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The Detection and Characterization of a Nontransiting Planet by Transit Timing Variations

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 نشر من قبل David Kipping
 تاريخ النشر 2012
  مجال البحث فيزياء
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The Kepler Mission is monitoring the brightness of ~150,000 stars searching for evidence of planetary transits. As part of the Hunt for Exomoons with Kepler (HEK) project, we report a planetary system with two confirmed planets and one candidate planet discovered using the publicly available data for KOI-872. Planet b transits the host star with a period P_b=33.6d and exhibits large transit timing variations indicative of a perturber. Dynamical modeling uniquely detects an outer nontransiting planet c near the 5:3 resonance (P_c=57.0d) of mass 0.37 times that of Jupiter. Transits of a third planetary candidate are also found: a 1.7-Earth radius super-Earth with a 6.8d period. Our analysis indicates a system with nearly coplanar and circular orbits, reminiscent of the orderly arrangement within the solar system.



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