82 Eridani

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**82 Eridani**
Observation data Equinox J2000
Constellation	Eridanus
Right ascension	03^h 19^m 55.6505^s
Declination	-43° 04′ 11.221″
Apparent magnitude (V)	4.27
Characteristics
Spectral type	G8V
U-B color index	0.22
B-V color index	0.70
Variable type	None
Astrometry
Radial velocity (R_v)	+87.3 km/s
Proper motion (μ)	RA: 3037.21 mas/yr Dec.: 726.52 mas/yr
Parallax (π)	165.00 ± 0.55 mas
Distance	19.77 ± 0.07 ly (6.06 ± 0.02 pc)
Absolute magnitude (M_V)	5.35
Details
Mass	0.97 M_☉
Radius	0.92 R_☉
Luminosity	0.60 L_☉
Temperature	5305 K
Metallicity	>29% Sun
Rotation	?
Age	1.0 × 10¹⁰ years
Other designations
e Eri, HD 20794, CD -43° 1028, GCTP 703, GJ 139, LHS 19, LTT 1583, HR 1008, SAO 216263, FK5 119, and HIP 15510.
Database references
SIMBAD	data
ARICNS	data

82 Eridani is a star about 20.2 light years away from Earth. It is in constellation Eridanus. It is a main sequence star of spectral type G5.

82 G. Eridani (often abbreviated "82 Eridani") is the 82nd star in Eridanus in the now-obscure catalog Uranometria Argentina. The Argentina catalog, compiled by the 19th century astronomer Benjamin Gould, is a southern-hemisphere analog of the more famous Flamsteed catalog, and used a similar numbering scheme. 82 G. Eridani is one of the very few "G." stars still referred to as such.

In terms of luminosity, 82 G. Eridani is marginally dimmer than the Sun, about half as luminous as Tau Ceti or Alpha Centauri B. 82 G. Eridani is a high-velocity star -- it is moving relatively quickly compared to the average -- and hence is probably a member of Population II, generally older stars whose motions take them well outside the plane of the Milky Way. Like many other Population II stars, 82 G. Eridani is somewhat metal-deficient (though much less deficient than many), and is older than the Sun.

In his book Habitable Planets for Man,^[1] Stephen Dole gave 82 G. Eridani his highest estimate for habitability: 5.7%. Four other stars had this figure: Alpha Centauri B, 70 Ophiuchi A, Eta Cassiopeiae A, and Delta Pavonis.