the 5-planet solution for the 55 Cancri system, the orbit of 55 Cancri c is mildly eccentric: at apoastron the planet is about 19% further from the star than it is at periastron. It is located closer to 55 Cancri A than Mercury is to the Sun, though it has a longer orbital period than the hot Jupiters. The planet is located close to a 3:1 resonance with the inner planet 55 Cancri b; however, simulations indicate that the two planets are not actually in this resonance. A limitation of the radial velocity method used to discover the planet is that only a lower limit on the mass can be obtained. Further astrometric observations with the Hubble Space Telescope on the outer planet 55 Cancri d suggest that planet is inclined at 53° to the plane of the sky; but innermost b and e are inclined at 85°. Planet c's inclination is unknown. Characteristics Since the planet was detected indirectly through observations of its star, properties such as its radius, composition, and temperature are unknown. With a mass similar to that of Saturn, 55 Cancri c is likely to be a gas giant without a solid surface. See also Appearance of extrasolar planets Cancer (Chinese astronomy) Lists of exoplanets Gliese 1132 b, Rocky exoplanet with a confirmed atmosphere. Mu Arae c, At constellation Ara Planetary system References External links 55 Cancri Cancer (constellation) Exoplanets discovered in 2002 Giant planets Exoplanets detected by radial velocity Exoplanets with proper names