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Kepler-9: A System of Multiple Planets Transiting a Sun-Like Star, Confirmed by Timing Variations

Holman, Matthew J. and Ciardi, David R. and Johnson, John A. (2010) Kepler-9: A System of Multiple Planets Transiting a Sun-Like Star, Confirmed by Timing Variations. Science, 330 (6000). pp. 51-54. ISSN 0036-8075.

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The Kepler spacecraft is monitoring more than 150,000 stars for evidence of planets transiting those stars. We report the detection of two Saturn-size planets that transit the same Sun-like star, based on 7 months of Kepler observations. Their 19.2- and 38.9-day periods are presently increasing and decreasing at respective average rates of 4 and 39 minutes per orbit; in addition, the transit times of the inner body display an alternating variation of smaller amplitude. These signatures are characteristic of gravitational interaction of two planets near a 2:1 orbital resonance. Six radial-velocity observations show that these two planets are the most massive objects orbiting close to the star and substantially improve the estimates of their masses. After removing the signal of the two confirmed giant planets, we identified an additional transiting super-Earth–size planet candidate with a period of 1.6 days.

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Ciardi, David R.0000-0002-5741-3047
Additional Information:© 2010 American Association for the Advancement of Science. Received 28 July 2010; accepted 19 August 2010. Published online 26 August 2010. Funding for this Discovery mission is provided by NASA’s Science Mission Directorate. We acknowledge NASA Cooperative Agreement NCC2-1390. D.C.F. acknowledges support from the Michelson Fellowship, supported by NASA and administered by the NASA Exoplanet Science Institute. This material is based on work supported by the NSF under grant no. 0707203. This work is based, in part, on observations obtained at the W. M. Keck Observatory, which is operated by the Univ. of California and the California Institute of Technology. Some of the observations in this paper were obtained at Kitt Peak National Observatory, National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy under cooperative agreement with the NSF. J.F.R. is a NASA postdoctoral program fellow. We are grateful to N. Haghighipour for many helpful comments and suggestions.
Group:Infrared Processing and Analysis Center (IPAC)
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NASA Michelson FellowshipUNSPECIFIED
Record Number:CaltechAUTHORS:20101022-141052585
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:20487
Deposited By: Tony Diaz
Deposited On:30 Nov 2010 20:27
Last Modified:28 Mar 2017 22:12

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