Kepler's Exoplanet Legacy & the Passing of the Baton

Lecar Prize Lecture
April 6, 2017
Phillips Auditorium
NASA Ames Research Center

The scientific community recently celebrated two decades of exploring the diversity of planets and planetary systems orbiting main sequence stars. Today, the discoveries spill into the thousands, and the sensitivity boundaries continue to expand. NASA's Kepler Mission unveiled a galaxy replete with small planets including populations that don't exist in our own solar system. The final discovery catalog and the associated survey completeness and reliability metrics will be delivered this spring as Kepler (prime) heads toward mission closeout on September 30, 2017. The final data products are sufficient for computing planet occurrence rates as a function of size, orbital period, and host star properties. To date, we've learned that every late-type star has at least one planet, that terrestrial-sized planets are more common than giants within 1 AU, and that the nearest, potentially habitable earth-sized planet is likely within 5 pc.

After four years of continuous data collection, Kepler prime ceased observations of Cygnus/Lyra in May 2013 when a second reaction wheel failed. Thanks to innovative engineering, the spacecraft gained a second lease on life and emerged as the ecliptic surveyor, K2. In many regards, K2 is a distinctly new mission, not only by pointing at new areas of the sky but also by focusing on community-driven goals that diversify the science yield. For exoplanets, this means targeting bright (V < 13) and low mass (M dwarfs) stars -- the populations harboring planets amenable to dynamical and atmospheric characterization. To date, the mission has executed 12 observing campaigns lasting ~80 days each and has achieved a 6-hour photometric precision of 30 ppm. Nearly 150 new planets have been confirmed, including nearby (< 50 pc) systems on the watch-list for future observing campaigns with the James Webb Space Telescope.

While Kepler prime is setting the stage for the direct imaging missions of the future, K2 is easing us into an era of atmospheric characterization with TESS and JWST. We are ready to pass the baton to these future missions taking us one step closer toward finding evidence of life beyond the Solar System.