We report the discovery of K2-287b , a Saturn mass planet orbiting a G-dwarf with a period of P \approx 15 days .
First uncovered as a candidate using K2 campaign 15 data , follow-up photometry and spectroscopy were used to determine a mass of { M _ { P } } = 0.317 \pm 0.026 { M _ { J } } , radius { R _ { P } } = 0.833 \pm 0.013 { R _ { J } } , period P = 14.893291 \pm 0.000025 days and eccentricity e = 0.476 \pm 0.026 .
The host star is a metal-rich V = 11.410 \pm 0.129 mag G dwarf for which we estimate a mass { M } _ { \star } = 1.056 _ { -0.021 } ^ { +0.022 } { M } _ { \odot } , radius { R } _ { \star } = 1.070 \pm 0.010 { R } _ { \odot } , metallicity [ Fe/H ] = 0.20 \pm 0.05 and T _ { eff } = 5673 \pm 75 K. This warm eccentric planet with a time-averaged equilibrium temperature of T _ { eq } \approx 800 K adds to the small sample of giant planets orbiting nearby stars whose structure is not expected to be affected by stellar irradiation .
Follow-up studies on the K2-287 system could help in constraining theories of migration of planets in close-in orbits .