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Title: LHS 475 b: A Potential Venus Analog Orbiting a Nearby M Dwarf
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 ± 0.015M. 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 ± 0.058R. 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.

 
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NSF-PAR ID:
10499170
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astronomical Journal
Volume:
167
Issue:
5
ISSN:
0004-6256
Format(s):
Medium: X Size: Article No. 197
Size(s):
Article No. 197
Sponsoring Org:
National Science Foundation
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