Variability of Exoplanetary Secondary Eclipse

Phase curves and secondary eclipses of gaseous exoplanets are diagnostic of not only atmospheric composition and meteorology, but variations in the phase curves and eclipses over time may point to variability driven by atmospheric dynamics. The dataset from NASA’s Kepler Mission has accurate photometric precision and spans a period of over 1,000 days, providing an ideal dataset to study Kepler-76 b. Kepler-76 b is a 2 Jupiter-mass gas giant, with an equilibrium temperature approaching 2,000 K, in a 1.5-day orbit around its star, and the data reveal Kepler-76 b's secondary eclipse - with a depth of 87±6 parts-per-million (ppm), which corresponds to an effective temperature of 2,830 K. The data also reveals variations in the phase curve for Kepler 76-b secondary eclipse, with an average value of 50.5 ppm and values ranging from 35 ppm to 70 ppm over tens of days.