Aluminum-26 chronology of dust coagulation and early solar system evolution.

ABSTRACT: Dust condensation and coagulation in the early solar system are the first steps toward forming the terrestrial planets, but the time scales of these processes remain poorly constrained. Through isotopic analysis of small Ca-Al-rich inclusions (CAIs) (30 to 100 μm in size) found in one of the most pristine chondrites, Allan Hills A77307 (CO3.0), for the short-lived ²⁶Al-²⁶Mg [t _1/2 = 0.72 million years (Ma)] system, we have identified two main populations of samples characterized by well-defined ²⁶Al/²⁷Al = 5.40 (±0.13) × 10^-5 and 4.89 (±0.10) × 10^-5. The result of the first population suggests a 50,000-year time scale between the condensation of micrometer-sized dust and formation of inclusions tens of micr

SUBMITTER: Liu MC 

PROVIDER: S-EPMC6739091 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature