We report the detection of Kepler-47, a system consisting of two planets orbiting around an eclipsing pair of stars. The inner and outer planets have radii 3.0 and 4.6 times that of the Earth, respectively. The binary star consists of a Sun-like star and a companion roughly one-third its size, orbiting each other every 7.45 days. With an orbital period of 49.5 days, eighteen transits of the inner planet have been observed, allowing a detailed characterization of its orbit and those of the stars. The outer planet's orbital period is 303.2 days, and although the planet is not Earth-like, it resides within the classical "habitable zone", where liquid water could exist on an Earth-like planet. With its two known planets, Kepler-47 establishes that close binary stars can host complete planetary systems.
@article{arxiv.1208.5489,
title = {Kepler-47: A Transiting Circumbinary Multi-Planet System},
author = {Jerome A. Orosz and William F. Welsh and Joshua A. Carter and Daniel C. Fabrycky and William D. Cochran and Michael Endl and Eric B. Ford and Nader Haghighipour and Phillip J. MacQueen and Tsevi Mazeh and Roberto Sanchis-Ojeda and Donald R. Short and Guillermo Torres and Eric Agol and Lars A. Buchhave and Laurance R. Doyle and Howard Isaacson and Jack J. Lissauer and Geoffrey W. Marcy and Avi Shporer and Gur Windmiller and Thomas Barclay and Alan P. Boss and Bruce D. Clarke and Jonathan Fortney and John C. Geary and Matthew J. Holman and Daniel Huber and Jon M. Jenkins and Karen Kinemuchi and Ethan Kruse and Darin Ragozzine and Dimitar Sasselov and Martin Still and Peter Tenenbaum and Kamal Uddin and Joshua N. Winn and David G. Koch and William J. Borucki},
journal= {arXiv preprint arXiv:1208.5489},
year = {2015}
}
Comments
To appear on Science Express August 28, 11 pages, 3 figures, one table (main text), 56 pages, 28 figures, 10 tables