phyllosilicates Archives

a, STEM high-angle annular dark field (HAADF) + EDS image of Particle 2. A nitrogenous vein (green) is sandwiched between phyllosilicate regions (purple). A circular region shows the location of a selected area electron diffraction acquisition shown in b. The Pt and Si deposition and redeposition layers were created during the FIB processing. b, Selected area electron diffraction shows that the nitrogenous vein is amorphous. c, SEM backscatter plus EDS view of the larger particle before the FIB section was extracted. The substrate is diamond; only N was used for the green channel. The line shows the location of the FIB liftout; the dashed portion of the line is outside the field of view in a. d, EDS spectrum of the CNO peaks of the organic phase along with the fit used for quantification. dep, deposition; redep, redeposition.

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Cryobiology, Meteorites & Asteroids, Panspermia, Planetary Protection & Biosafety, Sample Return, Status Report

Nitrogen- And Oxygen-Rich Organic Material Indicative Of Polymerization In Pre-aqueous Cryochemistry On Bennu’s Parent Body

by Keith CowingDecember 21, 2025December 21, 2025

Nitrogen-containing organic compounds play key biological roles, and their identification in primitive astromaterials such as meteorites can shed light on the origin of life.

A drill-core section of the CCBH2 borehole showing a yellowish-red color resulting from the hydrothermal alteration process, with small carbonate mineralizations. In the bottom left, a fragment of the CCBH2 68–80 sample prepared for scanning electron microscope (SEM)—Raman analysis. -- Astrobiology via PubMed

Analog Studies, Arctic / Antarctic / Alpine, Astrogeology, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Desert Worlds, Habitable Zones, Status Report, Water/Hycean Worlds & Oceanography

Geochemical Mobility of Elements in Antarctic Environments Affected by CO2-Rich Hydrothermal Fluids: Astrobiological Implications

by Keith CowingNovember 17, 2025November 17, 2025

Hydrothermal systems are widespread in our solar system. Identification of alteration mineral assemblages on Mars and potentially in ocean worlds such as Enceladus suggests the existence of extensive hydrothermal fluid-igneous […]

Stitched BF-STEM micrograph of sample A0461-01-FIB02 with the typical observed OM morphologies marked. a – globular OM in various sizes and textures, b – fragmented globular OM, c – irregular OM, and d – diffuse OM between the phyllosilicate layers. -- astro-ph.EP

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Comets and Asteroids, Meteorites & Asteroids, Missions & Hardware, Origin & Evolution of Life, Press Release, Sample Return

The Nanoscale Molecular Chemistry Of Outer Solar System Organic Matter In Asteroid Ryugu

by Keith CowingJune 23, 2025June 23, 2025

The analysis of biorelevant molecules in returned mission samples such as from the carbonaceous asteroid (162173) Ryugu is key to unravelling the role of extraterrestrial organics in the evolution of […]

Spectral slope versus the size of the observed Pallas family members. The spectral slopes are calculated from Gaia’s Data Release 3 (DR3) observations (Gaia Collaboration et al. 2016, 2023b) and the sizes are obtained from the 2019 NEOWISE diameters and albedos archive. -- astro-ph.EP

Astrochemistry, Astrogeology, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Status Report

Near-infrared Spectroscopic Characterization Of The Pallas Family

by Keith CowingMarch 18, 2025March 18, 2025

The Pallas collisional family of asteroids, named after (2) Pallas, is notable for its high orbital inclination and the distinct blue color of Pallas and a few larger B-type family […]

Caption: At left: Steel is seen to corrode into siderite (FeCO3) when immersed in subcritical liquid carbon dioxide (LCO2). At right: Samples of albite (a plagioclase feldspar) and a sandstone core are observed to form red rhodochrosite (MnCO3) when exposed to supercritical CO2 in the presence of a water solution with potassium chloride and manganese chloride, with particularly strong reaction near the interface of the two solutions. In both experiments, water saturation is provided by floating LCO2 on the water. Under the lower pressure conditions characteristic of early Mars, the water would float on the LCO2. Credits: Photos courtesy of Todd Schaef/PNNL (left) and Earl Mattson/Mattson Hydrology (right).

Analog Studies, Arctic / Antarctic / Alpine, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Cryobiology, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Bathymetry, Mars, Origin & Evolution of Life, Press Release, Water/Hycean Worlds & Oceanography

Liquid On Mars Was Not Necessarily All Water

by Keith CowingDecember 7, 2024December 7, 2024

Dry river channels and lake beds on Mars point to the long-ago presence of a liquid on the planet’s surface, and the minerals observed from orbit and from landers seem […]

Additional bright deposits in shadowed craters proposed by Platz et al. (2016) shown at the highest available resolution in clear filter LAMO images, with the FC image number indicated. Images are shown as unprojected 150 × 150 pixel-sized crops with the contrast enhanced in shadowed areas. (a), (b), and (c) deposit #4. (d) and (e) #5. (f) #7. (g) #8. (h) #9. (i) #10. -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Caves, Craters, Mountains, Subsurface, Lava Tubes, Ceres, Icy Worlds, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Bathymetry, Missions & Hardware, Status Report, Water/Hycean Worlds & Oceanography

Spectral Properties Of Bright Deposits In Permanently Shadowed Craters On Ceres

by Keith CowingJuly 24, 2024July 24, 2024

Bright deposits in permanently shadowed craters on Ceres are thought to harbor water ice. However, the evidence for water ice presented thus far is indirect.

(A) MOLA image of Valles Marineris, including Ius Chasma. (B) THEMIS Day IR image of Ius Chasma including Geryon Montes and the bright layered materials containing the “doublet” spectral signatures. (C) HRSC DTM overlain by CTX and CRISM images of the doublet type unit on the southern wall of the northern valley of Ius Chasma. -- Icarus

Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Bathymetry, Mars, Status Report

Characterization of Aqueous Alteration and Formation of Salty Exposures at Ius Chasma, Mars

by Keith CowingJuly 21, 2024July 7, 2024

Intriguing outcrops in Ius Chasma provide a window into past aqueous processes in Valles Marineris, Mars. Hydrous sulfate minerals are abundant throughout this region, but one area in Ius Chasma […]

Bioenergetic results from the modeled simulations showing the feasibility of sulfate reduction, methanotrophy, methanogenesis, and anaerobic methane oxidation (AMO), based on Gibbs Energy quantification. All reactions at equilibrium are exergonic at all modeled conditions. Computed Gibbs Free Energy of Reaction is displayed as kJ/mol per e− transferred in the given reaction. -- Life

Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Habitable Zones, Mars, Meteorites & Asteroids, Status Report

Mineral Indicators of Geologically Recent Past Habitability on Mars

by Keith CowingJanuary 3, 2024January 3, 2024

We provide new support for habitable microenvironments in the near-subsurface of Mars, hosted in Fe- and Mg-rich rock units, and present a list of minerals that can serve as indicators […]

Optical reflectance spectra of 2004 GV9. Panel A: Here we compare our new GMOS reflectance spectra of 2004 GV9 both to each other and to coarse spectra derived from published single-epoch photometry (Rabinowitz et al. 2008; DeMeo et al. 2009; Fraser et al. 2015; Tegler et al. 2016). Hollow points in the GMOS spectra are either affected by incomplete background subtraction, telluric band residuals, proximity to the GMOS chip gaps, or a combination of these effects. All datasets are scaled to unit reflectance at 0.625 µm. We present all spectra calibrated with HD 124523 overlaid for direct comparison, and also offset for clarity. All offset spectra are offset vertically in increments of +0.2. Panel B: Here we show our 2004 GV9 spectra following division by a line fitted to them across their full wavelength coverage. Spectra from each epoch are offset vertically for clarity in increments of +0.1. Only spectra calibrated with HD 124523 are shown. Points affected by residuals of telluric absorption or imperfect background subtraction have been omitted. -- astro-ph.EP

Astrochemistry, Astrogeology, Astronomy & Telescopes, Comets and Asteroids, Imaging & Spectroscopy, Meteorites & Asteroids, Status Report

Hunting for Hydrated Minerals on Trans-Neptunian Objects

by Keith CowingDecember 20, 2023December 20, 2023

We present new optical reflectance spectra of three potentially silicate-rich Trans-Neptunian Objects (TNOs). These spectra were obtained with the aim of confirming past hints and detections of 0.7 micron absorption […]