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arXiv · 1304.4283

KOI-142, the King of Transit Variations, is a Pair of Planets near the 2:1 Resonance

David Nesvorny·David Kipping·Dirk Terrell·Joel Hartman·Gaspar A. Bakos·Lars A. Buchhave
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Abstract

The Transit Timing Variations (TTVs) can be used as a diagnostic of gravitational interactions between planets in a multi-planet system. Many Kepler Objects of Interest (KOIs) exhibit significant TTVs, but KOI-142.01 stands out among them with an unrivaled, 12-hour TTV amplitude. Here we report a thorough analysis of KOI-142.01's transits. We discover periodic Transit Duration Variations (TDVs) of KOI-142.01 that are nearly in phase with the observed TTVs. We show that KOI-142.01's TTVs and TDVs uniquely detect a non-transiting companion with a mass 0.7 that of Jupiter (KOI-142c). KOI-142.01's mass inferred from the transit variations is consistent with the measured transit depth, suggesting a Neptune class planet (KOI-142b). The orbital period ratio P_c/P_b=2.03 indicates that the two planets are just wide of the 2:1 resonance. The present dynamics of this system, characterized here in detail, can be used to test various formation theories that have been proposed to explain the near-resonant pairs of exoplanets.

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David Nesvorny, David Kipping, Dirk Terrell, Joel Hartman, Gaspar A. Bakos, Lars A. Buchhave. 2013-04-15. KOI-142, the King of Transit Variations, is a Pair of Planets near the 2:1 Resonance. https://doi.org/10.1088/0004-637x%2F777%2F1%2F3

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