The Origin and Evolution of Organic Matter in Carbonaceous Chondrites and Links to Their Parent Bodies

Abstract

The nature of organic matter in meteorites reveals information about early solar system chemistry and the histories of parent bodies as recorded in the effects of physical and chemical processes that occurred over the past 4.5 billion years. Asteroids and their fragments impact the Earth with ~40 million kg of material each year and contributed to the inventory of organics available for the origin of life. Analyses of primitive carbonaceous chondrites over the last five decades have revealed a major insoluble organic component, as well as a complex and highly diverse suite of soluble organic molecules that includes aliphatic and aromatic hydrocarbons, carboxylic acids, hydroxy acids, N-heterocycles, polyols, amino acids, amines, and many other molecules that have not yet been identified. Thermal and aqueous alteration in primitive asteroids played an important role in the formation and destruction organics, including amplification of Lamino acid and D-sugar acid enantiomeric excesses that may have contributed to the origin of homochirality in life on Earth.

Evaluation of terrestrial carbonaceous matter aromatization by Raman spectroscopy and its application to C chondrites

“…Equations were employed on the data set of Raman spectra from carbonaceous chondrites compiled in Table in supporting information. The chondrites were separated in three groups, including (1) chondrites that present aqueous alteration; (2) chondrites that were subjected to anhydrous heating (“metamorphism” sensu Glavin et al 2018); and (3) chondrites that suffered graphitization (highly structured polyaromatic carbonaceous matter sensu Bonal et al 2016).…”

“…Raw data along with C content, N/C and S/C elemental ratios, and δ 13 C; δ 15 N; δD; and δ 18 O isotopic compositions can be found in Table in supporting information, data sets from Alexander et al (2007, 2010, 2014); Chan et al (2018, 2019b); Oba and Naraoka (2009); Okumura and Mimura (2011); Remusat et al (2019); and Yabuta et al (2007). The aqueous alteration group (AA) comprises classes C2‐3‐ung, CI1, CM1‐2‐an, CR1‐2‐an, and xenolithic halite; the metamorphic (MET) group comprises the remaining classes (based on the classification proposed by Glavin et al 2018). The elemental ratios evolution of anhydrous pyrolysis (Oba and Naraoka 2009; Remusat et al 2019) and hydrous pyrolysis series (Yabuta et al 2007; Okumura and Mimura 2011) of OM from chondrites were plotted for comparison.…”

“…This wide range of OM aromatization is also observed in carbonaceous chondrites, primitive meteorites that represent some of the most ancient cosmo‐material available for laboratory analysis (Bonal et al 2016; Glavin et al 2018). The OM in meteorites reveals information about early solar system chemistry, parent body histories, and timescales for nucleosynthesis and circumstellar dust formation (Glavin et al 2018). Considering that chondritic meteorites did not experience melting and igneous differentiation in their asteroidal parent bodies, they largely preserve records of physical and chemical processes in the solar nebula (McCoy et al 2006).…”

New insights into the heterogeneity of the Tagish Lake meteorite: Soluble organic compositions of variously altered specimens

“…The origin and distribution of meteoritic organic compounds (e.g., amino acids, carboxylic acids, aldehydes, and ketones) are of interest for understanding the origin of life on Earth and the potential for life elsewhere, as these compounds are known precursors to several key biological molecules (Botta and Bada ; Sephton ; Glavin et al. ). Amino acids, the building blocks of protein, may be synthesized via the Strecker‐cyanohydrin reaction (Peltzer et al.…”

“…The soluble organic content of Tagish Lake and other carbonaceous chondrites provide a chemical record of the prebiotic synthesis reactions that took place throughout the early solar system during its formation and during subsequent parent body alteration. The origin and distribution of meteoritic organic compounds (e.g., amino acids, carboxylic acids, aldehydes, and ketones) are of interest for understanding the origin of life on Earth and the potential for life elsewhere, as these compounds are known precursors to several key biological molecules Sephton 2002;Glavin et al 2018). Amino acids, the building blocks of protein, may be synthesized via the Strecker-cyanohydrin reaction (Peltzer et al 1984).…”