Please use this identifier to cite or link to this item: http://hdl.handle.net/20.500.12666/159
Title: A remnant planetary core in the hot-Neptune desert
Authors: Armstrong, D. J.
López, T. A.
Adibekyan, V.
Booth, R. A.
Bryant, E. M.
Collins, K. A.
Deleuil, M.
Emsenhuber, A.
Huang, C. X.
King, G. W.
Lillo Box, J.
Lissauer, J. J.
Matthews, E.
Mousis, O.
Nielsen, L. D.
Osborn, H.
Otegi, J.
Santos, N. C.
Sousa, S. G.
Stassun, K. G.
Veras, D.
Ziegler, C.
Acton, J. S.
Almenara, J. M.
Anderson, D. R.
Barrado, D.
Barros, S. C. C.
Bayliss, D.
Belardi, C.
Bouchy, F.
Briceño, C.
Brogi, M.
Brown, D. J. A.
Burleigh, M. R.
Casewell, S. L.
Chausev, A.
Ciardi, D. R.
Collins, K. I.
Colón, K. D.
Cooke, B. F.
Crossfield, J. M.
Díaz, R. F.
Delgado Mena, E.
Gandhi, O. D. S.
Gill, Samuel
Gonzales, E. J.
Goad, M. R.
Günther, M. N.
Helled, R.
Hojjatpanah, S.
Howell, Steve B.
Jackman, J.
Jenkins, J. S.
Jenkins, J. M.
Jensen, E. L. N.
Kennedy, G. M.
Latham, D. W.
Law, N.
Osborn, M.
Pollacco, D.
Queloz, D.
Raynard, L.
Ricker, G. R.
Rowden, P.
Santerne, A.
Schlieder, J. E.
Seager, S.
Sha, L.
Tan, T. G.
Tilbrook, R. H.
Ting, E.
Udry, S.
Vanderspek, R.
Watson, C. A.
West, R. G.
Wilson, P. A.
Winn, J. N.
Wheatley, P.
Villaseñor, J. N.
Vines, J. I.
Zhan, Z.
Keywords: Planetary Core;Neptune;Desert;TOI-849b
Issue Date: 1-Jul-2020
Publisher: Springer Nature Research Journals
DOI: 10.1038/s41586-020-2421-7
Published version: https://www.nature.com/articles/s41586-020-2421-7
Citation: Nature 583: 39- 42(2020)
Abstract: 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.
Description: This paper includes data collected by the TESS missions, which are publicly available from MAST. Funding for the TESS mission is provided by NASA’s Science Mission directorate. We acknowledge the use of public TESS Alert data from pipelines at the TESS Science Office and at the TESS Science Processing Operations Center. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center for the production of the SPOC data products. This research made use of the Exoplanet Follow-up Observation Program website and the NASA Exoplanet Archive, which are operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. This work makes use of observations from the LCOGT network and is based in part on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programme IDs 1102.C-0249 and P103.C-0449. Some of the observations presented in the paper used the High-Resolution Imaging instrument Zorro at Gemini South (programme ID GS-2019B-Q-111). Zorro was funded by the NASA Exoplanet Exploration Program and built at the NASA Ames Research Center by S.B.H., N. Scott, E. P. Horch and E. Quigley. D.J.A., D.V. and S.L.C. acknowledge support from the STFC via Ernest Rutherford Fellowships ST/R00384X/1, ST/P003850/1 and ST/R003726/1, respectively. M.B. and S.Gandhi acknowledge support from the STFC research grant ST/S000631/1. G.M.K. is supported by the Royal Society as a Royal Society University Research Fellow. F.M. acknowledges support from a Royal Society Dorothy Hodgkin Fellowship. K.G.S. acknowledges partial support from NASA grant 17-XRP17 2-0024. C.Z. is supported by a Dunlap Fellowship at the Dunlap Institute for Astronomy and Astrophysics, funded through an endowment established by the Dunlap family and the University of Toronto. A.W.M. was supported by NASA grant 80NSSC19K0097 to the University of North Carolina at Chapel Hill. D.J.A.B. acknowledges support from the UK Space Agency. C.X.H. and M.N.G. acknowledge support from the Juan Carlos Torres Fellowship. This work was financed by FEDER (Fundo Europeu de Desenvolvimento Regional) funds through the COMPETE 2020 Operational Programme for Competitiveness and Internationalisation (POCI) and by Portuguese funds through FCT (Fundação para a Ciência e a Tecnologia) in the framework of projects UID/FIS/04434/2019; PTDC/FIS-AST/32113/2017 and POCI-01-0145-FEDER-032113; PTDC/FIS-AST/28953/2017 and POCI-01-0145-FEDER-028953. S.G.S., V.A., S.C.C.B. and O.D.S.D. acknowledge support from FCT through Investigador FCT contracts IF/00028/2014/CP1215/CT0002, IF/00650/2015/CP1273/CT0001, IF/01312/2014/CP1215/CT0004 and DL 57/2016/CP1364/CT0004. S.H. acknowledges support from fellowships PD/BD/128119/2016 funded by FCT (Portugal). Work by J.N.W. was partly funded by the Heising-Simons Foundation. C.A.W. acknowledges support from UK Science Technology and Facility Council grant ST/P000312/1. J.L.-B. and D. Barrado are funded by the Spanish State Research Agency (AEI) Projects ESP2017-87676-C5-1-R and MDM-2017-0737 Unidad de Excelencia María de Maeztu – Centro de Astrobiología (INTA-CSIC). J.S.J. acknowledges funding by Fondecyt through grant 1161218 and partial support from CATA-Basal (PB06, Conicyt). J.I.V. acknowledges support from CONICYT-PFCHA/Doctorado Nacional-21191829, Chile. The French group acknowledges financial support from the French Programme National de Planétologie (PNP, INSU). F.M. acknowledges support from the Royal Society Dorothy Hodgkin Fellowship. C.M. and A.E. acknowledge support from the Swiss National Science Foundation under grant BSSGI0_155816 “PlanetsInTime”. Parts of this work have been carried out within the framework of the NCCR PlanetS supported by the Swiss National Science Foundation.
URI: http://hdl.handle.net/20.500.12666/159
E-ISSN: 1476-4687
Appears in Collections:(CAB) Artículos

Files in This Item:
File Description SizeFormat 
acceso-restringido.pdf221,73 kBAdobe PDFThumbnail
View/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.