Experimental study on atmospheric escape from terrestrial planets caused by asteroid impacts

2017 Fiscal Year Final Research Report

• Project/Area Number: 16H06719
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Solid earth and planetary physics
• Research Institution: The University of Tokyo
• Principal Investigator: Tatsumi Eri 東京大学, 大学院理学系研究科(理学部), 特任研究員 (60623197)
• Project Period (FY): 2016-08-26 – 2018-03-31
• Keywords: 小惑星 / 衝突実験 / 探査 / イトカワ

Outline of Final Research Achievements

The goal of this study is to evaluate the physical effect of impacts of small bodies, such as asteroids and comets.There are two sub-theme in this study: 1) Laser ablation experiment to observe the motion and interaction of vapor cloud and atmosphere, 2) Asteroid mass evolution based on spacecraft observation. We used Schlieren method for visualization of vapor and atmosphere. However, due to impact luminescence and low sensitivity of detector, we need to develop our observation method to detect the motion of vapor. On the other hand, the mass evolution of small asteroids, which are too faint to observe from ground, as impactors to terrestrial planets are also important. We conducted impact experiments and derived new crater scaling law for such small asteroids, which can be a clue for mass evolution of small asteroids in last stage. Moreover, from Hayabusa spectral and morphological analyses, the first direct footprint of transition from the main belt to near Earth was found.

Free Research Field

宇宙惑星科学