Meteorites and the physico-chemical conditions in the early solar nebula

TL;DR

This paper reviews how chondritic meteorites reveal the physico-chemical conditions of the early solar nebula, combining mineralogical, isotopic, and astrophysical data to understand solar system formation.

Contribution

It synthesizes mineralogical, isotopic, and astrophysical evidence to elucidate the conditions and processes in the early solar nebula, integrating recent sample return data and models.

Findings

High-temperature formation of chondrules and refractory inclusions

Oxygen isotopic variations indicating nebular photochemistry

Organic matter and hydrogen isotopes reveal cold cloud chemistry

Abstract

Chondritic meteorites constitute the most ancient rock record available in the laboratory to study the formation of the solar system and its planets. Detailed investigations of their mineralogy, petrography, chemistry and isotopic composition and comparison with other primitive solar system samples such as cometary dust particles have allowed through the years to decipher the conditions of formation of their individual components thought to have once been free-floating pieces of dust and rocks in the early solar nebula. When put in the context of astrophysical models of young stellar objects, chondritic meteorites and cometary dust bring essential insights on the astrophysical conditions prevailing in the very first stages of the solar system. Several exemples are shown in this chapter, which include (1) high temperature processes and the formation of chondrules and refractory inclusions, (2) oxygen isotopes and their bearing on photochemistry and large scale geochemical reservoirs in the nebula, (3) organosynthesis and cold cloud chemistry recorded by organic matter and hydrogen isotopes, (4) irradiation of solids by flares from the young Sun and finally (5) large scale transport and mixing of material evidenced in chondritic interplanetary dust particles and samples returned from comet Wild2 by the Stardust mission.