Cosmochemical constraints on the earliest evolution of the Solar System

Cosmochemistry, the study of chemical and isotopic signatures of meteorites, can provide direct constraints on the origin and evolution of the Solar System. As a discipline, it therefore, represents an important complement to fields like astronomy and astrophysics. Here I will review recent developments in cosmochemistry, and discuss several important implications for the dynamics of the early Solar System. From a cosmochemist's viewpoint, the evolution of the solar protoplanetary disk started with the formation of the oldest dated solids, Ca-Al-rich inclusions (CAIs), which formed ~4567 billion years ago. A second important step in early Solar System evolution is the formation of the first ~km-sized bodies known as planetesimals. Recent isotope studies of iron meteorites-metal samples of small planetesimal cores-demonstrate that core segregation in their parent bodies occurred within the first ~1-3 million years (Myr) after CAIs. Consequently, the formation of iron meteorite parent bodies occurred even earlier, well within

Speaker: Thomas ruijer, Lawrence Livermore National Labs