LHS 475 b: A Potential Venus Analog Orbiting a Nearby M Dwarf

• Published in: The Astronomical journal Vol. 167; no. 5; pp. 197 - 207
• Main Authors: Ment, Kristo, Charbonneau, David, Irwin, Jonathan, Winters, Jennifer G., Pass, Emily, Shporer, Avi, Collins, Karen A., Collins, Kevin I., Jensen, Eric L. N., Schwarz, Richard P., Horne, Keith, Essack, Zahra, Kostov, Veselin B., Kunimoto, Michelle, Levine, Alan, Seager, Sara, Vanderspek, Roland, Winn, Joshua N.
• Format: Journal Article
• Language: English
• Published: Madison The American Astronomical Society 01-05-2024; IOP Publishing
• Subjects: Exoplanets; Extrasolar planets; Extrasolar rocky planets; Ground-based observation; Orbits; Photometric observations; Photometry; Planet formation; Radial velocity; Spectroscopy; Transit photometry; Velocity; Venus
• ISSN: 0004-6256; 1538-3881
• DOI: 10.3847/1538-3881/ad1b58

Abstract Based on photometric observations by TESS, we present the discovery of a potential Venus analog transiting LHS 475, an M3 dwarf located 12.5 pc from the Sun. The mass of the star is 0.274 ± 0.015 M ☉ . The planet, originally reported as TOI 910.01, has an orbital period of 2.0291010 ± 0.0000017 days and an estimated radius of 0.975 ± 0.058 R ⊕ . We confirm the validity and source of the transit signal with MEarth and Las Cumbres Observatory Global Telescope ground-based follow-up photometry. We present radial velocity data from CHIRON that rule out massive companions. In accordance with the observed mass–radius distribution of exoplanets as well as planet formation theory, we expect this planetary companion to be terrestrial, with an estimated radial velocity semiamplitude of 1.1 m s −1 . LHS 475 b is likely too hot to be habitable but is a suitable candidate for emission and transmission spectroscopy.