HD 139357

HD 139357

Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Draco
Right ascension	15h 35m 16.20s
Declination	+53° 55′ 19.7″
Apparent magnitude (V)	5.977
Characteristics
Spectral type	K4III
B−V color index	1.191
Astrometry
Radial velocity (Rv)	–8.75 ± 0.39 km/s
Proper motion (μ)	RA: -18.32 ± 0.30 mas/yr Dec.: 1.64 ± 0.33 mas/yr
Parallax (π)	8.47 ± 0.30 mas
Distance	390 ± 10 ly (118 ± 4 pc)
Absolute magnitude (MV)	0.557
Details
Mass	1.35 ± 0.24 M☉
Radius	11.47 ± 0.75 R☉
Luminosity	57.4 L☉
Surface gravity (log g)	1.51 cgs
Temperature	4700 ± 70 K
Metallicity	–0.13 ± 0.05
Age	3.07 ± 1.47 Gyr
Other designations
BD+54° 1756, GC 20977, GCRV 9003, HIP 76311, HR 5811, PPM 35043, SAO 29583
Database references
SIMBAD	data
Exoplanet Archive	data
Extrasolar Planets Encyclopaedia	data

HD 139357 is a 6th magnitude K-type giant star located approximately 390 light years from Earth, visible in the constellation Draco. Its mass is four thirds that of our Sun but its radius is 11.47 times larger. However, despite being a giant star, it is only 3.07 billion years old, which is younger than our Sun.

It hosts a planet discovered in 2009.

The HD 139357 planetary system

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	≥9.76 ± 2.15 MJ	2.36 ± 0.02	1125.7 ± 9	0.10 ± 0.02	—	—

See also

• 42 Draconis
• Iota Draconis
• List of extrasolar planets
• List of stars in Draco