Daniel Johns, Kutztown University
Phillip A. Reed, Kutztown University
Joseph E. Rodriguez, Harvard-Smithsonian Center for Astrophysics
Joshua Pepper, Lehigh University
Keivan G. Stassun, Vanderbilt University
Kaloyan Penev, The University of Texas at Dallas
B. Scott Gaudi, The Ohio State University
Jonathan Labadie-Bartz, Universidade de São Paulo
Benjamin J. Fulton, California Institute of Technology
Samuel N. Quinn, Harvard-Smithsonian Center for Astrophysics
Jason D. Eastman, Harvard-Smithsonian Center for Astrophysics
David R. Ciardi, California Institute of Technology
Lea Hirsch, Kavli Institute for Particle Astrophysics and Cosmology
Daniel J. Stevens, Pennsylvania State University
Catherine P. Stevens, Westminster College, New Wilmington
Thomas E. Oberst, Westminster College, New Wilmington
David H. Cohen, Swarthmore College
Eric L.N. Jensen, Swarthmore College
Paul Benni, Acton Sky Portal (Private Observatory)
Steven Villanueva, The Ohio State University
Gabriel Murawski, Gabriel Murawski Private Observatory
Allyson Bieryla, Harvard-Smithsonian Center for Astrophysics
David W. Latham, Harvard-Smithsonian Center for Astrophysics
Siegfried Vanaverbeke, IRIS
Franky Dubois, IRIS
Steve Rau, IRIS
Ludwig Logie, IRIS
Ryan F. Rauenzahn, Kutztown University
Robert A. Wittenmyer, University of Southern Queensland
Roberto Zambelli, Societ Astronomica Lunae
Daniel Bayliss, Australian National University, Mount Stromlo Observatory
Thomas G. Beatty, Pennsylvania State University
Karen A. Collins, Harvard-Smithsonian Center for Astrophysics

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We announce the discovery of KELT-23Ab, a hot Jupiter transiting the relatively bright (V = 10.3) star BD+66 911 (TYC 4187-996-1), and characterize the system using follow-up photometry and spectroscopy. A global fit to the system yields host-star properties of K, , , , (cgs), and . KELT-23Ab is a hot Jupiter with a mass of , radius of , and density of g cm-3. Intense insolation flux from the star has likely caused KELT-23Ab to become inflated. The time of inferior conjunction is and the orbital period is days. There is strong evidence that KELT-23A is a member of a long-period binary star system with a less luminous companion, and due to tidal interactions, the planet is likely to spiral into its host within roughly a gigayear. This system has one of the highest positive ecliptic latitudes of all transiting planet hosts known to date, placing it near the Transiting Planet Survey Satellite and James Webb Space Telescope continuous viewing zones. Thus we expect it to be an excellent candidate for long-term monitoring and follow up with these facilities.

Publication Source (Journal or Book title)

Astronomical Journal