastic properties not only include parameters that control seismic wave velocities in the immediate vicinity of the Insight lander but also coupling of the lander and other potential noise sources to the InSight broadband seismometer. The related properties include Poisson’s ratio, P- and S-wave velocities, Young’s modulus, and seismic attenuation. Finally, mass diffusivity was investigated to estimate gas movements in the regolith driven by atmospheric pressure changes. Physical properties presented here are all to some degree speculative. However, they form a basis for interpretation of the early data to be returned from the InSight mission.Additional co-authors: Nick Teanby and Sharon Keda
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NACA Advanced Restricted Reports
Report presenting an investigation that was conducted to determine the effect of carburetor dry-air temperature on the cooling characteristics of a typical full-scale air-cooled engine cylinder mounted on a single-cylinder crankcase
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(Des)ubicación: La Lucha por la Vivienda y la Comunidad Después de Echo Park Lake
Elaborado por el Colectivo de Investigación Después de Echo Park Lake, esta monografÃa analiza desplazamiento encabezado por el estado. Con un enfoque centrado en el desalojo violenta de la comunidad sin vivienda en Echo Park Lake, un parque publico en un barrio gentrificando de la ciudad cerca del centro, eso llama la atencion sobre cómo reclamos polÃticos de ubicaciónes de viviendas legitiman desubicación pero rara vez resulta en soluciones de la vivienda. A través de investigación etnográfica además de análisis de datos de la gestión de personas sin viviendas, eso expone la artimaña de la vivienda y llama la atención sobre un condición de dezplazabilidad definitiva por los pobres de la ciudad. Un hallazgo clave de la monografÃa es que en un tiempo de recursos de vivienda ampliados suscrito por fondos federales de emergencia y ayuda económica, tiene un inversión perversa de fondos públicos para la criminalización de pobreza y contención carcelaria de los personas sin viviendas. En marcado contraste con eso carceralidad están infraestructuras comunitarias imaginadas por los organizadores sin viviendas, incluye eso construyó y sostuvo en Echo Park Lake
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(Dis)Placement: The Fight for Housing and Community After Echo Park Lake
Authored by the After Echo Park Lake research collective, this monograph analyzes processes of state-led displacement in Los Angeles. With a focus on the violent eviction of the unhoused community at Echo Park Lake, a public park in a gentrifying neighborhood of the city close to downtown, it draws attention to how political claims of housing placements legitimize such displacement but rarely result in housing outcomes. Through ethnographic research as well as analysis of homeless management data, it exposes this ruse of housing and draws attention to a condition of permanent displaceability for the city’s poor. A key finding of the monograph is that at a time of expanded housing resources underwritten by federal and state emergency and economic relief funds, there is a perverse investment of public funds in the criminalization of poverty and in the carceral containment of the unhoused. In sharp contrast to such carcerality are the infrastructures of community envisioned by unhoused organizers, including that which was built and sustained at Echo Park Lake