Kepler-131 c
Astrophysical Synthesis & Habitability Characterization
Kepler-131 c is a confirmed terrestrial exoplanet orbiting the star Kepler-131, located approximately 745.8 light-years (228.68 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0056% across the stellar disk), this world measures 0.84 Earth radii and has a measured mass of 8.25 Earth masses. Combining its mass and radius yields a mean bulk density of 76.75 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 11.69 g⊕ (114.64 m/s²), and an escape velocity of 35.1 km/s.
In its orbital architecture around Kepler-131, Kepler-131 c completes one full revolution every 25.517 Earth days at a semi-major axis of 0.17391 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 74.1 km/s (compared to Earth's 29.8 km/s). The orbit is modeled as circular (e = 0.00), maintaining a constant stellar distance throughout its year.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 615 K (+342°C / +648°F) and receiving 35.74 S⊕ (~48,637 W/m²), Kepler-131 c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-131 is classified as a stellar host with an effective photospheric temperature of 5,685 K, a radius of 1.03 R☉, a mass of 1.02 M☉, an estimated bolometric luminosity of 0.994 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.66 Gyr and a metallicity of [Fe/H] = 0.12 dex (metal-rich relative to the Sun). From Earth, Kepler-131 shines at apparent V-band magnitude 11.493 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-131 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-131 c sharing its stellar neighborhood alongside Kepler-131 b.
Methodology: Computed using the Schulze-Makuch et al. (2011) weighted metric comparing physical interior (radius, estimated density) and surface thermal regime (escape velocity, equilibrium temperature).
Discovery Facility: Kepler · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Kepler-131 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,685 K |
| Stellar Radius | 1.0300 R☉ |
| Stellar Mass | 1.0200 M☉ |
| Bolometric Luminosity | 0.994 L☉ |
| Metallicity [Fe/H] | 0.120 dex |
| Stellar Age | 3.660 Gyr |
| Apparent Magnitude | V: 11.493 · G: 11.490 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.173910 AU |
| Orbital Period | 25.517 days |
| Mean Orbital Velocity | 74.1 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.5300° |
| Mean Bulk Density | 76.75 g/cm³ (35.1 km/s vesc) |
| Insolation Flux | 35.7360 S⊕ (~48,637 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 745.800 LY (228.678 pc) |