An ultrahot gas-giant exoplanet with a stratosphere

Thomas M Evans¹, David K Sing¹, Tiffany Kataria², Jayesh Goyal¹, Nikolay Nikolov¹, Hannah R Wakeford³, Drake Deming⁴, Mark S Marley⁵, David S Amundsen^{6

7}, Gilda E Ballester⁸, Joanna K Barstow⁹, Lotfi Ben-Jaffel¹⁰, Vincent Bourrier¹¹, Lars A Buchhave¹², Ofer Cohen¹³, David Ehrenreich¹¹, Antonio García Muñoz¹⁴, Gregory W Henry¹⁵, Heather Knutson¹⁶, Panayotis Lavvas¹⁷, Alain Lecavelier des Etangs¹⁰, Nikole K Lewis¹⁸, Mercedes López-Morales¹⁹, Avi M Mandell³, Jorge Sanz-Forcada²⁰, Pascal Tremblin²¹, Roxana Lupu²²

Affiliations

¹ Astrophysics Group, School of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL, UK.
² NASA Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, California 91109, USA.
³ NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA.
⁴ Department of Astronomy, University of Maryland, College Park, Maryland 20742, USA.
⁵ NASA Ames Research Center, MS 245-5, Moffett Field, California 94035, USA.
⁶ Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10025, USA.
⁷ NASA Goddard Institute for Space Studies, New York, New York 10025, USA.
⁸ Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona 85721, USA.
⁹ Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK.
¹⁰ Sorbonne Universités, UPMC Université Paris 6 and CNRS, UMR 7095, Institut d'Astrophysique de Paris, 98 bis boulevard Arago, F-75014 Paris, France.
¹¹ Observatoire de l'Université de Genève, 51 chemin des Maillettes, 1290 Sauverny, Switzerland.
¹² Centre for Star and Planet Formation, Niels Bohr Institute and Natural History Museum, University of Copenhagen, DK-1350 Copenhagen, Denmark.
¹³ Lowell Center for Space Science and Technology, University of Massachusetts, Lowell, Massachusetts 01854, USA.
¹⁴ Zentrum für Astronomie und Astrophysik, Technische Universität Berlin, D-10623 Berlin, Germany.
¹⁵ Center of Excellence in Information Systems, Tennessee State University, Nashville, Tennessee 37209, USA.
¹⁶ Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, USA.
¹⁷ Groupe de Spectrométrie Moléculaire et Atmosphérique, UMR 7331, CNRS, Université de Reims Champagne-Ardenne, Reims 51687, France.
¹⁸ Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, Maryland 21218, USA.
¹⁹ Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA.
²⁰ Centro de Astrobiología (CSIC-INTA), ESAC Campus, Camino bajo del Castillo, E-28692 Villanueva de la Cañada, Madrid, Spain.
²¹ Maison de la Simulation, CEA, CNRS, Université Paris-Sud, UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France.
²² Bay Area Environmental Research Institute, Moffett Field, California 94035, USA.

PMID: 28770846
DOI: 10.1038/nature23266

Free article

An ultrahot gas-giant exoplanet with a stratosphere

Thomas M Evans et al. Nature. 2017.

Free article

. 2017 Aug 2;548(7665):58-61.

doi: 10.1038/nature23266.

Authors

Affiliations

¹ Astrophysics Group, School of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL, UK.
² NASA Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, California 91109, USA.
³ NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA.
⁴ Department of Astronomy, University of Maryland, College Park, Maryland 20742, USA.
⁵ NASA Ames Research Center, MS 245-5, Moffett Field, California 94035, USA.
⁶ Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10025, USA.
⁷ NASA Goddard Institute for Space Studies, New York, New York 10025, USA.
⁸ Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona 85721, USA.
⁹ Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK.
¹⁰ Sorbonne Universités, UPMC Université Paris 6 and CNRS, UMR 7095, Institut d'Astrophysique de Paris, 98 bis boulevard Arago, F-75014 Paris, France.
¹¹ Observatoire de l'Université de Genève, 51 chemin des Maillettes, 1290 Sauverny, Switzerland.
¹² Centre for Star and Planet Formation, Niels Bohr Institute and Natural History Museum, University of Copenhagen, DK-1350 Copenhagen, Denmark.
¹³ Lowell Center for Space Science and Technology, University of Massachusetts, Lowell, Massachusetts 01854, USA.
¹⁴ Zentrum für Astronomie und Astrophysik, Technische Universität Berlin, D-10623 Berlin, Germany.
¹⁵ Center of Excellence in Information Systems, Tennessee State University, Nashville, Tennessee 37209, USA.
¹⁶ Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, USA.
¹⁷ Groupe de Spectrométrie Moléculaire et Atmosphérique, UMR 7331, CNRS, Université de Reims Champagne-Ardenne, Reims 51687, France.
¹⁸ Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, Maryland 21218, USA.
¹⁹ Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA.
²⁰ Centro de Astrobiología (CSIC-INTA), ESAC Campus, Camino bajo del Castillo, E-28692 Villanueva de la Cañada, Madrid, Spain.
²¹ Maison de la Simulation, CEA, CNRS, Université Paris-Sud, UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France.
²² Bay Area Environmental Research Institute, Moffett Field, California 94035, USA.

PMID: 28770846
DOI: 10.1038/nature23266

Abstract

Infrared radiation emitted from a planet contains information about the chemical composition and vertical temperature profile of its atmosphere. If upper layers are cooler than lower layers, molecular gases will produce absorption features in the planetary thermal spectrum. Conversely, if there is a stratosphere-where temperature increases with altitude-these molecular features will be observed in emission. It has been suggested that stratospheres could form in highly irradiated exoplanets, but the extent to which this occurs is unresolved both theoretically and observationally. A previous claim for the presence of a stratosphere remains open to question, owing to the challenges posed by the highly variable host star and the low spectral resolution of the measurements. Here we report a near-infrared thermal spectrum for the ultrahot gas giant WASP-121b, which has an equilibrium temperature of approximately 2,500 kelvin. Water is resolved in emission, providing a detection of an exoplanet stratosphere at 5σ confidence. These observations imply that a substantial fraction of incident stellar radiation is retained at high altitudes in the atmosphere, possibly by absorbing chemical species such as gaseous vanadium oxide and titanium oxide.

PubMed Disclaimer

References

1. Icarus. 1999 Apr;138(2):268-86 - PubMed
1. Science. 2014 Nov 14;346(6211):838-41 - PubMed
1. Nature. 2016 Jan 7;529(7584):59-62 - PubMed
1. Science. 2017 May 12;356(6338):628-631 - PubMed

Publication types

Actions
Actions

LinkOut - more resources

Full Text Sources
Other Literature Sources
- scite Smart Citations

Save citation to file

Email citation

Add to Collections

Add to My Bibliography

Your saved search

Create a file for external citation management software

Your RSS Feed

An ultrahot gas-giant exoplanet with a stratosphere

Affiliations

An ultrahot gas-giant exoplanet with a stratosphere

Authors

Affiliations

Abstract

References

Publication types

LinkOut - more resources

Full Text Sources

Other Literature Sources