CaltechAUTHORS
Published November 2023 | Version Published
Journal Article Open

TOI-858 B b: A hot Jupiter on a polar orbit in a loose binary

Creators

  • 1. ROR icon University of Geneva
  • 2. ROR icon European Southern Observatory
  • 3. ROR icon University of Arizona
  • 4. ROR icon Princeton University
  • 5. ROR icon California Institute of Technology
  • 6. ROR icon Cerro Tololo Inter-American Observatory
  • 7. ROR icon Harvard-Smithsonian Center for Astrophysics
  • 8. ROR icon Yale University
  • 9. El Sauce Observatory, Río Hurtado, Coquimbo Province, Chile
  • 10. ROR icon Space Telescope Science Institute
  • 11. ROR icon University of Florida
  • 12. ROR icon Keele University
  • 13. ROR icon University of North Carolina at Chapel Hill
  • 14. Brierfield Observatory, Bowral NSW, 2576, Australia
  • 15. ROR icon Massachusetts Institute of Technology
  • 16. ROR icon Vanderbilt University
  • 17. Hazelwood Observatory, Victoria, Australia
  • 18. ROR icon Indiana University Bloomington
  • 19. ROR icon University of Toronto

Abstract

We report the discovery of a hot Jupiter on a 3.28-day orbit around a 1.08 M⊙ G0 star that is the secondary component in a loose binary system. Based on follow-up radial velocity observations of TOI-858 B with CORALIE on the Swiss 1.2 m telescope and CHIRON on the 1.5 m telescope at the Cerro Tololo Inter-American Observatory (CTIO), we measured the planet mass to be 1.10−0.07+0.08 MJ. Two transits were further observed with CORALIE to determine the alignment of TOI-858 B b with respect to its host star. Analysis of the Rossiter-McLaughlin signal from the planet shows that the sky-projected obliquity is λ = 99.3−3.7+3.8°. Numerical simulations show that the neighbour star TOI-858 A is too distant to have trapped the planet in a Kozai–Lidov resonance, suggesting a different dynamical evolution or a primordial origin to explain this misalignment. The 1.15 M⊙ primary F9 star of the system (TYC 8501-01597-1, at ρ ~11″) was also observed with CORALIE in order to provide upper limits for the presence of a planetary companion orbiting that star.

Copyright and License

© The Authors 2023. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Acknowledgement

We would like to thank the anonymous referee for the very constructive comments which significantly improved the scientific quality of the article. J.H. is supported by the Swiss National Science Foundation (SNSF) through the Ambizione grant #PZ00P2_180098. L.D.N. thanks the SNSF for support under Early Postdoc.Mobility grant #P2GEP2_200044. V.B. is supported by the National Centre for Competence in Research “PlanetS” from the SNSF. V.B. and M.A. are funded by the ERC under the European Union’s Horizon 2020 research and innovation programme (project SPICE DUNE, grant agreement no. 947634). A.B.D. was supported by the National Science Foundation Graduate Research Fellowship Program under Grant Number DGE-1122492. J.V. acknowledges support from the Swiss National Science Foundation (SNSF) under the Ambizione grant #PZ00P2_208945. Funding for the TESS mission is provided by NASA’s Science Mission Directorate. We acknowledge the use of public TESS data from pipelines at the TESS Science Office and at the TESS Science Processing Operations Center. This research has made use of the Exoplanet Follow-up Observation Program website, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. This research has made use of the Washington Double Star Catalog maintained at the US Naval Observatory, of the SIMBAD database, operated at CDS, Strasbourg, France, and of NASA’s Astrophysics Data System Bibliographic Services. This work made use of Astropy a community-developed core Python package and an ecosystem of tools and resources for astronomy (Astropy Collaboration 2013, 2018, 2022). It also made us of the python packages pandas (pandas development team 2020; McKinney 2010), scipy (Virtanen et al. 2020), matplotlib (Hunter 2007), and numpy (Harris et al. 2020).

Additional Information

Based on observations collected at the European Southern Observatory, Chile with the CORALIE echelle spectrograph mounted on the 1.2 m Swiss telescope at La Silla Observatory and with ESO HARPS Open Time (123.C-0123, 123.C-0123).

Files

aa44940-22.pdf

Files (2.5 MB)

Name Size Download all
md5:097e3e5d0d4b5bb901e075b4a05c28d3
2.5 MB Preview Download

Additional details

Related works

Is new version of
Discussion Paper: arXiv:2309.11390 (arXiv)
Is supplemented by
Dataset: https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/679/A70 (URL)

Funding

Swiss National Science Foundation
PZ00P2_180098
Swiss National Science Foundation
P2GEP2_200044
European Research Council
947634
National Science Foundation
DGE-1122492
Swiss National Science Foundation
PZ00P2_208945

Dates

Accepted
2023-08-17
Available
2023-11-08
Published online

Caltech Custom Metadata

Caltech groups
Division of Physics, Mathematics and Astronomy (PMA)
Publication Status
Published