* Astronomy

Title: Transits and occultations of an Earth-sized planet in an 8.5-hour orbit
Authors: Roberto Sanchis-Ojeda, Saul Rappaport, Joshua N. Winn, Alan M. Levine, Michael C. Kotson, David W. Latham

We report the discovery of an Earth-sized planet (1.1±0.2 Earth Radii) in an 8.5-hour orbit around a late G-type star (KIC 8435766). The object was identified in a search for short-period planets in the Kepler database and confirmed to be a transiting planet (as opposed to an eclipsing stellar system) through the absence of ellipsoidal light variations or radial-velocity variations. The unusually short orbital period and the relative brightness of the host star (m_{Kep} = 11.5) enable robust detections of the changing illumination of the visible hemisphere of the planet, as well as the occultations of the planet by the star. We interpret these signals as representing a combination of reflected and reprocessed light, with the highest planet dayside temperatures in the range of 2300 K to 3100 K, and corresponding albedos of 0.6 to 0.2. Follow-up spectroscopy combined with shorter-cadence Kepler data will further pin down the system parameters and may even yield the mass of the planet.

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