23 Librae c

23 Librae c

Exoplanet		List of exoplanets
Parent star
Star		23 Librae
Constellation		Libra
Right ascension	(α)	15h 13m 28s
Declination	(δ)	–25° 18′ 33″
Apparent magnitude	(mV)	6.45
Distance		83.7 ly (25.6 pc)
Spectral type		G5V
Mass	(m)	1.05 M☉
Radius	(r)	1.2 R☉
Temperature	(T)	5559 K
Metallicity	[Fe/H]	0.23
Age		7.32 Gyr
Orbital elements
Semi-major axis	(a)	5.8 ± 0.5 AU (870 ± 75 Gm)
Periastron	(q)	5.1 AU (770 Gm)
Apastron	(Q)	6.5 AU (149 Gm)
Eccentricity	(e)	0.12 ± 0.02
Orbital period	(P)	5000 ± 400 d (14 ± 1 y)
Orbital speed	(υ)	12 km/s
Argument of periastron	(ω)	195 ± 48°
Time of periastron	(T0)	2,461,100 ± 600 JD
Physical characteristics
Minimum mass	(m sin i)	0.82 ± 0.03 MJ
Discovery information
Discovery date		December 14, 2009
Discoverer(s)		Jones et al.
Discovery method		Radial velocity
Discovery site		Keck Observatory
Discovery status		Published
Other designations
HD 134987 c
Database references
Extrasolar Planets Encyclopaedia		data
SIMBAD		data
Exoplanet Archive		data
Open Exoplanet Catalogue		data

23 Librae c (23 Lib c) is an extrasolar planet like Jupiter discovered in 2009 orbiting the star 23 Librae. It has one of the longest known orbits of a planet detected via radial velocity. The actual orbital period of this planet range from 4600 to 5400 days (from 12.5 to 15 years). The reason the error range for orbital period is so large is because this planet did not complete the orbit during the time of continuous observations. Using the range of orbital periods, this planet's average distance would sit between 5.3 and 6.3 AU, or between 491 and 584 Mmi (millions of miles).