Results 21 to 30 of about 10,798 (236)

Metal compositions of carbonaceous chondrites [PDF]

open access: yesGeochimica et Cosmochimica Acta, 2022
FeNi metals represent an important fraction of chondritic components that remains relatively unexplored within most carbonaceous chondrite groups. The compositions of these metals can place constraints on the nature of their precursor materials as well as the physicochemical conditions of chondrule formation.
van Kooten, Elishevah   +5 more
openaire   +3 more sources

The effect of aqueous alteration and metamorphism in the survival of presolar silicate grains in chondrites [PDF]

open access: yes, 2008
Relatively small amounts (typically between 2-200 parts per million) of presolar grains have been preserved in the matrices of chondritic meteorites.
Bischoff   +31 more
core   +2 more sources

New carbonaceous chondrite Northwest Africa 11781 (CM2)

open access: yesЛитосфера, 2019
Research subject. The article presents the results of a study of a new meteorite Northwest Africa 11781.Material and methods. The material for the study was a fragment of a meteorite weighing 15.56 g, from which 4 transparent polished sections with a ...
K. A. Dugushkina, S. V. Berzin
doaj   +1 more source

Clasts in the CM2 carbonaceous chondrite Lonewolf Nunataks 94101: evidence for aqueous alteration prior to complex mixing [PDF]

open access: yes, 2013
Clasts in the CM2 carbonaceous chondrite Lonewolf Nunataks (LON) 94101 have been characterized using scanning and transmission electron microscopy and electron microprobe analysis to determine their degrees of aqueous alteration, and the timing of ...
Bischoff A.   +4 more
core   +1 more source

Meteorites and the RNA World: Synthesis of Nucleobases in Carbonaceous Planetesimals and the Role of Initial Volatile Content

open access: yesThe Astrophysical Journal, 2023
Prebiotic molecules, fundamental building blocks for the origin of life, have been found in carbonaceous chondrites. The exogenous delivery of these organic molecules onto the Hadean Earth could have sparked the polymerization of the first RNA molecules ...
Klaus Paschek   +5 more
doaj   +1 more source

Fluid evolution in CM carbonaceous chondrites tracked through the oxygen isotopic compositions of carbonates [PDF]

open access: yes, 2017
The oxygen isotopic compositions of calcite grains in four CM carbonaceous chondrites have been determined by NanoSIMS, and results reveal that aqueous solutions evolved in a similar manner between parent body regions with different intensities of ...
Alexander   +49 more
core   +2 more sources

Distant Formation and Differentiation of Outer Main Belt Asteroids and Carbonaceous Chondrite Parent Bodies

open access: yesAGU Advances, 2022
Volatile compositions of asteroids provide information on the Solar System history and the origins of Earth's volatiles. Visible to near‐infrared observations at wavelengths of 4) and low temperatures (10 au) and could be transported to their current ...
H. Kurokawa   +6 more
doaj   +1 more source

The Origin and Physico-Chemical Properties of Some Unusual Earth Rock Fragments

open access: yesApplied Sciences, 2022
In this paper, several researches were undertaken related to a violent phenomenon, characterized by a sonic boom, felt on an area of at least 500 km2, shortly followed by the fall of rock fragments that were then recovered from the ground.
Alexandru Cocean   +7 more
doaj   +1 more source

An asteroidal origin for water in the Moon

open access: yesNature Communications, 2016
Recent samples have shown that the Moon's interior, previously thought to be anhydrous, contains water, yet how this water was delivered is unclear. Here, using isotopic analyses and modelling, Barnes et al.
Jessica J. Barnes   +5 more
doaj   +1 more source

Stellar Outbursts and Chondrite Composition

open access: yesThe Astrophysical Journal, 2023
The temperatures of observed protoplanetary disks are not sufficiently high to produce the accretion rate needed to form stars, nor are they sufficient to explain the volatile depletion patterns in CM, CO, and CV chondrites and terrestrial planets.
Min Li   +5 more
doaj   +1 more source

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