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Planet のバックアップ(No.54)


惑星セミナー2018

惑星セミナーは原則として毎週木曜日の14:00から理論部セミナー室で開催しています。
astro-phセミナーは毎週金曜日の12:30から理論部セミナー室で開催しています。

Schedule & History

2017年度 2016年度 2015年度 2014年度

日程発表タイトルRemarks
前期 第1回 5/17 15:00-荻原 正博Formation of the terrestrial planets in the solar system around 1 au via radial concentration of planetesimals15:00
前期 第2回 5/24 15:00-波々伯部 広隆Determination of outer edge of circumplanetary disk in local 3d hydrodynamic simulations15:00
前期 第3回 5/30 14:00-Dimitri VerasThe growing field of post-main-sequence exoplanetary science, with strong connections to the solar systemWednesday@Rinko room
前期 第4回 6/14 14:00-細野 七月Numerical simulations of the giant impact onto the magma ocean
前期 第5回 6/28 14:00-兵頭 龍樹On the origin of Phobos and Deimos
前期 第6回 7/12 14:00-樋口 有理可Inner solar system objects with hyperbolic orbits: Interstellar origin or Oort cloud comets?
前期 第7回 7/19 14:00-中野 龍之介中心星質量による原始惑星系円盤進化の変化
前期 第8回 7/26 14:00-中嶋 彩乃Orbital evolution of Saturn's mid-sized moons and the tidal heating of Enceladus
後期 第1回 9/19 14:00-波々伯部 広隆論文紹介 (Tanigawa et al. 2012, ApJ, Distribution of Accreting Gas and Angular Momentum onto Circumplanetary Disks)
後期 第2回 10/3 14:00-小久保 英一郎Planetesimal Formation by Gravitational Instability of a Porous Dust Disk
後期 第3回 10/24 14:00-瀧 哲朗Chondrule Survivability in the Protosolar disk
後期 第4回 10/31 13:00-Jason Man Yin WooThe curious case of Mars' formation13:00
後期 第5回 11/7 14:00-松本侑士TBA
後期 第6回 11/21 14:00-藤井悠里On the radiation hydrodynamic simulations of formation of circumplanetary disks
5/30 Dimitri Veras, The growing field of post-main-sequence exoplanetary science, with strong connections to the solar system
The quest for identifying the bulk chemical composition of extrasolar planets and robust observational evidence that between 25% and 50% of all Milky Way white dwarfs host currently dynamically-active planetary systems motivate investigations that link their formation and fate. Here I provide a review of our current knowledge of these systems, including an update on the observational and theoretical aspects of the groundbreaking discovery of at least one disintegrating minor planet transiting white dwarf WD 1145+017. I show how this field incorporates several facets of solar system physics and chemistry, and how its interdisciplinary nature requires input from orbital dynamics, stellar evolution, astrochemistry, atmospheric science and surface processes.
10/31 Jason Woo, The curious case of Mars' formation
Dynamical models of planet formation coupled with cosmochemical data from martian meteorites show that Mars' isotopic composition is distinct from that of Earth. Reconciliation of formation models with meteorite data require that Mars grew further from the Sun than its present position. Here, we evaluate this compositional difference in more detail by comparing output from two N-body planet formation models. The first of these planet formation models simulates what is termed the `Classical' case wherein Jupiter and Saturn are kept in their current orbits. We compare these results with another model based on the `Grand Tack', in which Jupiter and Saturn migrate through the primordial asteroid belt. Our estimate of the average fraction of chondrite assembled into Earth and Mars assumes that the initial solid disk consists of only sources of enstatite chondrite composition in the inner region, and ordinary chondrite in the outer region. Results of these analyses show that both models tend to yield Earth and Mars analogues whose accretion zones overlap. The Classical case fares better in forming Mars with its documented composition (29% to 68% enstatite chondrite plus 32% to 67% ordinary chondrite) though the Mars analogues are generally too massive. We also further calculate the isotopic composition of 17O, 50Ti, 54Cr, 142Nd, 64Ni, and 92Mo in the martian mantle from the Grand Tack simulations. We find that it is possible to match the calculated isotopic composition of all the above elements in Mars' mantle with their measured values, but the resulting uncertainties are too large to place good restriction on the early dynamical evolution and birth place of Mars.