S. M. Clegg
A5066233270- Planetary Science and Exploration
- Laser-induced spectroscopy and plasma
- Astro and Planetary Science
- Space Exploration and Technology
- Analytical chemistry methods development
- Geochemistry and Geologic Mapping
- Isotope Analysis in Ecology
- Mercury impact and mitigation studies
- Methane Hydrates and Related Phenomena
- Hydrocarbon exploration and reservoir analysis
- Geology and Paleoclimatology Research
- Cultural Heritage Materials Analysis
- Atmospheric and Environmental Gas Dynamics
- Spectroscopy and Chemometric Analyses
- Spectroscopy Techniques in Biomedical and Chemical Research
- Space Science and Extraterrestrial Life
- Geochemistry and Elemental Analysis
- Geological and Geochemical Analysis
- Mass Spectrometry Techniques and Applications
- Advanced Chemical Physics Studies
- Atmospheric Ozone and Climate
- Mineral Processing and Grinding
- Spectroscopy and Laser Applications
- Paleontology and Stratigraphy of Fossils
- Advanced Chemical Sensor Technologies
Los Alamos National Laboratory
2016-2025
Los Alamos National Security (United States)
2021-2024
Institut de Recherche en Astrophysique et Planétologie
2021-2023
Purdue University West Lafayette
2023
Centre National de la Recherche Scientifique
2022-2023
Université de Toulouse
2023
Université Toulouse III - Paul Sabatier
2023
University of South Carolina
2022
University of Southampton
2021
United States Geological Survey
2021
Sedimentary rocks at Yellowknife Bay (Gale crater) on Mars include mudstone sampled by the Curiosity rover. The samples, John Klein and Cumberland, contain detrital basaltic minerals, calcium sulfates, iron oxide or hydroxides, sulfides, amorphous material, trioctahedral smectites. smectite has basal spacing of ~10 angstroms, indicating little interlayer hydration. Cumberland both ~13.2 angstroms. larger suggests a partially chloritized magnesium facilitating H2O retention. Basaltic minerals...
The ChemCam instrument suite on the Mars Science Laboratory (MSL) rover Curiosity provides remote compositional information using first laser-induced breakdown spectrometer (LIBS) a planetary mission, and sample texture morphology data micro-imager (RMI). Overall, supports MSL with five capabilities: classification of rock soil characteristics; quantitative elemental compositions including light elements like hydrogen some to which LIBS is uniquely sensitive (e.g., Li, Be, Rb, Sr, Ba);...
The Mars Science Laboratory rover Curiosity scooped samples of soil from the Rocknest aeolian bedform in Gale crater. Analysis with Chemistry and Mineralogy (CheMin) x-ray diffraction (XRD) instrument revealed plagioclase (~An57), forsteritic olivine (~Fo62), augite, pigeonite, minor K-feldspar, magnetite, quartz, anhydrite, hematite, ilmenite. phases are present at, or near, detection limits. also contains 27 ± 14 weight percent amorphous material, likely containing multiple Fe 3+ -...
The ChemCam instrument package on the Mars Science Laboratory rover, Curiosity, is first planetary science to employ laser-induced breakdown spectroscopy (LIBS) determine compositions of geological samples another planet. Pre-processing spectra involves subtracting ambient light background, removing noise, electron continuum, calibrating for wavelength, correcting variable distance target, and applying a wavelength-dependent correction response. Further processing data uses multivariate...
Sedimentary rocks examined by the Curiosity rover at Yellowknife Bay, Mars, were derived from sources that evolved an approximately average martian crustal composition to one influenced alkaline basalts. No evidence of chemical weathering is preserved, indicating arid, possibly cold, paleoclimates and rapid erosion deposition. The absence predicted geochemical variations indicates magnetite phyllosilicates formed diagenesis under low-temperature, circumneutral pH, rock-dominated aqueous...
The ChemCam instrument, which provides insight into martian soil chemistry at the submillimeter scale, identified two principal types along Curiosity rover traverse: a fine-grained mafic type and locally derived, coarse-grained felsic type. component is representative of widespread soils similar in composition to dust. It possesses ubiquitous hydrogen signature spectra, corresponding hydration amorphous phases found by CheMin instrument. This likely accounts for an important fraction global...
Abstract The Curiosity rover has analyzed abundant light‐toned fracture‐fill material within the Yellowknife Bay sedimentary deposits. ChemCam instrument, coupled with Mastcam and ChemCam/Remote Micro Imager images, was able to demonstrate that these fracture fills consist of calcium sulfate veins, many which appear be hydrated at a level expected for gypsum bassanite. Anhydrite is locally present found in location characterized by nodular texture. An intricate assemblage veins crosses...
Abstract On the NASA 2020 rover mission to Jezero crater, remote determination of texture, mineralogy and chemistry rocks is essential quickly thoroughly characterize an area optimize selection samples for return Earth. As part Perseverance payload, SuperCam a suite five techniques that provide critical complementary observations via Laser-Induced Breakdown Spectroscopy (LIBS), Time-Resolved Raman Luminescence (TRR/L), visible near-infrared spectroscopy (VISIR), high-resolution color imaging...
Abstract The Scanning Habitable Environments with Raman and Luminescence for Organics Chemicals (SHERLOC) is a robotic arm-mounted instrument on NASA’s Perseverance rover. SHERLOC has two primary boresights. Spectroscopy boresight generates spatially resolved chemical maps using fluorescence spectroscopy coupled to microscopic images (10.1 μm/pixel). second Wide Angle Topographic Sensor Operations eNgineering (WATSON); copy of the Mars Science Laboratory (MSL) Hand Lens Imager (MAHLI) that...
Before Perseverance, Jezero crater's floor was variably hypothesized to have a lacustrine, lava, volcanic airfall, or aeolian origin. SuperCam observations in the first 286 Mars days on revealed and intrusive terrain with compositional density stratification. The dominant lithology along traverse is basaltic, plagioclase enrichment stratigraphically higher locations. Stratigraphically lower, layered rocks are richer normative pyroxene. lowest observed unit has highest inferred olivine-rich...
At Gale crater, Mars, ChemCam acquired its first laser-induced breakdown spectroscopy (LIBS) target on Sol 13 of the landed portion mission (a is a Mars day).
Abstract The Curiosity rover observed high Mn abundances (>25 wt % MnO) in fracture‐filling materials that crosscut sandstones the Kimberley region of Gale crater, Mars. correlation between and trace metal plus lack elements such as S, Cl, C, reveals these deposits are oxides rather than evaporites or other salts. On Earth, environments concentrate deposit minerals require water highly oxidizing conditions; hence, findings suggest similar processes occurred on Based strong association...
Abstract Volatiles and especially halogens (F Cl) have been recognized as important species in the genesis melting of planetary magmas. Data from Chemical Camera instrument on board Mars Science Laboratory rover Curiosity now provide first situ analyses fluorine at surface Mars. Two principal F‐bearing mineral assemblages are identified. The is associated with high aluminum low calcium contents, which phase an aluminosilicate. It found conglomerates may indicate petrologically evolved...
Abstract Diagenetic silica enrichment in fracture‐associated halos that crosscut lacustrine and unconformably overlying aeolian sedimentary bedrock is observed on the lower north slope of Aeolis Mons Gale crater, Mars. The diagenetic colocated with detrital yet extends into a considerably younger, draping sandstone, implying postdates enrichment. A causal connection between implies water was present subsurface crater long after deposition sediments it mobilized amorphous precipitated along...
SHERLOC is an arm-mounted fluorescence and Raman spectrometer that was recently selected to be part of the payload for next proposed NASA rover mission Mars, scheduled launch in 2020. enables non-contact, spatially resolved, high sensitivity detection characterization organics minerals on Martian surface. The investigation goals are assess past aqueous history, detect presence preservation potential biosignatures, support selection samples caching return Earth.
Abstract The surface of Mars has long been considered a relatively oxidizing environment, an idea supported by the abundance ferric iron phases observed there. However, compared to iron, manganese is sensitive only high redox potential oxidants, and when concentrated in rocks, it provides more specific indicator aqueous environments. Observations from ChemCam instrument on Curiosity rover indicate abundances some rock targets that are 1–2 orders magnitude higher than previously Mars,...