Planet Hunters TESS V: a planetary system around a binary star, including a mini-Neptune in the habitable zone
Abstract
We report on the discovery and validation of a transiting long-period mini-Neptune orbiting a bright (V = 9.0 mag) G dwarf (TOI 4633; R = 1.05 RSun, M = 1.10 MSun). The planet was identified in data from the Transiting Exoplanet Survey Satellite by citizen scientists taking part in the Planet Hunters TESS project. Modeling of the transit events yields an orbital period of 271.9445 +/- 0.0040 days and radius of 3.2 +/- 0.20 REarth. The Earth-like orbital period and an incident flux of 1.56 +/- 0.2 places it in the optimistic habitable zone around the star. Doppler spectroscopy of the system allowed us to place an upper mass limit on the transiting planet and revealed a non-transiting planet candidate in the system with a period of 34.15 +/- 0.15 days. Furthermore, the combination of archival data dating back to 1905 with new high angular resolution imaging revealed a stellar companion orbiting the primary star with an orbital period of around 230 years and an eccentricity of about 0.9. The long period of the transiting planet, combined with the high eccentricity and close approach of the companion star makes this a valuable system for testing the formation and stability of planets in binary systems.
Cite
@article{arxiv.2404.18997,
title = {Planet Hunters TESS V: a planetary system around a binary star, including a mini-Neptune in the habitable zone},
author = {Nora L. Eisner and Samuel K. Grunblatt and Oscar Barragán and Thea H. Faridani and Chris Lintott and Suzanne Aigrain and Cole Johnston and Ian R. Mason and Keivan G. Stassun and Megan Bedell and Andrew W. Boyle and David R. Ciardi and Catherine A. Clark and Guillaume Hebrard and David W. Hogg and Steve B. Howell and Baptiste Klein and Joe Llama and Joshua N. Winn and Lily L. Zhao and Joseph M. Akana Murphy and Corey Beard and Casey L. Brinkman and Ashley Chontos and Pia Cortes-Zuleta and Xavier Delfosse and Steven Giacalone and Emily A. Gilbert and Neda Heidari and Rae Holcomb and Jon M. Jenkins and Flavien Kiefer and Jack Lubin and Eder Martioli and Alex S. Polanski and Nicholas Saunders and Sara Seager and Avi Shporer and Dakotah Tyler and Judah Van Zandt and Safaa Alhassan and Daval J. Amratlal and Lais I. Antonel and Simon L. S. Bentzen and Milton K. D. Bosch and David Bundy and Itayi Chitsiga and Jérôme F. Delaunay and Xavier Doisy and Richard Ferstenou and Mark Fynø and James M. Geary and Gerry Haynaly and Pete Hermes and Marc Huten and Sam Lee and Paul Metcalfe and Garry J. Pennell and Joanna Puszkarska and Thomas Schäfer and Lisa Stiller and Christopher Tanner and Allan Tarr and Andrew Wilkinson},
journal= {arXiv preprint arXiv:2404.18997},
year = {2024}
}
Comments
24 pages, 16 figures, 4 tables