NGTS-31b and NGTS-32b: two inflated hot Jupiters orbiting subgiant stars
ABSTRACT We present the discoveries of NGTS-31b(= TOI-2721), and NGTS-32b, two hot Jupiters from the Next Generation Transit Survey (NGTS) transiting slightly evolved stars. The orbital periods, radii, and masses are 4.16 and 3.31 d, 1.61 and 1.42 $R_{J}$, and 1.12 and 0.57 $M_{J}$, respectively. Both planets have an incident stellar flux significantly above the threshold where inflation occurs, with both planets showing signs of inflation. These planets have widely different equilibrium temperatures than other hot Jupiters of similar mass and radius, with NGTS-31b having a significantly lower temperature, and NGTS-32b being hotter. This dichotomy raises the question of how prevalent the roles of other inflation mechanisms are in the radius anomaly phenomena and will help further constrain different inflationary models.
Authors
- Thiam-Guan Tan (ORCID: https://orcid.org/0000-0001-5603-6895)
- Maximiliano Moyano (ORCID: https://orcid.org/0000-0002-7927-9555)
- F. Bouchy (ORCID: https://orcid.org/0000-0002-7613-393X)
- A. M. S. Smith (ORCID: https://orcid.org/0000-0002-2386-4341)
- J. McCormac (ORCID: https://orcid.org/0000-0003-1631-4170)
- M. R. Burleigh (ORCID: https://orcid.org/0000-0003-0684-7803)
- Maximilian N. Günther (ORCID: https://orcid.org/0000-0002-3164-9086)
- Philipp Eigmüller (ORCID: https://orcid.org/0000-0003-4096-0594)
- R. G. West (ORCID: https://orcid.org/0000-0001-6604-5533)
- M. Lendl (ORCID: https://orcid.org/0000-0001-9699-1459)
- Edward Gillen (ORCID: https://orcid.org/0000-0003-2851-3070)
- Daniel Bayliss (ORCID: https://orcid.org/0000-0001-6023-1335)
- M. R. Goad (ORCID: https://orcid.org/0000-0002-2908-7360)
- Karen A. Collins (ORCID: https://orcid.org/0000-0001-6588-9574)
- Alicia Kendall (ORCID: https://orcid.org/0009-0006-0719-9229)
- S. L. Casewell (ORCID: https://orcid.org/0000-0003-2478-0120)
- Samuel Gill (ORCID: https://orcid.org/0000-0002-4259-0155)
- J. S. Jenkins (ORCID: https://orcid.org/0000-0003-2733-8725)
- Sara Seager (ORCID: https://orcid.org/0000-0002-6892-6948)
- Pamela Rowden (ORCID: https://orcid.org/0000-0002-4829-7101)
- Gavin Ramsay (ORCID: https://orcid.org/0000-0001-8722-9710)
- Ben Falk
- Khalid Barkaoui (ORCID: https://orcid.org/0000-0003-1464-9276)
- G. Ricker (ORCID: https://orcid.org/0000-0003-2058-6662)
- Rosanna H Tilbrook (ORCID: https://orcid.org/0000-0002-2023-4029)
- P. J. Wheatley (ORCID: https://orcid.org/0000-0003-1452-2240)
- Ares Osborn (ORCID: https://orcid.org/0000-0002-5899-7750)
- Jack S Acton (ORCID: https://orcid.org/0000-0002-1860-7842)
- Edward M. Bryant (ORCID: https://orcid.org/0000-0001-7904-4441)
- Louise D. Nielsen (ORCID: https://orcid.org/0000-0002-5254-2499)
- Beth A Henderson (ORCID: https://orcid.org/0000-0002-2813-3994)
- José I Vines (ORCID: https://orcid.org/0000-0002-1896-2377)
- D. R. Anderson (ORCID: https://orcid.org/0000-0001-7416-7522)
- Jessie L. Christiansen (ORCID: https://orcid.org/0000-0002-8035-4778)
- Suman Saha (ORCID: https://orcid.org/0000-0001-8018-0264)
- S. Udry (ORCID: https://orcid.org/0000-0001-7576-6236)
- Ioannis Apergis (ORCID: https://orcid.org/0009-0004-7473-4573)
- Tafadzwa Zivave (ORCID: https://orcid.org/0009-0001-8055-995X)
- D. R. Alves (ORCID: https://orcid.org/0000-0002-5619-2502)
- Alexander Rudat
- Joshua N. Winn
Institutions
- University of Geneva (CH)
- California Institute of Technology (US)
- Royal Astronomical Society (GB)
- Space Telescope Science Institute (US)
- European Southern Observatory (DE)
- University of Leicester (GB)
- Queen Mary University of London (GB)
- Princeton University (US)
- Armagh Observatory & Planetarium (GB)
- NASA Exoplanet Science Institute (US)
- Universidad Católica del Norte (CL)
- Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR) (DE)
- Department of Space (IN)
- University of Warwick (GB)
- Chinese Academy of Science South America Center for Astronomy (CL)
- Millennium Institute of Astrophysics (CL)
- Perth Exoplanet Survey Telescope Observatory (AU)
- Université Bourgogne Franche-Comté (FR)
- Center for Astrophysics Harvard & Smithsonian (US)
- Centro de Astrofísica y Tecnologías Afines (CL)
- European Space Research and Technology Centre (NL)
- University College London (GB)
- American Institute of Aeronautics and Astronautics (US)
- Massachusetts Institute of Technology (US)
- University of Chile (CL)
- Universidad Diego Portales (CL)
Publication Details
- Journal
- Monthly Notices of the Royal Astronomical Society
- Published
- 2024-11-27
- DOI
- https://doi.org/10.1093/mnras/stae2616
- Primary Topic
- Astro and Planetary Science
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Science Foundation
- National Aeronautics and Space Administration
- California Institute of Technology
- European Commission
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Agencia Nacional de Investigación y Desarrollo
- Science Mission Directorate
- Science and Technology Facilities Council
- Comisión Nacional de Investigación Científica y Tecnológica