Barnard's Star c
Planet· orbits the Sun
Barnard's Star c — a sub-Earth world (minimum mass ~0.34 Earth) on a 4.1-day orbit, one of a compact family of four. Too hot for liquid water; never imaged.
Open in 3D viewSee Barnard's Star c in the live, interactive 3D map
Key facts
Minimum mass
2.00 × 10²⁴ kg
0.335 M⊕
Year
4.12 Earth days
Distance from Barnard's Star
4,098,982 km
Science
Physical
- Minimum mass (m·sin i)
- 2.00 × 10²⁴ kg · 0.335 M⊕
- Radius
- Not measured
Orbital
- Semi-major axis
- 4,098,982 km
- Eccentricity
- 0.08
- Inclination
- 0.00 °
- Orbital period
- 4.1 days
- Perihelion
- 3,771,063 km
- Aphelion
- 4,426,900 km
- Mean orbital velocity
- 72.3 km/s
Composition
- Bulk composition
- Presumed rocky (minimum mass ~0.34 Earth); never imaged.
- Surface appearance
- Appearance based on ESO/M. Kornmesser's artist's concept. No spacecraft has imaged this world, so its real appearance is unknown — The surface shown is an artistic representation, shown only in Vision mode; Realism shows a plain spectral colour.
Radiation & temperature
- Insolation
- 4.66 S⊕ · 4.66× the sunlight Earth receives
- Equilibrium temperature
- 400 K (127 °C)
Discovery & history
- Method
- Radial-velocity detection (stellar wobble)
- Name
- Designated 'c' as the second planet found around Barnard's Star, following the IAU convention of lettering planets in discovery order starting at 'b'.
Established in 2025 as ESO's ESPRESSO revealed that Barnard's Star hosts not one planet but a compact family of four sub-Earth worlds, all orbiting closer in than Mercury.
Images
Never imaged — this world is known only from the tiny gravitational tug it exerts on its star (radial velocity). An artist's impression of the whole system is on the system view; the planet's own appearance is unknown.