Spectral Characterization of Bennu Analogs Using PASCALE: A New Experimental Set‐Up for Simulating the Near‐Surface Conditions of Airless Bodies

Autor: Neil Bowles, Devin L. Schrader, T. Warren, S. B. Calcutt, V. E. Hamilton, A. Clack, Jon Temple, K. L. Donaldson Hanna, Dante S. Lauretta, Timothy J. McCoy
Rok vydání: 2021
Předmět:
Atmospheres
010504 meteorology & atmospheric sciences
Planetary Atmospheres
Clouds
and Hazes
Permafrost
Atmospheric Composition and Structure
Biogeosciences
01 natural sciences
Meteorites and Tektites
Spectral line
Planetary Sciences: Solar System Objects
Physics and Chemistry of Materials
Earth and Planetary Sciences (miscellaneous)
Planetary Sciences: Astrobiology
Permafrost
Cryosphere
and High‐latitude Processes
Planetary Atmospheres
Composition of Meteorites
Meteorite Mineralogy and Petrology
Asteroids
Characterization (materials science)
Planetary Mineralogy and Petrology
Surfaces
Geophysics
Meteorite
Asteroid
Comets: Dust Tails and Trails
Bennu
Planetary Sciences: Comets and Small Bodies
airless bodies
Cryosphere
Composition
Research Article
spectroscopy
Materials science
Mineralogy
Planetary Geochemistry
Cryobiology
Geochemistry and Petrology
Chondrite
Comets
Emissivity
Spectroscopy
Planetary Sciences: Solid Surface Planets
Planetary Sciences: Fluid Planets
Mineralogy and Petrology
0105 earth and related environmental sciences
Albedo
Geochemistry
Space and Planetary Science
thermal infrared
Other
laboratory
Natural Hazards
Zdroj: Journal of Geophysical Research. Planets
ISSN: 2169-9100
2169-9097
DOI: 10.1029/2020je006624
Popis: We describe the capabilities, radiometric stability, and calibration of a custom vacuum environment chamber capable of simulating the near‐surface conditions of airless bodies. Here we demonstrate the collection of spectral measurements of a suite of fine particulate asteroid analogs made using the Planetary Analogue Surface Chamber for Asteroid and Lunar Environments (PASCALE) under conditions like those found on Earth and on airless bodies. The sample suite includes anhydrous and hydrated physical mixtures, and chondritic meteorites (CM, CI, CV, CR, and L5) previously characterized under Earth‐ and asteroid‐like conditions. And for the first time, we measure the terrestrial and extra‐terrestrial mineral end members used in the olivine‐ and phyllosilicate‐dominated physical mixtures under the same conditions as the mixtures and meteorites allowing us better understand how minerals combine spectrally when mixed intimately. Our measurements highlight the sensitivity of thermal infrared emissivity spectra to small amounts of low albedo materials and the composition of the sample materials. As the albedo of the sample decreases, we observe smaller differences between Earth‐ and asteroid‐like spectra, which results from a reduced thermal gradient in the upper hundreds of microns in the sample. These spectral measurements can be compared to thermal infrared emissivity spectra of asteroid (101955) Bennu's surface in regions where similarly fine particulate materials may be observed to infer surface compositions.
Key Points Thermal infrared spectra of fine particulate minerals, physical mixtures of those minerals, and meteorites were measured under simulated Bennu conditionsComparisons of mineral, physical mixture, and meteorite spectra highlight the spectral behavior when materials are mixed in increasing complexityAs albedo decreases the spectral effects due to thermal gradients due to the vacuum environment of airless bodies are reduced
Databáze: OpenAIRE
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