Gliese 445

Gliese 445 (Gl 445 or AC +79 3888) is an M-type main sequence star in the northern part of the constellation Camelopardalis.

Gliese 445

Image of AC +79 3888 (circled), also known as Gliese 445, located 17.1 light-years from Earth Credit: Caltech/Palomar
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Camelopardalis
Right ascension	11h 47m 41.3885s[1]
Declination	+78° 41′ 28.179″[1]
Apparent magnitude (V)	10.80[2]
Characteristics
Spectral type	M4.0Ve[3]
B−V color index	1.572[2]
Astrometry
Radial velocity (Rv)	−111.707[1] km/s
Proper motion (μ)	RA: 748.111[1] mas/yr Dec.: 480.804[1] mas/yr
Parallax (π)	190.3251±0.0194 mas[4]
Distance	17.137 ± 0.002 ly (5.2542 ± 0.0005 pc)
Absolute magnitude (MV)	12.227[5]
Details
Mass	0.14[6] M☉
Radius	0.285[5] R☉
Luminosity	0.008[7] L☉
Surface gravity (log g)	4.72[7] cgs
Temperature	3,507[1] K
Metallicity [Fe/H]	−0.30[5] dex
Rotational velocity (v sin i)	<2.5[8] km/s
Other designations
Gliese 445, Gl 445, G 254-29, AC+79 3888, HIP 57544, LFT 849, LHS 2459, LTT 13235, NLTT 28539, PLX 2722[9]
Database references
SIMBAD	data
ARICNS	data
Gliese 445 Location of Gliese 445 in the constellation Camelopardalis

Location

Distances of the nearest stars from 20,000 years ago until 80,000 years in the future

Gliese 445 is currently 17.1 light-years from Earth and has an apparent magnitude of 10.8. It is visible all night long from locations north of the Tropic of Cancer, but not to the naked eye.^[10] Because the star is a red dwarf with a mass only a quarter to a third of that of the Sun, scientists question the ability of this system to support life.^[10] Gliese 445 is also a known X-ray source.^[11]

The Voyager 1 probe will pass within 1.6 light-years of Gliese 445 in about 40,000 years.^[12]

Solar encounter

While the Voyager probe moves through space towards a 1.6-light-year minimum distance from Gliese 445, the star is rapidly approaching the Sun. At the time the probe passes Gliese 445, the star will be about 1.059 parsecs (3.45 light-years) from the Sun,^[13] but with less than half the brightness necessary to be seen with the naked eye.^[10] At that time, Gliese 445 will be approximately tied with Ross 248 for being the closest star to the Sun (see List of nearest stars and brown dwarfs#Distant future and past encounters).

See also

• Lists of stars