Rho Coronae Borealis is a star similar to the Sun but of greater age, around which has been found a planet marginally more massive than Jupiter. This epistellar Jovian, the fourth of its type to be discovered, occupies a nearly circular, sub-Mercurian orbit around its host.

 

Host star
Distance	55 light-years (16.7 pc)
Spectral type	G0 V or G2 V
Temperature	5,480°C (5,750 K)
Luminosity (Sun = 1)	1.8
Mass (Sun = 1)	0.89
Apparent magnitude	5.4

 

Planet
Mass (Jupiter = 1)	1.13
Semi-major axis	0.25 AU (37.5 million km, 23.3 million mi.)
Orbital period	39.65 days
Eccentricity	0.028
Year of discovery	1997
Discoverer	Robert Noyes et al (AFOE)
Method of discovery	radial velocity

 

Reference

1. Noyes, R., et al. "A Planet Orbiting the Star Rho Coronae Borealis," Astrophysical Journal, 483, 111 (1997).