Crystallization of Cosmic Materials under Microgravity 4.6 Billion Years Ago

Abstract

A　crystallization process in the early solar nebula 4.6 billion years ago has been simulated by using microgravity and levitation methods through the investigation of the formation mechanism of chondrules, which are mm-sized spherical crystals, formed from silicate melt droplets during the formation of the solar system. Although the time required for the crystallization of chondrules has been believed to be several hours to days, our results strongly suggest this crystallization time be much shorter, a few seconds. The chondrules were crystallized from large supercooled or hypercooled melts. This short-time crystallization hypnosis has been supported by numerical simulations based on shock wave model.