KOI-126: A Triply Eclipsing Hierarchical Triple with Two Low-Mass Stars

• Published in: Science (American Association for the Advancement of Science) 2011-02, Vol.331 (6017), p.562-565
• Main Authors: Carter, Joshua A, Fabrycky, Daniel C, Ragozzine, Darin, Holman, Matthew J, Quinn, Samuel N, Latham, David W, Buchhave, Lars A, Van Cleve, Jeffrey, Cochran, William D, Cote, Miles T, Endl, Michael, Ford, Eric B, Haas, Michael R, Jenkins, Jon M, Koch, David G, Li, Jie, Lissauer, Jack J, MacQueen, Phillip J, Middour, Christopher K, Orosz, Jerome A, Rowe, Jason F, Steffen, Jason H, Welsh, William F
• Format: Article
• Language: English
• Subjects: Astronomical photometry; Astronomy; Average linear density; Benchmarking; Binary and multiple stars; Cadences; Earth, ocean, space; Eccentricity; Eclipses; Exact sciences and technology; Extrasolar planets; Kepler Objects of Interest; Keplerian orbits; Low mass stars; Monitoring; Multiple stars; Orbits; Photometry; Spacecraft; Stars; Stellar masses; Stellar radii
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1201274

The Kepler spacecraft has been monitoring the light from 150,000 stars in its primary quest to detect transiting exoplanets. Here, we report on the detection of an eclipsing stellar hierarchical triple, identified in the Kepler photometry. KOI-126 [A, (B, C)], is composed of a low-mass binary [masses MB = 0.2413 ± 0.0030 solar mass (M[middle dot in circle]), MC = 0.2127 ± 0.0026 M[middle dot in circle]; radii RB = 0.2543 ± 0.0014 solar radius (R[middle dot in circle]), RC = 0.2318 ± 0.0013 R[middle dot in circle]; orbital period P₁ = 1.76713 ± 0.00019 days] on an eccentric orbit about a third star (mass MA = 1.347 ± 0.032 M[middle dot in circle]; radius RA = 2.0254 ± 0.0098 R[middle dot in circle]; period of orbit around the low-mass binary P₂ = 33.9214 ± 0.0013 days; eccentricity of that orbit e₂ = 0.3043 ± 0.0024). The low-mass pair probe the poorly sampled fully convective stellar domain offering a crucial benchmark for theoretical stellar models.