Description: Ross 128 b is a confirmed Earth-sized exoplanet, likely rocky, that is orbiting near the inner edge of the habitable zone of the red dwarf star Ross 128, at a distance of 11.007 light-years from Earth in the constellation of Virgo. The exoplanet was found using a decade's worth of radial velocity data using the European Southern Observatory's HARPS spectrograph at the La Silla Observatory in Chile. Ross 128 b is the nearest exoplanet around a quiet red dwarf, and is considered one of the best candidates for habitability. The planet is only 35% more massive than Earth, receives only 38% more starlight, and is expected to be a temperature suitable for liquid water to exist on the surface, if it has an atmosphere.
Mass (Jupiter mass): Unknown
Radius (Jupiter radius): 0.099 RJ
Density: 5.63 g/cm³
Equilibrium Temperature: 301.0 K
Orbital Period: 9.8658 days
Semi-major Axis: 0.0496 AU
Eccentricity: 0.116
Inclination: Unknown
Host Star: Ross 128
Spectral Type: M4
Temperature: 3192.0 K
Stellar Mass: 0.17 M☉
Stellar Radius: 0.21 R☉
Planet Letter: b
Object ID: 3.12086
Host ID: 2.56507
Discovery Date: 2018-05
Discovery Year: 2017
Discovery Method: Radial Velocity
Discovery Locale: Ground
Discovery Facility: La Silla Observatory
Discovery Instrument: HARPS Spectrograph