An Earth-sized exoplanet with a Mercury-like composition
An Earth-sized exoplanet with a Mercury-like composition
复制标题
一颗地球大小的系外行星，其成分与水星类似
作者：
A. Santerne;B. Brugger;David J Armstrong;V. Adibekyan;J. Lillo;H. Gosselin;A. Aguichine;J. Almenara;D. Barrado;S. Barros;D. Bayliss;I. Boisse;A. Bonomo;F. Bouchy;D. Brown;M. Deleuil;E. Delgado Mena;O. Demangeon;R. Díaz;A. Doyle;X. Dumusque;F. Faedi;J. Faria;P. Figueira;E. Foxell;H. Giles;G. Hébrard;S. Hojjatpanah;M. Hobson;J. Jackman;G. King;J. Kirk;K. Lam;R. Ligi;C. Lovis;T. Louden;J. McCormac;O. Mousis;J. Neal;H. Osborn;F. Pepe;D. Pollacco;N. Santos;S. Sousa;S. Udry;A. Vigan
地球、金星、火星和一些太阳系外类地行星1的质量和半径与约30%金属核心和70%硅酸盐地幔2的质量分数一致。在太阳系的内部边界，水星的成分完全不同，其质量分数约为 70% 金属核和 30% 硅酸盐地幔3。人们提出了几种形成或演化情景来解释这种富含金属的成分，例如巨大的撞击4、地幔蒸发5或原行星盘内边缘硅酸盐的消耗6。这些情景仍然存在激烈争论。在这里，我们报告发现了一个多重凌日行星系统（K2-229），其中内行星的半径为1.165±0.066地球半径，质量为2.59±0.43地球质量。因此，这颗地球大小的行星的核心质量分数与水星的核心质量分数一致，尽管根据主星化学，预计它与地球的核心质量分数相似7。这个更大的水星类似物要么是由非常奇特的成分形成的，要么是通过失去部分地幔等而进化而来的。对 K2-229 b 等类水星系外行星的进一步表征将有助于将对水星的详细现场观测（包括 MESSENGER 和 BepiColombo8）纳入太阳和太阳系外类地行星形成和演化的全球背景中。水星内部丰富的金属含量在太阳系的岩石行星中是独一无二的。本文提出的“超级水星”系外行星的特征将提高我们对类水星行星如何形成和演化的理解。
Earth, Venus, Mars and some extrasolar terrestrial planets1 have a mass and radius that is consistent with a mass fraction of about 30% metallic core and 70% silicate mantle2. At the inner frontier of the Solar System, Mercury has a completely different composition, with a mass fraction of about 70% metallic core and 30% silicate mantle3. Several formation or evolution scenarios are proposed to explain this metal-rich composition, such as a giant impact4, mantle evaporation5 or the depletion of silicate at the inner edge of the protoplanetary disk6. These scenarios are still strongly debated. Here, we report the discovery of a multiple transiting planetary system (K2-229) in which the inner planet has a radius of 1.165 ± 0.066 Earth radii and a mass of 2.59 ± 0.43 Earth masses. This Earth-sized planet thus has a core-mass fraction that is compatible with that of Mercury, although it was expected to be similar to that of Earth based on host-star chemistry7. This larger Mercury analogue either formed with a very peculiar composition or has evolved, for example, by losing part of its mantle. Further characterization of Mercury-like exoplanets such as K2-229 b will help to put the detailed in situ observations of Mercury (with MESSENGER and BepiColombo8) into the global context of the formation and evolution of solar and extrasolar terrestrial planets. The abundance of metals in Mercury’s interior is unique among the rocky planets of the Solar System. The characterization of the ‘super-Mercury’ exoplanet presented in this paper will improve our understanding of how Mercury-like planets can form and evolve.
DOI：
10.1088/0004-637x/800/2/135
发表时间：
2014-12
期刊：
The Astrophysical Journal
影响因子：
--
作者：
C. Dressing;D. Charbonneau;X. Dumusque;S. Gettel;F. Pepe;A. Collier Cameron;D. Latham;E. Molinari;S. Udry;L. Affer;A. Bonomo;L. Buchhave;R. Cosentino;P. Figueira;A. Fiorenzano;A. Harutyunyan;R. Haywood;J. Johnson;M. López-Morales;C. Lovis;L. Malavolta;M. Mayor;G. Micela;F. Motalebi;V. Nascimbeni;D. Phillips;G. Piotto;D. Pollacco;D. Queloz;K. Rice;D. Sasselov;D. Ségransan;A. Sozzetti;A. Szentgyorgyi;C. Watson
通讯作者：
C. Dressing;D. Charbonneau;X. Dumusque;S. Gettel;F. Pepe;A. Collier Cameron;D. Latham;E. Molinari;S. Udry;L. Affer;A. Bonomo;L. Buchhave;R. Cosentino;P. Figueira;A. Fiorenzano;A. Harutyunyan;R. Haywood;J. Johnson;M. López-Morales;C. Lovis;L. Malavolta;M. Mayor;G. Micela;F. Motalebi;V. Nascimbeni;D. Phillips;G. Piotto;D. Pollacco;D. Queloz;K. Rice;D. Sasselov;D. Ségransan;A. Sozzetti;A. Szentgyorgyi;C. Watson
影响因子：
6.5
作者：
E. Guenther;O. Barragán;F. Dai;Davide Gandolfi;T. Hirano;M. Fridlund;M. Fridlund;M. Fridlund;L. Fossati;A. Chau;R. Helled;J. Korth;J. Prieto-Arranz;J. Prieto-Arranz;D. Nespral;D. Nespral;G. Antoniciello;H. Deeg;H. Deeg;M. Hjorth;S. Grziwa;S. Albrecht;A. Hatzes;H. Rauer;H. Rauer;S. Csizmadia;Alexis M. S. Smith;J. Cabrera;N. Narita;P. Arriagada;J. Burt;R. P. Butler;W. Cochran;J. Crane;P. Eigmueller;A. Erikson;J. Johnson;A. Kiilerich;D. Kubyshkina;E. Pallé;E. Pallé;C. M. Persson;M. Pätzold;S. Sabotta;B. Sato;S. Shectman;J. Teske;I. Thompson;V. V. Eylen-V.;G. Nowak;G. Nowak;A. Vanderburg;J. Winn;R. Wittenmyer
通讯作者：
E. Guenther;O. Barragán;F. Dai;Davide Gandolfi;T. Hirano;M. Fridlund;M. Fridlund;M. Fridlund;L. Fossati;A. Chau;R. Helled;J. Korth;J. Prieto-Arranz;J. Prieto-Arranz;D. Nespral;D. Nespral;G. Antoniciello;H. Deeg;H. Deeg;M. Hjorth;S. Grziwa;S. Albrecht;A. Hatzes;H. Rauer;H. Rauer;S. Csizmadia;Alexis M. S. Smith;J. Cabrera;N. Narita;P. Arriagada;J. Burt;R. P. Butler;W. Cochran;J. Crane;P. Eigmueller;A. Erikson;J. Johnson;A. Kiilerich;D. Kubyshkina;E. Pallé;E. Pallé;C. M. Persson;M. Pätzold;S. Sabotta;B. Sato;S. Shectman;J. Teske;I. Thompson;V. V. Eylen-V.;G. Nowak;G. Nowak;A. Vanderburg;J. Winn;R. Wittenmyer
EPIC 201702477b：一颗来自 K2 的过渡褐矮星，轨道运行 41 天
DOI：
10.3847/1538-3881/153/1/15
发表时间：
2016
期刊：
The Astronomical Journal
影响因子：
--
作者：
Bayliss D
通讯作者：
Bayliss D