Kepler-7b: A Transiting Planet with Unusually Low Density

David W. Latham; William J. Borucki; David G. Koch; Timothy M. Brown; Lars A. Buchhave; Gibor Basri; Natalie M. Batalha; Douglas A. Caldwell; William D. Cochran; Edward W. Dunham; Gabor Furesz; Thomas N. Gautier III; John C. Geary; Ronald L. Gilliland; Steve B. Howell; Jon M. Jenkins; Jack J. Lissauer; Geoffrey W. Marcy; David G. Monet; Jason F. Rowe; Dimitar D. Sasselov

doi:10.1088/2041-8205/713/2/l140

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arXiv · 1001.0190

Kepler-7b: A Transiting Planet with Unusually Low Density

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Abstract

We report the discovery and confirmation of Kepler-7b, a transiting planet with unusually low density. The mass is less than half that of Jupiter, Mp = 0.43 Mj, but the radius is fifty percent larger, Rp = 1.48 Rj. The resulting density, 0.17 g/cc, is the second lowest reported so far for an extrasolar planet. The orbital period is fairly long, P = 4.886 days, and the host star is not much hotter than the Sun, Teff = 6000 K. However, it is more massive and considerably larger than the sun, Mstar = 1.35 Msun and Rstar = 1.84 Rsun, and must be near the end of its life on the Main Sequence.

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David W. Latham, William J. Borucki, David G. Koch, Timothy M. Brown, Lars A. Buchhave, Gibor Basri, Natalie M. Batalha, Douglas A. Caldwell, William D. Cochran, Edward W. Dunham, Gabor Furesz, Thomas N. Gautier III, John C. Geary, Ronald L. Gilliland, Steve B. Howell, Jon M. Jenkins, Jack J. Lissauer, Geoffrey W. Marcy, David G. Monet, Jason F. Rowe, Dimitar D. Sasselov. 2009-12-31. Kepler-7b: A Transiting Planet with Unusually Low Density. https://doi.org/10.1088/2041-8205%2F713%2F2%2Fl140

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