Ross 128 b

Ross 128 b Image

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.

Physical Properties

Mass (Jupiter mass): Unknown

Radius (Jupiter radius): 0.099 RJ

Density: 5.63 g/cm³

Equilibrium Temperature: 301.0 K

Orbital Parameters

Orbital Period: 9.8658 days

Semi-major Axis: 0.0496 AU

Eccentricity: 0.116

Inclination: Unknown

Host Star Properties

Host Star: Ross 128

Spectral Type: M4

Temperature: 3192.0 K

Stellar Mass: 0.17 M

Stellar Radius: 0.21 R

Discovery Information

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

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