chondrites Archives - Astrobiology

Optical depth spectrum and ENIIGMA best-fit model for the 4.0-4.45 µm region and its separate components. Major gas lines are labeled. The inset zooms in on the HDO ice feature. -- astro-ph.EP

Astrochemistry, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Icy Worlds, Imaging & Spectroscopy, Interstellar, Press Release, Water/Hycean Worlds & Oceanography

First Detection Of HDO Ice In A Protoplanetary Disk

by Keith CowingJune 11, 2026June 11, 2026

Protoplanetary disks are the birthplace of planets and planetary systems. Investigating the molecular inventory of disks is key to linking the chemical evolution of the interstellar medium and the makeup […]

An artist's impression of a disk of gas and dust formed during the birth of the sun. Credit: NASA/FUSE/Lynette Cook

Astrochemistry, Astrogeology, Comets and Asteroids, Exoplanets, -moons, -comets, Habitable Zones, Mars, Mercury, Meteorites & Asteroids, Press Release, Venus

New Experiments And Modeling On Iron Meteorites Provide Insight Into Young Solar System And Earth’s Building Blocks

by Keith CowingJune 4, 2026June 4, 2026

Habitable planets require life-essential elements, like nitrogen and phosphorus. Understanding how those elements ended up in a planetary body can give insight into the formation of the solar system and […]

Iron isotopic compositions of CI chondrites, CV chondrites, and terrestrial rocks. The μ 54Fe and μ58Fe data for different sample types (see legend) from this study (solid symbols) together with data from previous works (open symbols) (Table S1). Error bars indicate 95% confidence intervals. CV chondrites have similar μ 58Fe but elevated μ 54Fe compared to terrestrial samples. CI chondrites have similar μ 54Fe but elevated μ 58Fe compared to terrestrial samples. -- astro-ph.EP

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Meteorites & Asteroids, Press Release

Iron Isotope Anomalies And The Origin Of The Earth

by Keith CowingMarch 30, 2026March 30, 2026

Understanding the origin of the Earth requires determining the original formation location of its building material.

NanoSIMS ratio and ion images (top images) of a region containing a 17O-rich presolar silicate grain (arrows). The elemental maps and spectra from SEM-EDX analysis confirm the grain is a ferromagnesian silicate. -- Nature Astronomy via PubMed

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Comets and Asteroids, Imaging & Spectroscopy, Meteorites & Asteroids, Missions & Hardware, Sample Return, Status Report

The Variety And Origin Of Materials Accreted By Bennu’s Parent Asteroid

by Keith CowingDecember 24, 2025December 24, 2025

The first bodies to form in the Solar System acquired their materials from stars, the presolar molecular cloud and the protoplanetary disk.

a) Mn/Na vs. Mn/Mg and b) Mn/Na vs. K/Li ratios among planetary bodies. The coloured curves denote the evolution of the composition of an evaporation residue calculated using eq. 35 at 1100 K (purple), 1500 K (blue), 2000 K (green) and 2500 K (red) at a fixed relative oxygen fugacity (∆IW-1, except for 1100 K, which was calculated at ∆IW-6, see text), with numbers denoting the fraction of Mn loss undergone by the body. The black dashed lines connect equal degrees of Mn loss at different temperatures. The solid black curves trace a binary mixture of a volatile-depleted end-member with 90 % Mn loss and a CI-like end-member. The small numbers denote the mass fraction of CI in the mixture. On a), only the volatile-depleted end-member at 1500 K is shown due to clarity, whereas in b) the end-members are taken at the three temperatures, and the dotted grey lines connect equal fractions of CI material. The grey point gives the composition of the Earth assuming 50 % of its Mn budget resides in the core [see Siebert et al., 2018]. The grey field denotes the compositional range of chondrites [Wasson and Kallemeyn, 1988; Siebert et al., 2018]. -- astro-ph.EP

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

Physicochemical Controls On The Compositions Of The Earth And Planets

by Keith CowingDecember 11, 2025December 10, 2025

Despite the fact that the terrestrial planets formed from the protoplanetary disk, their compositions show marked departures from that of solar nebula condensates.

Artist impression of solar system formation. Presolar grains are tiny, solid grains of primitive solar system material that originated before the formation of the Sun. They have been found in many places, including interplanetary dust, meteorites, and even samples from the comet Wild-2 that were returned to Earth by NASA's Stardust mission. Image credit: Gemini Observatory/AURA/Lynette Cook via NASA Astrobiology

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Meteorites & Asteroids, Status Report

Origin Of Moderately Volatile Elements In Earth

by Keith CowingMay 13, 2025May 13, 2025

The bulk silicate Earth (BSE) is depleted in moderately volatile elements, indicating Earth formed from a mixture of volatile-rich and -poor materials.

1D spherical vapor plume expansion and flow reversal. Example vapor plume evolution starting with an 80 GPa water sphere of radius 25 km, expanding into a dust-free nebular gas at 10−6 bars. In panels A-D, the thick dashed line represents the material boundary between the inner water vapor plume and outer nebular gas. The color shading presents radial velocity (A), pressure (B), density (C), and temperature (D) versus time. The streamlines (thin grey in A; thin white in B-D) indicate the flow history of the gas and any fully coupled dust. The nebular shock generated by the expanding vapor plume creates a transiently hot nebular environment that expands and cools on the time scale of hours. The inset (E) is a close-in view of the initial hot nebular shock front. In panel C, points A-E are used to illustrate size sorting in the outward flow in section 6. We propose chondrules form and cool in the transiently shocked (dusty) nebular gas. The supplemental materials contain an interactive version of this figure. -- astro-ph.EP

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Impact events, Meteorites & Asteroids, Status Report

Planetesimal Impact Vapor Plumes and Nebular Shocks Form Chondritic Mixtures

by Keith CowingMarch 14, 2025March 14, 2025

The origin of chondrules, and the chondritic sedimentary rocks that dominate the meteoritic record, is a long-standing problem in planetary science. Here, we develop a physical model for the formation […]

Mid-infrared spectra of CO3s. The spectra correspond to milled samples, with grain size between 1 - 10 µm. The data presented are normalized to the maximum in the range of 8 - 12 µm and vertically shifted for a better appreciation of shape and peaks. The vertical lines correspond to characteristic absorption bands of different minerals: light blue, for the water bands (OH); green for olivine bands, orange for the pyroxene bands, and red for plagioclase (Chihara et al. 2002; Koike et al. 2003b; Beck et al. 2014; Chihara & Koike 2017). -- astro-ph.EP

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Comets and Asteroids, Imaging & Spectroscopy, Interstellar, Meteorites & Asteroids, Press Release

Mid-infrared Absorption Spectra and Mass Absorption Coefficients for 23 Chondrites: Dependence On Composition and Grain Size

by Keith CowingMarch 11, 2025March 11, 2025

We present mid-infrared transmission spectra from 2 to 23 microns of the 23 Atacama Desert chondrites of different types (carbonaceous Ornans and ordinary of H, L, and LL groups) as […]

Irregular satellite orbital inclinations and semimajor axes (normalized to Jupiter’s Hill radius). Family groupings are given as indicated. The prograde population is dominated in mass and number by the Himalia family. The retrograde population is categorized into three orbital families, with the more widely dispersed Pasiphae and Ananke families and the more tightly grouped Carme family. This work studies the Himalia, Carme, Pasiphae, and Ananke families, as well as the isolated satellite Themisto. Orbital parameters from JPL Horizons. -- astro-ph.EP

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Jupiter, Meteorites & Asteroids, Status Report

JWST Reveals Varied Origins Between Jupiter’s Irregular Satellites

by Keith CowingFebruary 5, 2025February 5, 2025

We report observations of eight Jovian irregular satellites with JWST’s NIRSpec instrument: Himalia, Elara, Pasiphae, Sinope, Lysithea, Carme, Ananke, and Themisto. Irregular satellite families, which are presumed to have formed […]

The predicted uncompressed density of the Pluto-Charon system (colored curves) as the fraction of the protosolar C inventory contained in refractory organics increases from 0% to 100%, assuming the canonical protosolar abundances in Lodders 2021 (L21, see Table 1). The horizontal black dashed line represents the average uncompressed density of the system ∼ 1800 kg m−3 (Barr & Schwamb 2016; McKinnon et al. 2017), taken to be the most representative value we have for the bulk composition of large KBOs. The gray area shows the 3σ uncertainty (± 20 kg m−3 , Brozovi´c et al. 2015, McKinnon et al. 2017, Nimmo et al. 2017). -- astro-ph.EP

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

A Broad Set of Solar and Cosmochemical Data Indicates High C-N-O Abundances For Our Solar System

by Keith CowingSeptember 16, 2024September 16, 2024

We examine the role of refractory organics as a major C carrier in the outer protosolar nebula and its implications for the compositions of large Kuiper belt objects (KBOs) and […]