Gliese 638

Gliese 638
Observation data; Epoch J2000 Equinox J2000
Constellation	Hercules
Right ascension	16h 45m 06.3511s
Declination	+33° 30′ 33.226″
Apparent magnitude (V)	8.11
Characteristics
Spectral type	K7V
U−B color index	1.29
B−V color index	1.37
Variable type	Suspected
Astrometry
Radial velocity (Rv)	-29.6±0.9 km/s
Proper motion (μ)	RA: -39.18 mas/yr ; Dec.: 383.43 mas/yr
Parallax (π)	101.59 ± 0.23 mas
Distance	32.11 ± 0.07 ly ; (9.84 ± 0.02 pc)
Absolute magnitude (MV)	8.11
Other designations
	GJ 638, BD +33°2777, HD 151288, LTT 14967, SAO 65525, NSV 7951, HIP 82003.
Database references
SIMBAD	data

Gliese 638 is a main sequence star in the constellation of Hercules. It is located about 31.9 light years from the Earth. This is a suspected variable star with a measured apparent magnitude that ranges from 8.09–8.11.^[3] As a K-class star, it has a lower mass than the Sun, and consequently is less luminous.

References

^ Wilson, O. C. (1962). "Relationship between colors and spectra of late main-sequence stars". Astrophysical Journal. 136: 793–799. Bibcode:1962ApJ...136..793W. doi:10.1086/147437.
^ Holmberg, J.; et al. (July 2009), "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics", Astronomy and Astrophysics, 501 (3): 941–947, arXiv:0811.3982, Bibcode:2009A&A...501..941H, doi:10.1051/0004-6361/200811191, S2CID 118577511.
^ Kukarkin, B. V.; et al. (1981). Catalogue of suspected variable stars. Moscow, USSR: Academy of Sciences.