HD 11964 c

HD 11964 c is an extrasolar planet approximately 110 light-years away in the constellation of Cetus. The planet was discovered in a close-orbit around the yellow subgiant star HD 11964. The planet has a minimum mass 35 times the mass of Earth and is located in a mildly eccentric orbit which takes almost 38 days to complete. HD 11964 c was a possible planet discovered on the same day as HD 11964 b in 2005. HD 11964 c was first proposed in a paper published in 2007,^[2] and finally confirmed with new data presented in a review of multi-planet systems which appeared on the arXiv preprint website in 2008.^[1]

HD 11964 c

Discovery
Discovered by	Butler et al.
Discovery site	California, United States
Discovery date	5 August 2005 Confirmed 27 May 2007
Detection method	Doppler spectroscopy
Orbital characteristics
Semi-major axis	0.229 AU (34,300,000 km)[1]
Eccentricity	0.15[1]
Orbital period (sidereal)	37.82[1] d
Time of periastron	2,454,370 ± 380[1]
Argument of periastron	102[1]
Semi-amplitude	4.65 ± 0.59[1]
Star	HD 11964

Some sources have used the designation "HD 11964 b" for this planet,^[3][4] however in their review of the properties of multi-planet extrasolar planetary systems, the discovery team has stated that the correct designation for this planet is HD 11964 c and the reversed system was due to confusion related to private communications between various groups of astronomers.^[1]