HR 8799 c

HR 8799 c is an extrasolar planet located approximately 129 light-years away in the constellation of Pegasus, orbiting the 6th magnitude Lambda Boötis star HR 8799. This planet has a mass between 5 and 10 Jupiter masses and a radius from 20 to 30% larger than Jupiter's. It orbits at 38 AU from HR 8799 with an unknown eccentricity and a period of 190 years; it is the 2nd planet discovered in the HR 8799 system. Along with two other planets orbiting HR 8799, this planet was discovered on November 13, 2008, by Marois et al., using the Keck and the Gemini observatories in Hawaii. These planets were discovered using the direct imaging technique. In January 2010, HR 8799 c became the 9th exoplanet candidate to have a portion of its spectrum directly observed (following 2M1207b, DH Tau b, GQ Lup b, AB Pic b, CHXR 73 b, HD 203030 b, CT Cha b and 1RXS J1609b), confirming the feasibility of direct spectrographic studies of exoplanets.