We report the discovery and characterization of TOI-2005b, a warm Jupiter on an eccentric (e~0.59), 17.3-day orbit around a V_mag = 9.867 rapidly rotating F-star. The object was detected as a candidate by TESS and the planetary nature of TOI-2005b was then confirmed via a series of ground-based photometric, spectroscopic, and diffraction-limited imaging observations. The planet was found to reside in a low sky-projected stellar obliquity orbit (lambda = 4.8 degrees) via a transit spectroscopic observation using the Magellan MIKE spectrograph.TOI-2005b is one of a few planets known to have a low-obliquity, high-eccentricity orbit, which may be the result of high-eccentricity coplanar migration. The planet has a periastron equilibrium temperature of ~ 2100 K, similar to some highly irradiated hot Jupiters where atomic metal species have been detected in transmission spectroscopy, and varies by almost 1000 K during its orbit. Future observations of the atmosphere of TOI-2005b can inform us about its radiative timescales thanks to the rapid heating and cooling of the planet.
@article{arxiv.2503.20069,
title = {TOI-2005b: An Eccentric Warm Jupiter in Spin-Orbit Alignment},
author = {Allyson Bieryla and Jiayin Dong and George Zhou and Jason D. Eastman and L. C. Mayorga and David W. Latham and Brad Carter and Chelsea X. Huang and Samuel N. Quinn and Karen A. Collins and Lyu Abe and Yuri Beletsky and Rafael Brahm and Nicole D. Colón and Zahra Ensak and Tristan Guillot and Thomas Henning and Melissa J. Hobson and Keith Horne and Jon M. Jenkins and Matías I. Jones and Andrés Jordán and David Osip and George R. Ricker and Joseph E. Rodriguez and Jack Schulte and Richard P. Schwarz and Sara Seager and Avi Shporer and Olga Suarez and Thiam-Guan Tan and Eric B. Ting and Amaury Triaud and Andrew Vanderburg and Jesus Noel Villanseñor and Noah Vowell and Christilyn N. Watkins and Joshua N. Winn and Carl Ziegler},
journal= {arXiv preprint arXiv:2503.20069},
year = {2025}
}