Lecturer: Dr. Avi Shporer Affiliation: California Institute of Technology (CALTECH) Abstract: We are living in the golden age of time series photometry, when high-quality data is delivered by space-based surveys for a large number of stars in visible light. This enables a detailed study of the minute variability following the orbital motion of stellar binaries and star-planet systems, at a precision which is beyond reach from the ground. These orbital modulations are induced by a combination of gravitational and atmospheric processes, hence the phase curve shape contains information about the companion’s mass and atmospheric characteristics. I will present the science I am doing with phase curves. This includes using phase curve variability to detect non- eclipsing systems, which can transform photometric surveys like Kepler to the equivalent of a radial velocity survey. Another important application is the mass measurement of hot Jupiters orbiting hot early-type stars, where the mass cannot be measured using radial velocities. In addition, using phase curves of transiting hot Jupiters I showed that the atmospheres of most such exoplanets have their optical brightest region shifted Westward of the substellar point, indicating an inhomogeneous cloud coverage. Finally, I will present a Keck/HIRES project focused on high-eccentricity binary stars identified in Kepler phase curves (aka heartbeat stars). As a whole, the above shows the high scientific potential of the study of space-based phase curves, which we have only begun to explore in recent years and will continue using data from current and future space- based surveys including K2, TESS, and PLATO. Additional details of the upcoming Astrophysics' seminars can be found on the following link. ‏האירוע הזה כולל שיחת וידאו ב-Google Hangouts. הצטרף: https://plus.google.com/hangouts/_/mail.huji.ac.il/special?hceid=bWFpbC5odWppLmFjLmlsX2c0czhydDlpcmhwZzRvdGNybWIzZGFqcjdvQGdyb3VwLmNhbGVuZGFyLmdvb2dsZS5jb20.5aqdvd42afgn27c390je3o8268&hs=121