GJ 581 b
Description: Gliese 581b or Gl 581b is an exoplanet orbiting within the Gliese 581 system, located 20.5 light-years away from Earth in the Libra constellation. It is the first planet discovered of three confirmed in the system so far, and the second in order from the star.
Physical Properties
Mass (Jupiter mass): 0.0645002131606191 MJ
Radius (Jupiter radius): 0.427 RJ
Density: 1.02 g/cm³
Equilibrium Temperature: Unknown
Orbital Parameters
Orbital Period: 5.3686 days
Semi-major Axis: 0.0399 AU
Eccentricity: 0.0342
Inclination: 47.0°
Host Star Properties
Host Star: GJ 581
Spectral Type: M3.0 V
Temperature: 3500.0 K
Stellar Mass: 0.3 M☉
Stellar Radius: 0.3 R☉
Discovery Information
Planet Letter: b
Object ID: 3.10983
Host ID: 2.57422
Discovery Date: 2005-12
Discovery Year: 2005
Discovery Method: Radial Velocity
Discovery Locale: Ground
Discovery Facility: La Silla Observatory
Discovery Instrument: HARPS Spectrograph