cosmochemistry Archives

Left column: Both colorbar and isolines show fit quality as a function of planetesimal radius R and accretion time for CR1-3 chondrites (first row) and the Flensburg chondite (second row). Best-fit accretion times correspond from top to bottom to Ma and Ma. The exemplary parent bodies from the respective minimum fit quality regions with km and Ma and km and Ma, from top to bottom, are indicated with red dots. Right column: Thermal evolution at the best-fit depths d of respective meteorites for representative best-fit parent bodies indicated by red dots in the left column. Dashed red lines show the maximum metamorphic temperature estimates from petrological constraints (see also supplementary material). Color patches show PB accretion time intervals. The accretion time of the CR clan Tafassite PB is included for completeness. -- Scientific Reports

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Ceres, Comets and Asteroids, Exoplanets, -moons, -comets, Habitable Zones, Icy Worlds, Mars, Mercury, Meteorites & Asteroids, Press Release, Water/Hycean Worlds & Oceanography

The Building Materials For Water-rich Planets In The Early Solar System

by Keith CowingJuly 25, 2024July 25, 2024

Age data for certain classes of meteorite have made it possible to gain new findings on the origin of small water-rich astronomical bodies in the early solar system. These so-called […]

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.

Condensation predictions (a) and experimental results (b). Red dash-dot line indicates the T below which olivine is stable, black dashed line the T below which metal alloy is stable. Black dots in (b) indicate experiments at composition and T of condensed oxide assemblages of (a), omitting metal alloy. (a) Adapted from Ebel (2006, Plate 10), (b) Adapted from Ustunisik et al. (2014). -- astro-ph.EP

Astrochemistry, Astrogeology, Meteorites & Asteroids, Status Report

Condensation Calculations In Planetary Science And Cosmochemistry

by Keith CowingJune 28, 2023June 28, 2023

Cool a piece of the Sun to 1000 K at one millibar pressure to yield a mineral assemblage consistent with those found in the most primitive meteorites. This is an […]