Chondrule formation via extended winds in the early solar system

TL;DR

This paper proposes that extended winds from protostellar disks can account for the high-temperature formation of chondrules in the early solar system, reconciling meteorite evidence with star formation observations.

Contribution

It introduces models of disk winds as sites for chondrule formation, providing a new mechanism consistent with astrophysical constraints.

Findings

Disk wind models can produce the necessary thermal conditions for chondrule formation.

Protostellar disk winds are plausible environments for high-temperature processing of dust.

The proposed mechanism aligns meteorite evidence with star formation observations.

Abstract

Chondrite meteorites are believed to represent the building blocks of the solar nebula, out of which our solar system formed. They are a mixture of silicate and oxide objects (chondrules and refractory inclusions) that experienced extremely high temperatures, set in a matrix that remained relatively cold. The prevalence of chondrites suggests that they formed through a very general process, closely related to stellar and planet formation, however the nature and properties of the responsible mechanism have remained unclear for many decades. The evidence for a hot solar nebula provided by chondrules and refractory inclusions is, however, seemingly at odds with astrophysical observations of forming stars. These strongly indicate that protostellar disks - the inspiralling disks of gas and dust out of which stars and planets form - are relatively cool, and exhibit typical temperatures that are insufficient to melt and vapourise silicate minerals at the radial distances sampled by chondrule-bearing meteorites in the main asteroid belt. Here we present calculations of the dynamical and thermal structure of protostellar disks that accelerate a wind from the disk surfaces. These winds are commonly associated with young stellar objects and are the analogues of the early solar system. We also present models of the processing of dust particles in such winds, showing that these outflows are suitable sites for chondrule formation.