Planetesimal formation induced by the gas disk dispersal

2020 Fiscal Year Final Research Report

• Project/Area Number: 15K05268
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Solid earth and planetary physics
• Research Institution: Kyushu University
• Principal Investigator: Sekiya Minoru 九州大学, 理学研究院, 名誉教授 (60202420)
• Project Period (FY): 2015-04-01 – 2021-03-31
• Keywords: 惑星 / 惑星形成 / 太陽系 / 隕石 / 微惑星

Outline of Final Research Achievements

The astronomical observations show that there are disks of gas and solid particles around forming stars. The primitive meteorites made mainly of chondrules that are mm-sized spherical rocks. The most promising process for the formation of planetesimals is the streaming instability, which boost the concentration of solid particles when the drag force between the gas and solid particles act in a disk. This work elucidates that the condition for the particles concentration is expressed by two parameters, which enabled us to apply the condition for various protoplanetary disks.

Free Research Field

宇宙惑星科学

Academic Significance and Societal Importance of the Research Achievements

原始惑星系円盤内で固体微粒子がストリーミング不安定性により濃集する条件を２つのパラメータで表現できたことは、太陽系だけでなく宇宙で普遍的に起こっている星形成過程における惑星形成についての研究を進めるために役立つ。ガスと固体微粒子からなる系は惑星形成に限らず存在するので、他の分野での固体微粒子の濃集プロセスへの応用も可能であると期待される。