Gliese 674

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**Gliese 674**
Observation data Epoch J2000
Constellation (pronunciation)	Ara
Right ascension	17h 28m 39.95s
Declination	−46° 53′ 42.7″
Apparent magnitude (V)	9.38
Characteristics
Spectral type	M3 V
U-B color index	1.22
B-V color index	1.55
Astrometry
Radial velocity (R_v)	-10.5 km/s
Proper motion (μ)	RA: 573.32 mas/yr Dec.: -879.84 mas/yr
Parallax (π)	220.25 ± 1.59 mas
Distance	14.8 ± 0.1 ly (4.54 ± 0.03 pc)
Absolute magnitude (M_V)	11.06
Details
Mass	0.36 M_☉
Radius	0.41-43 R_☉
Luminosity	0.0032 L_☉
Temperature	? K
Metallicity	?
Rotation	?
Age	? years
Other designations
GJ 674, CD -46°11540, CP(D) −46°8664, GCTP 3958.00, LHS 449, LFT 1351, LTT 6942, LPM 645, HIP 85523.

Gliese 674 is a red dwarf star. It is located relatively near our Sun, at a distance of about 15 light years, in the constellation Ara.

[edit] Gliese 674 b

**Gliese 674 b**
Orbital elements
Extrasolar planet		List of extrasolar planets
Semimajor axis	(a)	0.039 AU
Eccentricity	(e)	0.2 ± 0.02
Orbital period	(P)	4.6938 ± 0.007 d
Angular distance	(θ)	8.59 mas
Longitude of periastron	(ω)	6 ± 200°
Time of periastron	(T₀)	2453780.085 ± 0.078 JD
Semi-amplitude	(K)	8.70 ± 0.19 m/s
Physical characteristics
Mass	(m)	>0.037 M_J (>11.8 M_⊕)
Discovery information
Discovery date		January 7, 2007
Discoverer(s)		Bonfils et al.
Detection method		HARPS
Discovery status		Published

Gliese 674 b is a planet that orbits tightly around Gliese 674. It is a sub-Neptune-or-Uranus-mass planet either gaseous or rocky. It orbits as close as 0.039 AU from the star and takes only 4.6938 days to orbit. This planet has a similar eccentricity to Mercury (e=0.2). The discovery of the planet was announced on January 7, 2007 by using the HARPS spectrograph mounted on the ESO’s 3.6 meter telescope at La Silla, Chile.