Meteorites & Asteroids Archives

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 […]

α Cen’s orbit about the Galactic Centre viewed on the xy and yz planes (top row), as well as the orbits of the ejecta from α Cen viewed in a comoving frame (bottom row). Our Sun (Sol) is marked by a black hexagon and its orbital path indicated by a grey solid line (top row only). α Cen’s location and path are shown by a yellow star and blue solid line (top row only). In the bottom row, the comoving frame follows α Cen around its orbit while maintaining its orientation with the y-axis pointing towards the Galactic Centre (blue arrow) and α Cen’s velocity pointing in the -x direction (black arrow). This still frame is taken at t ≈ 3, 000 yr (that is, +3,000 years from the current epoch) after ∼ 100 Myr of integration. The colours of the ejecta represent the 3rd dimension of position, except that any particle that will at any point come within 100, 000 au of Sol are plotted in red. The full animation is available in the HTML version of this publication which shows the time evolution from t ≈ −100 Myr to t ≈ 10 Myr. The duration of the animation is 11 s. https://youtu.be/YABoYgNKr-I -- astro-ph.EP

Alpha Centauri, Comets and Asteroids, Interstellar, Meteorites & Asteroids, Panspermia, Press Release

A Case Study of Interstellar Material Delivery: Alpha Centauri

by Keith CowingFebruary 6, 2025February 6, 2025

Interstellar material has been discovered in our Solar System, yet its origins and details of its transport are unknown. Here we present α Centauri as a case study of the […]

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 […]

Distribution of planetesimals after 1 Gyr of evolution of giant planet migration. Data from Wong et al. (2023). -- astro-ph.EP

Astrogeology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Impact events, Jupiter, Mapping, Geodesy, Cartography, Bathymetry, Meteorites & Asteroids, Saturn, Status Report, Uranus

The Current Cratering Rate on the Regular Satellites of Jupiter, Saturn, and Uranus

by Keith CowingFebruary 4, 2025February 4, 2025

We aim to compute the impact rates for objects with a diameter of 1 km onto the regular satellites of Jupiter, Saturn and Uranus using our latest dynamical simulations of […]

Mg, Na phosphate occurs with Mg phyllosilicates largely free of micron-sized sulfide inclusions. The Mg,Na phosphate–Mg phyllosilicate veins rim large dolomite (Dol) grains that include magnetite (multielement Kα X-ray map; sample no. OREX-803085-100). Scale bar, 200 μm. -- Nature

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Comets and Asteroids, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Meteorites & Asteroids, Missions & Hardware, Planetary Protection & Biosafety, Press Release, Sample Return

Pristine Asteroid Samples Reveal Secrets Of The Ancient Solar System

by Keith CowingJanuary 30, 2025January 30, 2025

Curtin University researchers have gained an unprecedented glimpse into the early history of our solar system through some of the most well-preserved asteroid samples ever collected, potentially transforming our understanding […]

Canister containing material collected from asteroid Bennu placed inside the OSIRIS-REx sample return capsule. Credit: NASA/GSFC/Univ. of Arizona/Lockheed Martin

Exploring The Mysteries Of Asteroid Bennu

by Keith CowingJanuary 30, 2025January 30, 2025

During the past year, there’s been an unusual set of samples at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab): material gathered from the 4.5-billion-year-old asteroid Bennu when […]

a, Summed mass spectrum acquired from several ~100 μm grains mounted on a KBr window with mass peaks for ammonia (NH3), sodium (Na), formaldehyde (H2C=O), hydrogen sulfide (H2S) and potassium (K) indicated. Spectrum acquired by μ-L2MS using a vacuum UV photoionization at 118 nm. b, Optical mosaic of particle with yellow box demarking region mapped by μ-L2MS. c, Spatial map of ammonia distribution overlaid over optical image. The μ-L2MS laser beam spot size was 5 μm. -- Nature Astronomy

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Comets and Asteroids, Genomics, Proteomics, Bioinformatics, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Meteorites & Asteroids, Missions & Hardware, Planetary Protection & Biosafety, Press Release, Sample Return

Dust From asteroid Bennu: Building Blocks Of Life And Possible Habitats Were Widespread In Our Solar System

by Keith CowingJanuary 30, 2025January 30, 2025

It took two years for NASA’s OSIRIS-REx space probe to return from asteroid Bennu before dropping off a small capsule as it flew past Earth, which was then recovered in […]

Scanning electron microscope images of trona found in samples of the asteroid Bennu returned by NASA’s OSIRIS-REx mission. -- Credit Rob Wardell, Tim Gooding and Tim McCoy, Smithsonian.

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Comets and Asteroids, Icy Worlds, Meteorites & Asteroids, Missions & Hardware, Origin & Evolution of Life, Planetary Protection & Biosafety, Press Release, Sample Return

Traces Of Ancient Brine Discovered On Asteroid Bennu Contain Minerals Crucial To Life

by Keith CowingJanuary 30, 2025January 30, 2025

A new analysis of samples from the asteroid Bennu, NASA’s first asteroid sample captured in space and delivered to Earth, reveals that evaporated water left a briny broth where salts […]

In this video frame, Jason Dworkin holds up a vial that contains part of the sample from asteroid Bennu delivered to Earth by NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security – Regolith Explorer) mission in 2023. Dworkin is the mission’s project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Credit: NASA/James Tralie

Asteroid Bennu Sample Reveals A Mix Of Life’s Ingredients

by Keith CowingJanuary 29, 2025January 30, 2025

Studies of rock and dust from asteroid Bennu delivered to Earth by NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification and Security–Regolith Explorer) spacecraft have revealed molecules that, on our planet, […]

Meteorites & Asteroids

Planetesimal Impact Vapor Plumes and Nebular Shocks Form Chondritic Mixtures

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

A Case Study of Interstellar Material Delivery: Alpha Centauri

JWST Reveals Varied Origins Between Jupiter’s Irregular Satellites

The Current Cratering Rate on the Regular Satellites of Jupiter, Saturn, and Uranus

Pristine Asteroid Samples Reveal Secrets Of The Ancient Solar System

Exploring The Mysteries Of Asteroid Bennu

Dust From asteroid Bennu: Building Blocks Of Life And Possible Habitats Were Widespread In Our Solar System

Traces Of Ancient Brine Discovered On Asteroid Bennu Contain Minerals Crucial To Life

Asteroid Bennu Sample Reveals A Mix Of Life’s Ingredients

Astrobiologist Dale Andersen’s Antarctic Field Report: 3 November 2026: Digging Out and Packing Before the Traverse to Lake Untersee

When Should We Listen for Alien Signals? SETI Institute Scientists Turn to Game Theory.

Cheops Guest Observers Opportunity: JWST/HST Fast Track Proposals

Eyes on Exoplanets Software October Release Notes

A Mitochondrion-like Ribosome In An Insect Endosymbiont