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Updated: May 22, 2026

Surface Mapping of Earth-like Exoplanets using Single Point Light Curves
Published on: May 10, 2020
The detection and characterization of a nontransiting planet by transit timing variations
David Nesvorný1, David M Kipping, Lars A Buchhave
1Department of Space Studies, Southwest Research Institute, Boulder, CO 80302, USA. davidn@boulder.swri.edu
Abstract:
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 with the publicly available data for KOI-872. Planet b transits the host star with a period P(b) = 33.6 days 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) = 57.0 days) with a 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 6.8-day 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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