Two new candidate planets in eccentric orbits

Doppler measurements of two G-type main-sequence stars, HD 210277 and HD 16 8443, reveal Keplerian variations that imply the presence of companions wit h masses (M sin i) of 1.28 and 5.04 M-J (where M, is the mass of Jupiter) a nd orbital periods of 437 and 58 days, respectively. The orbits have large eccentricities of e = 0.45 and e = 0.54, respectively. All nine known extra solar planet candidates with a = 0.2-2.5 AU have orbital eccentricities gre ater than 0.1, higher than that of Jupiter (e = 0.05). Eccentric orbits may result from gravitational perturbations imposed by other orbiting planets or stars, by passing stars in the dense star-forming cluster, or by the pro toplanetary disk. Based on published studies and our near-IR adaptive optic s images, HD 210277 appears to be a single star. However, HD 168443 exhibit s a long-term velocity trend consistent with a close stellar companion, as yet undetected directly.