Carbonaceous chondrites Archives - Page 2 of 3 - Astrobiology

BSE images showing examples of the textural groups of altered primary sulfides in CM1 chondrites—(a) pentlandite+phyllosilicate (2P) grain, (b) pyrrhotite+pentlandite+magnetite (PPM) grain, (c) pentlandite+serpentine (PS) grain, and (d) pyrrhotite+pentlandite+magnetite+serpentine (PPMS) grain. -- astro-ph.EP

Astrochemistry, Astrogeology, Meteorites & Asteroids, Press Release

The Fate of Primary Iron Sulfides in the CM1 Carbonaceous Chondrites: Effects of Advanced Aqueous Alteration on Primary Components

by Keith CowingJanuary 9, 2024January 9, 2024

We have carried out a SEM-EPMA-TEM study to determine the textures and compositions of relict primary iron sulfides and their alteration products in a suite of moderately to heavily-altered CM1 […]

Hayabusa2 sampling asteroid Ryugu

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Comets and Asteroids, Missions & Hardware, Press Release

Exploring The Origin Of Nucleosynthetic Isotope Variations In Ryugu Samples

by Keith CowingNovember 10, 2023November 13, 2023

The Hayabusa2 space mission by the Japan Aerospace Exploration Agency (JAXA) returned home with samples of the asteroid Ryugu that orbits the Sun between Earth and Mars.

Diagram of ε46Ti vs. ε50Ti for CB, CH and CR chondrite samples investigated in the present study. Bulk CR data for Acfer 139 (dark blue square) and NWA 801(gray square) are from this study and from Zhang et al. (2012), respectively. Literature data for different carbonaceous chondrite groups are stated as composite points averaging multiple samples within each group and are shown for comparison (white squares). The weighted ε50Ti– ε46Ti regression (solid black line) and related error envelopes were calculated using Isoplot, and include bulk meteorite data available from previous works. All reported uncertainties reflect 95% confidence intervals (95% CI). Literature data were taken from the recent compilation of Burkhardt et al. (2019) and references therein. -- astro-ph.EP

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Comets and Asteroids, Meteorites & Asteroids, Status Report

Age And Genetic Relationships Among CB, CH and CR Chondrites

by Keith CowingOctober 23, 2023October 20, 2023

The carbonaceous Bencubbin-like (CB), high-metal (CH), and Renazzo-like (CR) chondrites are metal-rich chondrites that have been suggested to be genetically linked and are sometimes grouped together as the CR chondrite […]

Experimentally measured outgassing composition of a 3 mg powdered Murchison sample from 200 °C–1200 ◦ C under a high-vacuum environment (∼10−4 Pa at lower temperatures and ∼10−3 Pa at higher temperatures; lower panel) compared with the outgassing trends of S and Zn under the same vacuum conditions from this study (upper panel). In the lower panel, the outgassing composition is shown as mole fractions of different outgassed species on a log scale as a function of temperature. The outgassing composition of Murchison was determined using a residual gas analyzer mass spectrometer that monitored the abundances (i.e., mole fractions) of the highly volatile outgassing species H2O, H2, CO, CO2, and H2S (see Thompson et al. 2021 for further details). Each species is labeled, and its mass number (in amu) is in parentheses. The dashed curves show equilibrium model-adjusted experimental outgassing compositions, which are the result of taking Thompson et al.’s (2021) experimental elemental outgassing results at intervals of 50 ◦ C and inputting those into the chemical equilibrium model of Figure 5 (see Schaefer & Fegley 2007, 2010 for details on the model) to recompute how the gas composition would speciate under equilibrium conditions. The upper panel shows the S and Zn outgassing trends from this study, expressed as these elements’ intensities, normalized to V and the average of the two unheated Murchison samples, for the residues heated under vacuum. -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Meteorites & Asteroids, Status Report

Outgassing Composition of the Murchison Meteorite: Implications for Volatile Depletion of Planetesimals and Interior-atmosphere Connections for Terrestrial Exoplanets

by Keith CowingOctober 4, 2023October 4, 2023

Outgassing is a central process during the formation and evolution of terrestrial planets and their atmospheres both within and beyond the solar system.

Ablation of Chelyabinsk meteorite sample in PWK1 plasma wind tunnel at the HEFDiG of the Institute of Space Systems at the University of Stuttgart. -- astro-ph.EP

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Comets and Asteroids, Imaging & Spectroscopy, Meteorites & Asteroids, Status Report

Analysis of CN Emission As A Marker Of Organic Compounds In Meteoroids Using Laboratory Simulated Meteors

by Keith CowingJuly 12, 2023July 12, 2023

Fragments of small solar system bodies entering Earth’s atmosphere have possibly been important contributors of organic compounds to the early Earth.

Chondrules and matrix in the Mokoia CV-chondrite with backscattered electrons. The darker chondrules indicate lower FeO contents. Bright spots are sulfides or metal. -- physics.geo-ph

Astrochemistry, Astrogeology, Comets and Asteroids, Meteorites & Asteroids, Status Report

The Origin Of Chondrules: Constraints From Matrix-Chondrule Complementarity

by Keith CowingJuly 6, 2023July 6, 2023

One of the major unresolved problems in cosmochemistry is the origin of chondrules, once molten, spherical silicate droplets with diameters of 0.2 to 2 mm.

Asteroid Itokawa as seen by the Hayabusa spacecraft. The peanut-shaped S-type asteroid measures approximately 1,100 feet in diameter and completes one rotation every 12 hours. -- JAXA

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Comets and Asteroids, Meteorites & Asteroids, Status Report

Asteroid Itokawa Once Supported a Hydrothermal System

by Keith CowingJune 23, 2023June 23, 2023

Ordinary chondrites (OCs) are the most abundant type of meteorites that fall to Earth. Compared to the carbonaceous chondrites, which commonly contain abundant hydrous minerals, OCs consist mainly of anhydrous […]

Cartoon illustrating our preferred scenario

Astrochemistry, Astrogeology, Comets and Asteroids, Meteorites & Asteroids, Status Report

Origin Of Isotopic Diversity Among Carbonaceous Chondrites

by Keith CowingMarch 8, 2023March 8, 2023

Carbonaceous chondrites are some of the most primitive meteorites and derive from planetesimals that formed a few million years after the beginning of the solar system.

asearch

Astrochemistry, Biochemistry & Organic Chemistry, Genomics, Proteomics, Bioinformatics, Interstellar, Status Report

A Search For Mid-IR Bands Of Amino Acids In The Perseus Molecular Cloud

by Keith CowingJanuary 19, 2023January 19, 2023

Amino acids are building-blocks of proteins, basic constituents of all organisms and essential to life on Earth.

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Origin & Evolution of Life, Panspermia, Press Release

SwRI Examines The Origins Of The Building Blocks Of Life

by Keith CowingJanuary 11, 2023January 11, 2023

A new study led by Southwest Research Institute Research Scientist Dr. Danna Qasim posits that interstellar cloud conditions may have played a significant role on the presence of key building […]