Gliese 649

Gliese 649

Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Hercules
Right ascension	16h 58m 08.850s
Declination	25° 44′ 38.99″
Apparent magnitude (V)	9.62
Characteristics
Spectral type	M1.5V
Apparent magnitude (B)	11.21
Apparent magnitude (R)	8.8
Apparent magnitude (I)	8.0
Apparent magnitude (J)	6.448
Apparent magnitude (H)	5.865
Apparent magnitude (K)	5.624
B−V color index	1.496
V−R color index	0.8
R−I color index	0.8
Astrometry
Radial velocity (Rv)	6.4 km/s
Proper motion (μ)	RA: −114.07±0.95 mas/yr Dec.: −506.26±1.33 mas/yr
Parallax (π)	96.67 ± 1.39 mas
Distance	33.7 ± 0.5 ly (10.3 ± 0.1 pc)
Absolute magnitude (MV)	9.595
Details
Mass	0.54 M☉
Radius	0.52 R☉
Luminosity	0.045 L☉
Temperature	3733±20 K
Metallicity [Fe/H]	−0.04±0.17 dex
Age	0.48 Gyr
Other designations
HIP 83043, TYC 2063-00479-1, BD+25 3173, 2MASS J16580884+2544392
Database references
SIMBAD	data
Exoplanet Archive	data
ARICNS	data
Extrasolar Planets Encyclopaedia	data

Gliese 649 is a red dwarf star in the constellation of Hercules, located roughly 34 light years from the Sun. The star has been found to host an extrasolar planet.

A planetary companion

According to Johnson et al. (2010) a Saturn-mass planet has been detected around the red dwarf star. It yields 32.8% of Jupiter's mass and is located 1.15 astronomical units from its star in eccentric orbit (e=0.3). Assuming a luminosity of 4.5% that of the Sun, the habitable zone is located at 0.21 AUs, thus the planet should be as cold as if it were located at 5.5 AUs from a Solar-like star. Also accounting different periastron and apastron positions of 0.8 and 1.49 AUs respectively, the planet could likely show seasonal temperature changes.

The Gliese 649 planetary system

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	≥ 0.328±0.032 MJ	1.135±0.035	598.3±4.2	0.30±0.08	—	—

See also

• Gliese 317
• Gliese 849
• List of extrasolar planets