A basin-free spherical shape as an outcome of a giant impact on asteroid Hygiea

被引:36
作者
Vernazza, P. [1 ]
Jorda, L. [1 ]
Sevecek, P. [2 ]
Broz, M. [2 ]
Viikinkoski, M. [3 ]
Hanus, J. [2 ]
Carry, B. [4 ]
Drouard, A. [1 ]
Ferrais, M. [5 ]
Marsset, M. [6 ]
Marchis, F. [1 ,7 ]
Birlan, M. [8 ]
Podlewska-Gaca, E. [9 ,10 ]
Jehin, E. [5 ]
Bartczak, P. [9 ]
Dudzinski, G. [9 ]
Berthier, J. [8 ]
Castillo-Rogez, J. [11 ]
Cipriani, F. [12 ]
Colas, F. [8 ]
DeMeo, F. [6 ]
Dumas, C. [13 ]
Durech, J. [2 ]
Fetick, R. [1 ,14 ]
Fusco, T. [1 ,14 ]
Grice, J. [4 ,15 ]
Kaasalainen, M. [3 ]
Kryszczynska, A. [9 ]
Lamy, P. [1 ]
Le Coroller, H. [1 ]
Marciniak, A. [9 ]
Michalowski, T. [9 ]
Michel, P. [4 ]
Rambaux, N. [8 ]
Santana-Ros, T. [16 ,17 ]
Tanga, P. [4 ]
Vachier, F. [8 ]
Vigan, A. [1 ]
Witasse, O. [12 ]
Yang, B. [18 ]
Gillon, M. [5 ]
Benkhaldoun, Z. [19 ]
Szakats, R. [20 ]
Hirsch, R. [9 ]
Duffard, R. [21 ]
Chapman, A. [22 ]
Maestre, J. L. [23 ]
机构
[1] Aix Marseille Univ, CNRS, UMR 7326, LAM Lab Astrophys Marseille, Marseille, France
[2] Charles Univ Prague, Inst Astron, Prague, Czech Republic
[3] Tampere Univ, Math & Stat, Tampere, Finland
[4] Univ Cote Azur, CNRS, Lab Lagrange, Observ Cote Azur, Nice, France
[5] Univ Liege, Space Sci Technol & Astrophys Res Inst, Liege, Belgium
[6] MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA USA
[7] SETI Inst, Carl Sagan Ctr, Mountain View, CA USA
[8] Observ Paris, IMCCE, Paris, France
[9] Adam Mickiewicz Univ, Astron Observ Inst, Fac Phys, Poznan, Poland
[10] Univ Szczecin, Inst Phys, Szczecin, Poland
[11] CALTECH, Jet Prop Lab, Pasadena, CA USA
[12] European Space Agcy, ESTEC Sci Support Off, Noordwijk, Netherlands
[13] TMT Observ, Pasadena, CA USA
[14] Off Natl Etud & Rech Aerosp, French Aerosp Lab, Chatillon, France
[15] Open Univ, Sch Phys Sci, Milton Keynes, Bucks, England
[16] Univ Alicante, Dept Fis Ingn Sistemas & Teoria Senal, Alicante, Spain
[17] Univ Barcelona, Inst Ciencies Cosmos, Barcelona, Spain
[18] European Southern Observ, Santiago, Chile
[19] Cadi Ayyad Univ, High Energy Phys & Astrophys Lab, Oukaimeden Observ, Marrakech, Morocco
[20] Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Budapest, Hungary
[21] Inst Astrofis Andalucia CSIC, Glorieta Astron, Granada, Spain
[22] Observ Buenos Aires, Buenos Aires, DF, Argentina
[23] Observ Albox, Albox, Spain
关键词
4; VESTA; SIMULATIONS; FLUIDIZATION; FAMILIES; FRACTURE; CERES;
D O I
10.1038/s41550-019-0915-8
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
(10) Hygiea is the fourth largest main belt asteroid and the only known asteroid whose surface composition appears similar to that of the dwarf planet (1) Ceres(1,2), suggesting a similar origin for these two objects. Hygiea suffered a giant impact more than 2 Gyr ago(3) that is at the origin of one of the largest asteroid families. However, Hygeia has never been observed with sufficiently high resolution to resolve the details of its surface or to constrain its size and shape. Here, we report high-angular-resolution imaging observations of Hygiea with the VLT/SPHERE instrument (20 mas at 600 nm) that reveal a basin-free nearly spherical shape with a volume-equivalent radius of 217 +/- 7 km, implying a density of 1,944 +/- 250 kg m(-3) to 1 sigma. In addition, we have determined a new rotation period for Hygiea of 13.8 h, which is half the currently accepted value. Numerical simulations of the family-forming event show that Hygiea's spherical shape and family can be explained by a collision with a large projectile (diameter 75-150 km). By comparing Hygiea's sphericity with that of other Solar System objects, it appears that Hygiea is nearly as spherical as Ceres, opening up the possibility for this object to be reclassified as a dwarf planet.
引用
收藏
页码:136 / 141
页数:6
相关论文
共 51 条
[21]   Impact crater collapse [J].
Melosh, HJ ;
Ivanov, BA .
ANNUAL REVIEW OF EARTH AND PLANETARY SCIENCES, 1999, 27 :385-415
[22]  
MICHALOWSKI T, 1991, ASTRON ASTROPHYS SUP, V91, P53
[23]   Collisions and gravitational reaccumulation: Forming asteroid families and satellites [J].
Michel, P ;
Benz, W ;
Tanga, P ;
Richardson, DC .
SCIENCE, 2001, 294 (5547) :1696-1700
[24]  
Mises RV., 1913, NACHRICHTEN GESELLSC, V1913, P582, DOI DOI 10.1016/J.ENGFRACMECH.2016.08.011
[25]  
Nesvorny D., 2015, Asteroids IV, P297, DOI [10.2458/azuuapress9780816532131-ch016, DOI 10.2458/AZUUAPRESS9780816532131-CH016]
[26]   NEOWISE REACTIVATION MISSION YEAR ONE: PRELIMINARY ASTEROID DIAMETERS AND ALBEDOS [J].
Nugent, C. R. ;
Mainzer, A. ;
Masiero, J. ;
Bauer, J. ;
Cutri, R. M. ;
Grav, T. ;
Kramer, E. ;
Sonnett, S. ;
Stevenson, R. ;
Wright, E. L. .
ASTROPHYSICAL JOURNAL, 2015, 814 (02)
[27]  
Ostro S. J, 2000, ASTEROID RADAR SHAPE
[28]   High-resolution shape model of Ceres from stereophotoclinometry using Dawn Imaging Data [J].
Park, R. S. ;
Vaughan, A. T. ;
Konopliv, A. S. ;
Ermakov, A., I ;
Mastrodemos, N. ;
Castillo-Rogez, J. C. ;
Joy, S. P. ;
Nathues, A. ;
Polanskey, C. A. ;
Rayman, M. D. ;
Riedel, J. E. ;
Raymond, C. A. ;
Russell, C. T. ;
Zuber, M. T. .
ICARUS, 2019, 319 :812-827
[29]   MAGELLAN - RADAR PERFORMANCE AND DATA PRODUCTS [J].
PETTENGILL, GH ;
FORD, PG ;
JOHNSON, WTK ;
RANEY, RK ;
SODERBLOM, LA .
SCIENCE, 1991, 252 (5003) :260-265
[30]  
Preusker F, 2014, P 9 C EUR PLAN SCI C, V9