HD 82943

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**HD 82943**
Observation data Equinox 2000
Constellation	Hydra
Right ascension	09^h 34^m 50.736^s
Declination	−12° 07' 46.365"
Apparent magnitude (V)	6.54
Absolute magnitude (V)	4.35
Distance	89.56 ly (27.46 pc)
Spectral type	G0V
Other designations
BD-11°2670,HIP 47007

HD 82943 is a yellow dwarf star (spectral type G0) in the constellation of Hydra, 89.5 light years from our solar system. It is known to be orbited by at least two large extrasolar planets which are locked in a 2:1 orbital resonance.

1 Planets
- 1.1 HD 82943 c
- 1.2 HD 82943 b
2 References
3 External links

[edit] Planets

[edit] HD 82943 c

**HD 82943 c**
Orbital elements

Semi-major axis a:	0.75 AU
Eccentricity e:	0.38± 0.01
Orbital period P:	219.4 ± 0.2 d
Inclination i:	?°
Longitude of periastron ω:	124 ± 3°
Time of periastron τ:	2,452,284 ± 1 JD
Physical characteristics
Mass:	>1.85 M_J
Radius:	? R_J
Density:	? kg/m³
Temperature:	? K
Discovery
Discovery date:	2001
Detection method(s):
Discoverer(s):	Mayor, Udry et al.

HD 82943 c is a gas giant planet almost identical to HD 82943 b in size. It has an eccentric orbit that sometimes places it very close to the star, and sometimes within its habitable zone.

[edit] HD 82943 b

**HD 82943 b**
Orbital elements

Semi-major axis a:	1.18 AU
Eccentricity e:	0.18± 0.04
Orbital period P:	435.1 ± 1.4 d
Inclination i:	?°
Longitude of periastron ω:	237 ± 13°
Time of periastron τ:	2,451,758 ± 13 JD
Physical characteristics
Mass:	>1.84 M_J
Radius:	? R_J
Density:	? kg/m³
Temperature:	? K
Discovery
Discovery date:	2000
Detection method(s):
Discoverer(s):	Mayor, Udry et al.

HD 82943 b is a gas giant one and a half times the size of Jupiter. Its orbit is entirely within the star's habitable zone. This means that it might have large moons with atmospheres capable of harboring life.