High-velocity impact of micrometeorites: implication for evolution of asteroid regolith

2016 Fiscal Year Final Research Report

• Project/Area Number: 26800235
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Solid earth and planetary physics
• Research Institution: Okayama University
• Principal Investigator: Shimaki Yuri 岡山大学, 惑星物質研究所, 助手 (60710548)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 衝撃変成 / クレーター / 普通コンドライト / 小惑星

Outline of Final Research Achievements

We carried out high-velocity impact-experiments of metal and silicate projectile into regolith of silicates including ordinary chondrites by vertical and horizontal two-stage light-gas-gun in the Institute of Space and Astronautical Science to examine crater formation process and physicochemical evolution of regolith on asteroid surface. A new vacuum impregnation system for embedding crater on regolith was developed. Impact products distribute at depth of two times of projectile diameter from surface. Impact melt consists of sub-micron silicates and metal spherules with trace-element abundance similar to bulk composition.

Free Research Field

数物系科学