中文版 | English

在结果中检索

GSTDTAP

浏览/检索结果: 共122条，第1-10条 帮助

限定条件    
已选(0)清除 条数/页：   排序方式：
A remnant planetary core in the hot-Neptune desert 期刊论文
NATURE, 2020, 583 (7814) : 39-+
作者:  David J. Armstrong;  Thé;  o A. Lopez;  Vardan Adibekyan;  Richard A. Booth;  Edward M. Bryant;  Karen A. Collins;  Magali Deleuil;  Alexandre Emsenhuber;  Chelsea X. Huang;  George W. King;  Jorge Lillo-Box;  Jack J. Lissauer;  Elisabeth Matthews;  Olivier Mousis;  Louise D. Nielsen;  Hugh Osborn;  Jon Otegi;  Nuno C. Santos;  Sé;  rgio G. Sousa;  Keivan G. Stassun;  Dimitri Veras;  Carl Ziegler;  Jack S. Acton;  Jose M. Almenara;  David R. Anderson;  David Barrado;  Susana C. C. Barros;  Daniel Bayliss;  Claudia Belardi;  Francois Bouchy;  Cé;  sar Briceñ;  o;  Matteo Brogi;  David J. A. Brown;  Matthew R. Burleigh;  Sarah L. Casewell;  Alexander Chaushev;  David R. Ciardi;  Kevin I. Collins;  Knicole D. Coló;  n;  Benjamin F. Cooke;  Ian J. M. Crossfield;  Rodrigo F. Dí;  az;  Elisa Delgado Mena;  Olivier D. S. Demangeon;  Caroline Dorn;  Xavier Dumusque;  Philipp Eigmü;  ller;  Michael Fausnaugh;  Pedro Figueira;  Tianjun Gan;  Siddharth Gandhi;  Samuel Gill;  Erica J. Gonzales;  Michael R. Goad;  Maximilian N. Gü;  nther;  Ravit Helled;  Saeed Hojjatpanah;  Steve B. Howell;  James Jackman;  James S. Jenkins;  Jon M. Jenkins;  Eric L. N. Jensen;  Grant M. Kennedy;  David W. Latham;  Nicholas Law;  Monika Lendl;  Michael Lozovsky;  Andrew W. Mann;  Maximiliano Moyano;  James McCormac;  Farzana Meru;  Christoph Mordasini;  Ares Osborn;  Don Pollacco;  Didier Queloz;  Liam Raynard;  George R. Ricker;  Pamela Rowden;  Alexandre Santerne;  Joshua E. Schlieder;  Sara Seager;  Lizhou Sha;  Thiam-Guan Tan;  Rosanna H. Tilbrook;  Eric Ting;  Sté;  phane Udry;  Roland Vanderspek;  Christopher A. Watson;  Richard G. West;  Paul A. Wilson;  Joshua N. Winn;  Peter Wheatley;  Jesus Noel Villasenor;  Jose I. Vines;  Zhuchang Zhan
收藏  |  浏览/下载：17/0  |  提交时间：2020/07/06

The interiors of giant planets remain poorly understood. Even for the planets in the Solar System, difficulties in observation lead to large uncertainties in the properties of planetary cores. Exoplanets that have undergone rare evolutionary processes provide a route to understanding planetary interiors. Planets found in and near the typically barren hot-Neptune '  desert'  (1,2)(a region in mass-radius space that contains few planets) have proved to be particularly valuable in this regard. These planets include HD149026b(3), which is thought to have an unusually massive core, and recent discoveries such as LTT9779b(4)and NGTS-4b(5), on which photoevaporation has removed a substantial part of their outer atmospheres. Here we report observations of the planet TOI-849b, which has a radius smaller than Neptune'  s but an anomalously large mass of39.1-2.6+2.7Earth masses and a density of5.2-0.8+0.7grams per cubic centimetre, similar to Earth'  s. Interior-structure models suggest that any gaseous envelope of pure hydrogen and helium consists of no more than3.9-0.9+0.8 per cent of the total planetary mass. The planet could have been a gas giant before undergoing extreme mass loss via thermal self-disruption or giant planet collisions, or it could have avoided substantial gas accretion, perhaps through gap opening or late formation(6). Although photoevaporation rates cannot account for the mass loss required to reduce a Jupiter-like gas giant, they can remove a small (a few Earth masses) hydrogen and helium envelope on timescales of several billion years, implying that any remaining atmosphere on TOI-849b is likely to be enriched by water or other volatiles from the planetary interior. We conclude that TOI-849b is the remnant core of a giant planet.


Observations of TOI-849b reveal a radius smaller than Neptune'  s but a large mass of about 40 Earth masses, indicating that the planet is the remnant core of a gas giant.


  
Deep rotating convection generates the polar hexagon on Saturn 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2020, 117 (25) : 13991-13996
作者:  Yadav, Rakesh K.;  Bloxham, Jeremy
收藏  |  浏览/下载：5/0  |  提交时间：2020/06/16
planetary atmospheres  rotating convection  turbulence  
Juno In Situ Observations Above the Jovian Equatorial Ionosphere 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (12)
作者:  Valek, P. W.;  Bagenal, F.;  Ebert, R. W.;  Allegrini, F.;  McComas, D. J.;  Szalay, J. R.;  Wilson, R. J.;  Bolton, S. J.;  Connerney, J. E. P.
收藏  |  浏览/下载：16/0  |  提交时间：2020/05/25
Propagation Teepee: A Possible High-Frequency (15-30 MHz) Remote Lightning Signature Identified by Citizen Scientists 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (11)
作者:  Fung, Shing F.;  Typinski, David;  Flagg, Richard;  Ashcraft, Thomas;  Greenman, Wes;  Higgins, Charles;  Brown, James;  Dodd, Larry;  Reyes, Francisco;  Sky, Jim;  Thieman, James;  Garcia, Leonard
收藏  |  浏览/下载：8/0  |  提交时间：2020/05/13
radio wave propagation  lightning  ionospheric physics  space weather  citizen science  
Favorable Conditions for Magnetic Reconnection at Ganymede's Upstream Magnetopause 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (6)
作者:  Kaweeyanun, N.;  Masters, A.;  Jia, X.
收藏  |  浏览/下载：11/0  |  提交时间：2020/07/02
Ganymede  magnetic reconnection  magnetopause  modeling  
Jupiter's Gravity Field Halfway Through the Juno Mission 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (4)
作者:  Durante, D.;  Parise, M.;  Serra, D.;  Zannoni, M.;  Notaro, V;  Racioppa, P.;  Buccino, D. R.;  Lari, G.;  Casajus, L. Gomez;  Iess, L.;  Folkner, W. M.;  Tommei, G.;  Tortora, P.;  Bolton, S. J.
收藏  |  浏览/下载：7/0  |  提交时间：2020/07/02
Alfvenic Acceleration Sustains Ganymede's Footprint Tail Aurora 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (3)
作者:  Szalay, J. R.;  Allegrini, F.;  Bagenal, F.;  Bolton, S. J.;  Bonfond, B.;  Clark, G.;  Connerney, J. E. P.;  Ebert, R. W.;  Gershman, D. J.;  Giles, R. S.;  Gladstone, G. R.;  Greathouse, T.;  Hospodarsky, G. B.;  Imai, M.;  Kurth, W. S.;  Kotsiaros, S.;  Louarn, P.;  McComas, D. J.;  Saur, J.;  Sulaiman, A. H.;  Wilson, R. J.
收藏  |  浏览/下载：10/0  |  提交时间：2020/07/02
Io's Effect on Energetic Charged Particles as Seen in Juno Data 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2019, 46 (23) : 13615-13620
作者:  Paranicas, C.;  Mauk, B. H.;  Haggerty, D. K.;  Clark, G.;  Kollmann, P.;  Rymer, A. M.;  Westlake, J.;  Allen, R. C.;  Szalay, J.;  Ebert, R. W.;  Sulaiman, A. H.;  Imai, M.;  Roussos, E.;  Krupp, N.;  Nenon, Q.;  Bagenal, F.;  Bolton, S. J.
收藏  |  浏览/下载：11/0  |  提交时间：2020/02/17
energetic charged particles  Io  Juno  
Energetic Oxygen and Sulfur Charge States in the Outer Jovian Magnetosphere: Insights From the Cassini Jupiter Flyby 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2019, 46 (21) : 11709-11717
作者:  Allen, R. C.;  Paranicas, C. P.;  Bagenal, F.;  Vines, S. K.;  Hamilton, D. C.;  Allegrini, F.;  Clark, G.;  Delamere, P. A.;  Kim, T. K.;  Krimigis, S. M.;  Mitchell, D. G.;  Smith, T. H.;  Wilson, R. J.
收藏  |  浏览/下载：10/0  |  提交时间：2020/02/17
Jupiter  Composition  Cassini  Juno  
On the Relation Between Jovian Aurorae and the Loading/Unloading of the Magnetic Flux: Simultaneous Measurements From Juno, Hubble Space Telescope, and Hisaki 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2019, 46 (21) : 11632-11641
作者:  Yao, Z. H.;  Grodent, D.;  Kurth, W. S.;  Clark, G.;  Mauk, B. H.;  Kimura, T.;  Bonfond, B.;  Ye, S-Y;  Lui, A. T.;  Radioti, A.;  Palmaerts, B.;  Dunn, W. R.;  Ray, L. C.;  Bagenal, F.;  Badman, S., V;  Rae, I. J.;  Guo, R. L.;  Pu, Z. Y.;  Gerard, J-C;  Yoshioka, K.;  Nichols, J. D.;  Bolton, S. J.;  Levin, S. M.
收藏  |  浏览/下载：15/0  |  提交时间：2020/02/17