Planet Hunters VII. Discovery of a New Low-Mass, Low-Density Planet (PH3 c) Orbiting Kepler-289 with Mass Measurements of Two Additional Planets (PH3 b and d)

Joseph R. Schmitt, Eric Agol, Katherine M. Deck +18

We report the discovery of one newly confirmed planet ($P=66.06$ days, $R_{\mathrm{P}}=2.68\pm 0.17R_{\oplus }$) and mass determinations of two previously validated Kepler planets, Kepler-…