Thermal History of Asteroid Parent Bodies Is Reflected in Their Metalorganic Chemistry

Marco Matzka, Marianna Lucio, Basem Kanawati, Eric Quirico, Lydie Bonal, Stefan Loehle, and Philippe Schmitt-Kopplin

The Astrophysical Journal Letters https://doi.org/10.3847/2041-8213/ac0727

Abstract

Organo-magnesium compounds were shown to contribute significantly to the soluble carbon molecular complexityand diversity of meteorites, and their analysis increases our knowledge on carbon stabilization/sequestrationprocesses in the asteroidal parent body. Here we present a new group of sulfur-magnesium-carboxylates detectedusing ultra–high-resolution mass spectrometry in a variety of meteorites. These novel compounds show increasedabundance correlated with the thermal history of the asteroid parent bodies. By comparing the soluble organicextracts of 44 meteorites having experienced variable post-accretion history, we describe distinct organiccompound patterns of sulfur-magnesium-carboxylates in relation to their long- and short-duration thermal history.It is shown that the exceptional stability of these molecules enables survival of carbon under harsh thermalextraterrestrial conditions, even in the vitrified fusion crust formed during entry into the Earthʼs atmosphere.Sulfur-magnesium-carboxylates augment our understanding of parent body proceedings with regard to carbonsequestration and speciation in space.