Europlanet Science Congress 2021
Virtual meeting
13 – 24 September 2021
Europlanet Science Congress 2021
Virtual meeting
13 September – 24 September 2021
EPSC Abstracts
Vol. 15, EPSC2021-571, 2021
European Planetary Science Congress 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

A Systematic Characterization of the HR8799 System with GRAVITY

Evert Nasedkin1, Paul Molliere1, and the ExoGRAVITY*
Evert Nasedkin and Paul Molliere and the ExoGRAVITY
  • 1Max Planck Institute for Astronomy, APEx, Germany (
  • *A full list of authors appears at the end of the abstract

The four planets of the HR8799 system provide a benchmark for directly imaged exoplanets. As these planets share a formation history, variations between the planet’s atmospheric properties - likely tracing their individual formation pathways - could provide insight into the details of the process of planet formation. In order explore these atmospheres and their evolution, we use new data obtained with the GRAVITY instrument at the VLTI as part of the ExoGRAVITY campaign, combined with data from SPHERE, GPI, CHARIS, ALES and OSIRIS in order to provide the best picture of the planetary atmospheres across a broad wavelength range. Using petitRADTRANS in a Bayesian retrieval framework, we compare a suite of state-of-the-art models applied to each of the targets in order to measure atmospheric properties such as metallicity, molecular abundances, and the C/O ratio, which is a well known tracer of the formation history. In this talk I will describe the data processing and modelling efforts which allow us to peer into the atmospheres of the HR8799 planets, and will outline the steps needed to tie the newly retrieved planetary properties to the formation history of the system.


S. Lacour, J. J. Wang, M. Nowak, L. Pueyo, F. Eisenhauer, A.-M. Lagrange, R. Abuter, A. Amorim, R. Asensio-Torres, M. Bauböck, M. Benisty, J.P. Berger, H. Beust, B. Biller, S. Blunt, A. Boccaletti, A. Bohn, M. Bonnefoy, H. Bonnet, W. Brandner, F. Cantalloube, P. Caselli, B. Charnay, G. Chauvin, E. Choquet, V. Christiaens, Y. Clénet, A. Cridland, P.T. de Zeeuw, R. Dembet, J. Dexter, D. Doelman, A. Drescher, G. Duvert, F. Gao, P. Garcia, R. Garcia Lopez, T. Gardner, E. Gendron, R. Genzel, S. Gillessen, J. H. Girard, A. Greenbaum, X. Haubois, G. Heissel, T. Henning, S. Hinkley, S. Hippler, M. Horrobin, M. Houllé, Z. Hubert, A. Jiménez-Rosales, L. Jocou, J. Kammerer, M. Keppler, P. Kervella, L. Kreidberg, V. Lapeyrère, J.-B. Le Bouquin, P. Léna, D. Lutz, A.-L. Maire, A. Mérand, J.D. Monnier, D. Mouillet, A. Muller, T. Ott, G. P. P. L. Otten, C. Paladini, T. Paumard, K. Perraut, G. Perrin, O. Pfuhl, J. Rameau, L. Rodet, G. Rodriguez-Coira, G. Rousset, J. Shangguan, D. Sing, T. Shimizu, J. Stadler, O. Straub, C. Straubmeier, E. Sturm, T. Stolker, E.F. van Dishoeck, A. Vigan, F. Vincent, S.D. von Fellenberg, K. Ward-Duong, F. Widmann, E. Wieprecht, E. Wiezorrek, J. Woillez, A. Zurlo

How to cite: Nasedkin, E. and Molliere, P. and the ExoGRAVITY: A Systematic Characterization of the HR8799 System with GRAVITY, European Planetary Science Congress 2021, online, 13–24 Sep 2021, EPSC2021-571,, 2021.

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