Japan Geoscience Union Meeting 2018

Presentation information

[JJ] Oral

P (Space and Planetary Sciences) » P-PS Planetary Sciences

[P-PS08] Planetary Sciences

Mon. May 21, 2018 10:45 AM - 12:15 PM International Conference Room (IC) (2F International Conference Hall, Makuhari Messe)

convener:Takaya Okamoto(Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency), Kenji Kurosaki(Department of Physics, Nagoya University), Chairperson:Hosono Natsuki(京都大学), Okamoto Takaya(千葉工大惑星探査研究センター)

11:45 AM - 12:00 PM

[PPS08-17] Numerical simulations of the giant impact onto the magma ocean

*Natsuki Hosono1,2, Shun-ichiro Karato3, Junichiro Makino4,2, Takayuki R. Saitoh5 (1.Japan Agency for Marine-Earth Science and Technology, 2.Advanced Institute for Computational Science, RIKEN, 3.Yale Univ., 4.Kobe Univ., 5.Earth-Life Science Institute)

Keywords:Giant Impact, Moon

The Giant Impact (GI) hypothesis is one of the most important phenomena in the planetary science and geoscience as the origin of the Moon.
According to this scenario, a Mars-sized impactor hit the proto-Earth and generate circumterrestrial debris disc, which is later accumulated into the Moon.
Lately, however, the GI has been challenged; the isotope ratios of particular elements show nearly identical values for the bulk component of the Earth and that of the Moon.
This means that the circumterrestrial debris disc should come from the proto-Earth.
However, to date, almost all of the numerical simulations of canonical GIs has concluded that the post-impact disc tends to be impactor-rich.
In order to resolve this mismatch, recently, a scenario to form the Moon from the magma ocean on the proto-Earth is suggested.
According to the scenario, the majority of heating occurs in the magma ocean on the proto-Earth, which results in the ejection of the target-originated materials.
In order to check whether this scenario is favourable to explain the origin of the Moon, we have carried out a parameter survey of the scenario.
As a result, we found that the canonical GIs can form the target-rich debris disc and concluded that the canonical GIs would form the Moon.