Proxima Cen b
A confirmed exoplanet orbiting Proxima Cen.
Compared with Earth
- Mass
- About 1.1 times Earth's mass.
- Temperature
- About -55 °C (-67 °F) from starlight alone, against -18 °C (-1 °F) for Earth measured the same way.
- Starlight
- About 64% of the starlight Earth gets from the Sun.
- Year
- A year here lasts about 11 Earth days.
Planet
- Radius
- Unknown
- Mass
- 1.055 × Earth
- Density
- Unknown
- Equilibrium temperature
- 218 K
- Starlight received
- 0.641 × Earth
- Orbital period
- 11.18 days
- Average distance from its star
- 0.04848 AU
Star
- Host star
- Proxima Cen
- Spectral class
- M — red dwarf
- Surface temperature
- 2,900 K
- Radius
- 0.141 × Sun
- Mass
- 0.1221 × Sun
- Age
- Unknown
System
- Distance from Earth
- 4.244 light-years (1.301 parsecs)
- Stars in system
- 3
- Known planets
- 2
Discovery
- Year
- 2016
- Method
- Radial Velocity
- Facility
- European Southern Observatory
Data from the NASA Exoplanet Archive, synced October 14, 2026.