Understanding the evolution of asteroidal surfaces caused by impacts using numerical simulation for granular particles.

• Project/Area Number: 24540459
• 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: Chiba Institute of Technology
• Principal Investigator: WADA Koji 千葉工業大学, 惑星探査研究センター, 上席研究員 (10396856)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥5,070,000 (Direct Cost: ¥3,900,000、Indirect Cost: ¥1,170,000); Fiscal Year 2014: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2013: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2012: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000)
• Keywords: 天体衝突 / 数値シミュレーション / 粉体 / 小惑星

Outline of Final Research Achievements

The surfaces of asteroids and planetesimals are highly porous granular layers under small gravity. We conducted numerical simulations of impacts onto such layers using a numerical code, so-called Distinct Element Method in order to evaluate influences of celestial body impacts on the evolution of asteroids and planetesimals. Our results show that a projectile in penetrating granular layer is affected by a drag force consisting of an inertia term and a viscous term and that the total amount of ejecta mass at impact is proportional to the projectile momentum. These results allow us to quantitatively discuss on the evolution of asteroidal surfaces which is determined by the balance between addition and erosion of impact bodies.

Research Products

• [Journal Article] Crater-Ray Formation by Impact-Induced Ejecta Particles (2015)
  • Author(s): T. Kadono, A. I. Suzuki, K. Wada, N. K. Mitani, S. Yamamoto, M. Arakawa, S. Sugita, J. Haruyama, and A. M. Nakamura
  • Journal Title: Icarus Volume: 250 Pages: 215-221
  • DOI: 10.1016/j.icarus.2014.11.030
  • Peer Reviewed
• [Journal Article] Numerical Simulations of Impacts of a spherical Shell Projectile on Small Asteroids (2015)
  • Author(s): Kurosawa, K., Senshu, H., Wada, K., and TDSS team
  • Journal Title: Proc. Lunar Planet. Sci. Conf. 46th Volume: 1 Pages: 1868-1868
  • Open Access
• [Journal Article] Electrostatic lofting of dust aggregates near the terminator of airless bodies and its implication for the formation of exozodiacal disks (2014)
  • Author(s): Kimura, H., Senshu, H., and Wada, K.
  • Journal Title: Planetary and Space Science Volume: 未定 Pages: 64-72
  • DOI: 10.1016/j.pss.2014.03.017
  • Peer Reviewed
• [Journal Article] An Examination of Collisional Growth of Silicate Dust in Protoplanetary Disks (2014)
  • Author(s): Yamamoto, T., Kadono,T. and Wada, K.
  • Journal Title: The Astrophysical Journal Letters Volume: 783 Issue: 2 Pages: L36-L36
  • DOI: 10.1088/2041-8205/783/2/l36
  • Peer Reviewed
• [Journal Article] Large Scale Impact Experiments Simulating Small Carry-On Impactor (SCI) Equipped on Hayabusa-2 (2014)
  • Author(s): Wada, K., Arakawa, M., Saiki, T., Imamura, H., Hayakawa, M., Okamoto, C., Shirai, K., Takagi, Y., Kadono, T., Tsuda, Y., Yano, H., Nakazawa, S., Hirata, N., Ogawa, K., Iijima, Y., Michel, P., and Jutzi, M.
  • Journal Title: Proc. Lunar Planet. Sci. Conf. Volume: 45
• [Journal Article] Growth efficiency of dust aggregates through collisions with high mass ratios (2013)
  • Author(s): Wada, K., Tanaka, H., Okuzumi, S., Kobayashi, H., Suyama, T., Kimura, H., and Yamamoto, T.
  • Journal Title: Astronomy & Astrophysics Volume: 559 Pages: A62-A62
  • DOI: 10.1051/0004-6361/201322259
  • Peer Reviewed
• [Journal Article] Fluffy dust forms icy planetesimals by static compression (2013)
  • Author(s): A. Kataoka, H. Tanaka, S. Okuzumi, and K. Wada
  • Journal Title: Astronomy & Astrophysics Volume: 557 Pages: L4-L4
  • DOI: 10.1051/0004-6361/201322151
  • Peer Reviewed
• [Journal Article] Static compression of porous dust aggregates (2013)
  • Author(s): Akimasa Kataoka
  • Journal Title: Astronomy & Astrophysics Volume: (印刷中)(oin press)(未定) Pages: A4-A4
  • DOI: 10.1051/0004-6361/201321325
  • Peer Reviewed
• [Journal Article] A formation mechanism for concentric ridges in ejecta surrounding impact craters in a layer of fine glass beads (2013)
  • Author(s): Suzuki, A. I., Nakamura, A. M., Kadono, T., Wada, K., Yamamoto, S., & Arakawa, M.
  • Journal Title: Icarus Volume: 225 Issue: 1 Pages: 298-307
  • DOI: 10.1016/j.icarus.2013.03.027
  • Peer Reviewed
• [Journal Article] はやぶさ2 SCI/DCAM3 チーム，2013, 火の鳥「はやぶさ」未来編その 3 ～SCI/DCAM3と衝突の科学～, (2013)
  • Author(s): 荒川政彦，和田浩二
  • Journal Title: 日本惑星科学会誌（遊・星・人） Volume: Vo. 22, No.3 Pages: 152-158
• [Journal Article] PENETRATION PROCESS IN GRANULAR MEDIA REVEALED BY NUMERICAL SIMULATION. (2013)
  • Author(s): Wada, K., and Nakamura, A. M.
  • Journal Title: Proc. Lunar Planet. Sci. Conf. Volume: 44 Pages: 1466-1466
• [Journal Article] SMALL CARRY-ON IMPACTOR (SCI): ITS SCIENTIFIC PURPOSE, OPERATION, AND OBSERVATION PLAN IN HAYABYSA-2 MISSION (2013)
  • Author(s): Arakawa, M., Saiki, T., Wada, K., et al.
  • Journal Title: Proc. Lunar Planet. Sci. Conf. Volume: 44 Pages: 1904-1904
• [Journal Article] Impact and intrusion experiments on the deceleration of low-velocity impactors by small-body regolith (2012)
  • Author(s): Nakamura, A. M., Setoh, M.,Wada, K., Yamashita, Y., and Sangen, K.
  • Journal Title: Icarus Volume: 223 Pages: 222-233
  • Peer Reviewed
• [Journal Article] Geometrical cross sections of dust aggregates and a compression model for aggregate collisions (2012)
  • Author(s): Suyama, T., Wada, K., Tanaka, H., and Okuzumi, S.
  • Journal Title: Astrophys. J. Volume: 753
  • Peer Reviewed
• [Journal Article] Rapid coagulation of porous dust aggregates outside the snow line: A pathway to successful icy planetesimal formation (2012)
  • Author(s): Okuzumi, S., Tanaka, H., Kobayashi, H., and Wada, K.
  • Journal Title: Astrophys. J. Volume: 752
  • Peer Reviewed
• [Journal Article] Growth of cosmic dust aggregates and reexamination of particle interaction models. (2012)
  • Author(s): Tanaka, H., Wada, K., Suyama, T., and Okuzumi, S.
  • Journal Title: Prog. Theor. Phys. Suppl. Volume: 195 Pages: 101-113
  • NAID: 110009488986
  • Peer Reviewed
• [Presentation] Hayabusa2 deployable camera 3 (DCAM3) for impact experiment on asteroid: scientific observation plan and instrument performance (2015)
  • Author(s): Ogawa, K., M. Arakawa, M., K. Wada, K. Shirai, H. Sawada, R. Honda, K. Ishibashi, T. Kadono, N. Sakatani, S. Nakazawa, H. Hayakawa
  • Organizer: 46th Lunar Planet. Sci. Conf.
  • Place of Presentation: The Woodlands, Texas, USA
  • Year and Date: 2015-03-19
• [Presentation] Numerical Simulations of Impacts of a spherical Shell Projectile on Small Asteroids (2015)
  • Author(s): Kurosawa, K., H. Senshu, K. Wada, and TDSS team
  • Organizer: 46th Lunar Planet. Sci. Conf.
  • Place of Presentation: The Woodlands, Texas, USA
  • Year and Date: 2015-03-17
• [Presentation] How to detect a small crater produced by Small Carry-on Impactor (SCI) using Thermal InfraRed Camera (TIR) (2015)
  • Author(s): Wada, K.
  • Organizer: The 4th HJST meeting
  • Place of Presentation: JAXA （神奈川県相模原市）
  • Year and Date: 2015-02-24
• [Presentation] モノマーサイズ分布をもつダストの衝突：ダストサイズの影響 (2015)
  • Author(s): 和田浩二
  • Organizer: 新学術領域「系外惑星」B01, B02 班研究会「円盤から惑星・衛星へ：形成と進化」
  • Place of Presentation: 東京工業大学（東京都目黒区）
  • Year and Date: 2015-02-16
• [Presentation] Small Carry-On Impactor (SCI) and Deployable Camera 3 (DCAM3) in Hayabusa-2 Mission. (2014)
  • Author(s): Arakawa, M., T. Saiki, K. Wada, T. Kadono, Y. Takagi, K. Shirai, C. Okamoto, H. Yano, M. Hayakawa, S. Nakazawa, N. Hirata, M. Kobayashi, P. Michel, M. Jutzi, H. Imamura, K. Ogawa, Y. Iijima, R. Honda, K. Ishibashi, N. Sakatani, H. Hayakawa, H. Sawada
  • Organizer: AIDA international workshop
  • Place of Presentation: JHUAPL, MD, USA
  • Year and Date: 2014-10-16
• [Presentation] 小惑星における「衝突」を見る (2014)
  • Author(s): 和田浩二
  • Organizer: 赤外線観測と惑星科学
  • Place of Presentation: 惑星科学研究センター（CPS）（兵庫県神戸市）
  • Year and Date: 2014-10-09
• [Presentation] モノマーサイズ分布のあるダストアグリゲイトの衝突とイジェクタ量 (2014)
  • Author(s): 和田浩二，田中秀和，小林浩，奥住聡，木村宏
  • Organizer: 日本惑星科学会2014 年秋季講演会
  • Place of Presentation: 東北大学片平キャンパスさくらホール（宮城県仙台市）
  • Year and Date: 2014-09-24 – 2014-09-26
• [Presentation] Numerical simulation of various types of dust aggregate collisions. (2014)
  • Author(s): Wada, K.
  • Organizer: The influence of material and temperature on the dust coagulation in protoplanetary disks
  • Place of Presentation: 北海道大学（北海道札幌市）
  • Year and Date: 2014-08-06
• [Presentation] Ejecta Mass at Collisions of Dust Aggregates (2014)
  • Author(s): Wada, K., H. Tanaka, H. Kobayashi, S. Okuzumi
  • Organizer: 第7回Cosmic Dust研究会
  • Place of Presentation: 大阪産業大学梅田サテライトキャンパス（大阪府大阪市）
  • Year and Date: 2014-08-04 – 2014-08-08
• [Presentation] はやぶさ２小型搭載型衝突装置による科学 (2014)
  • Author(s): 和田浩二，SCI チーム，DCAM3 チーム
  • Organizer: 日本地球惑星科学連合2014 年大会
  • Place of Presentation: パシフィコ横浜（神奈川県横浜市）
  • Year and Date: 2014-04-28
  • Invited
• [Presentation] Large Scale Impact Experiments Simulating Small Carry-On Impactor (SCI) Equipped on Hayabusa-2 (2014)
  • Author(s): Wada, K., Arakawa, M., Saiki, T., Imamura, H., Hayakawa, M., Okamoto, C., Shirai, K., Takagi, Y., Kadono, T., Tsuda, Y., Yano, H., Nakazawa, S., Hirata, N., Ogawa, K., Iijima, Y., Michel, P., and Jutzi, M.
  • Organizer: Lunar Planet. Sci. Conf. 45th
  • Place of Presentation: Woodlands, TX, USA
• [Presentation] ダスト衝突時のイジェクタ量について (2014)
  • Author(s): 和田浩二，田中秀和，小林浩，奥住聡
  • Organizer: 新学術領域 B01 班研究会「原始惑星系円盤から惑星へ」
  • Place of Presentation: 神戸大学CPS, 兵庫県
• [Presentation] Amount of ejecta mass at dust aggregate collisions (2013)
  • Author(s): Wada, K., Tanaka, H., H. Kobayashi, and S. Okuzumi
  • Organizer: Exoplanets and Disks: Their formation and Diversity II, The 5nd Subaru International Conference
  • Place of Presentation: Keauhou Kona, Hawaii, USA
• [Presentation] イジェクタカーテン観測からイジェクタの放出角度と速さ を推定する方法 (2013)
  • Author(s): 和田浩二, 辻堂さやか, 荒川政彦
  • Organizer: 日本惑星科学会2013 年秋季講演会
  • Place of Presentation: 石垣市民会館，沖縄県
• [Presentation] 衝突実験と数値 計算におけるクレーターレイの形成 (2013)
  • Author(s): 門野敏彦，鈴木絢子，和田浩二，山本聡，荒川政彦，杉田精司，中村昭子
  • Organizer: 日本地球惑星科学連合2013 年大会
  • Place of Presentation: 幕張メッセ，千葉県
• [Presentation] Small Carry-on Impactor (SCI): Its scientific purpose, operation, and observation plan in Hayabusa-2 mission. (2013)
  • Author(s): Wada, K.
  • Organizer: Korea-Japan Joint Workshop on Solar System Research
  • Place of Presentation: Daejeon, Korea
• [Presentation] PENETRATION PROCESS IN GRANULAR MEDIA REVEALED BY NUMERICAL SIMULATION (2013)
  • Author(s): Wada, K., and Nakamura, A. M.
  • Organizer: Lunar Planet. Sci. Conf. 44th
  • Place of Presentation: Woodlands, TX, USA
• [Presentation] Collision simulation of dust aggregates with monomer size distributions (2013)
  • Author(s): Wada, K., Tanaka, H., Suyama, T., Kimura, H., and Yamamoto, T.
  • Organizer: Cosmic Dust
  • Place of Presentation: CPS, Kobe
• [Presentation] Penetration Resistance in Porous Granular Bodies: Results from Numerical Simulations (2013)
  • Author(s): Wada, K. and Nakamura, A. M.
  • Organizer: Asteroids, Comets, Meteor 2012
  • Place of Presentation: Toki Messe (Niigata Convention Center), Niigata, Japan