Catalog of New K2 Exoplanet Candidates from Citizen Scientists

Abstract

The K2 mission has successfully found ≈1000 new exoplanet candidates.12 Now with an enormous data set (≈400,000 stellar targets) that nearly doubles the source count of Kepler (Huber et al. 2016), data parsing provides a unique time intensive obstacle. The Exoplanet Explorers13 project, part of the Zooniverse platform, allows citizen scientists to help overcome the abundance of transit data (Christiansen et al. 2018). We make available 204,855 statistically significant dips in K2 light curves from campaigns 0–8, 10, and 12–14. We used the k2phot pipeline (Petigura et al. 2018) to remove the K2 systematics and searched for periodic transits using the TERRA search algorithm (Petigura et al. 2013). For training, each participant is shown an example of a real folded exoplanet transit light curve, with the expected model plotted over the data. The volunteer is then instructed to look for dips that provide a similar match to this basic transit model. Each folded light curve presented are assigned a "Yes" or "No" value by the citizen scientist, indicating their belief that the source of the dip is caused by a transiting exoplanet. This simple visual inspection helps create a targeted search of the K2 light curves.