2003/01/01 by Laura Kreidberg, Daniel D. B. Koll, Caroline Morley +17
Medicine · Physics and Astronomy · #Allele #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Atmosphere (unit) #Biology #Brightness #Cystic Fibrosis Research Advances #Cystic fibrosis #Cystic fibrosis transmembrane conductance regulator #Exon #Exoplanet #Gene #Genetics #Genotype #Longitude #Medicine #Molecular biology #Mutation #Neonatal Respiratory Health Research #Planet #Population #Single-nucleotide polymorphism #Single-strand conformation polymorphism #Stars #Stellar, planetary, and galactic studies #Terrestrial planet #Tidal heating #Tidal locking #astro-ph.EP #ΔF508
paper · pdf · doi:10.1038/s41586-019-1497-4
Published in Nature on Aug 19, 2019. Co-authors Koll, Morley and Hu contributed equally to this manuscript
openalex publication_date 2003/01/01 · arxiv created 2019/08/19 · arxiv updated 2019/08/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/04
Most known terrestrial planets orbit small stars with radii less than 60 per cent of that of the Sun<sup>1,2</sup>. Theoretical models predict that these planets are more vulnerable to atmospheric loss than their counterparts orbiting Sun-like stars<sup>3-6</sup>. To determine whether a thick atmosphere has survived on a small planet, one approach is to search for signatures of atmospheric heat redistribution in its thermal phase curve<sup>7-10</sup>. Previous phase curve observations of the super-Earth 55 Cancri e (1.9 Earth radii) showed that its peak brightness is offset from the substellar point (latitude and longitude of 0 degrees)-possibly indicative of atmospheric circulation<sup>11</sup>. Here we report a phase curve measurement for the smaller, cooler exoplanet LHS 3844b, a 1.3-Earth-radii world in an 11-hour orbit around the small nearby star LHS 3844. The observed phase variation is symmetric and has a large amplitude, implying a dayside brightness temperature of 1,040 ± 40 kelvin and a nightside temperature consistent with zero kelvin (at one standard deviation). Thick atmospheres with surface pressures above 10 bar are ruled out by the data (at three standard deviations), and less-massive atmospheres are susceptible to erosion by stellar wind. The data are well fitted by a bare-rock model with a low Bond albedo (lower than 0.2 at two standard deviations). These results support theoretical predictions that hot terrestrial planets orbiting small stars may not retain substantial atmospheres.