HD 118203 b

HD 118203 b

Exoplanet		List of exoplanets
Parent star
Star		HD 118203
Constellation		Ursa Major
Right ascension	(α)	13h 34m 02.5375s
Declination	(δ)	+53° 43′ 42.704″
Distance		289 ly (88.6 pc)
Spectral type		K0IV
Orbital elements
Semi-major axis	(a)	0.07 AU
Periastron	(q)	0.048 AU
Apastron	(Q)	0.092 AU
Eccentricity	(e)	0.309 ± 0.014
Orbital period	(P)	6.1335 ± 0.0006 d (0.016792 y)
Orbital speed	(υ)	120 km/s
Argument of periastron	(ω)	155.7 ± 2.4°
Time of periastron	(T0)	2453394.23 ± 0.3 JD
Semi-amplitude	(K)	217 ± 3 m/s
Physical characteristics
Mass	(m)	>2.14 MJ (>680 M⊕)
Discovery information
Discovery date		22 August 2005
Discoverer(s)		Da Silva et al.
Discovery method		Doppler spectroscopy (ELDOIE)
Discovery site		Haute-Provence Observatory, France
Discovery status		Published
Other designations
HIP 66192 b
Database references
Extrasolar Planets Encyclopaedia		data
SIMBAD		data
Exoplanet Archive		data
Open Exoplanet Catalogue		data

HD 118203 b is a jovian planet that takes only 6.13 days or 147 hours to orbit the parent star at a distance of 0.07 astronomical units. It has minimum mass of 2.14 times that of Jupiter but the true mass is not known since inclination is not known. This hot Jupiter is unusual since it has relatively high eccentricity of 0.31.

HD 118203 b was discovered in August 2005 in Haute-Provence Observatory in France by Da Silva who used the doppler spectroscopy to look for shifts in the star’s spectrum caused by the planet’s gravity as the planet orbits the star.