Kepler-131 b
Astrophysical Synthesis & Habitability Characterization
Kepler-131 b is a confirmed sub-neptune 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 0.046% across the stellar disk), this world measures 2.41 Earth radii and has a measured mass of 16.13 Earth masses. Combining its mass and radius yields a mean bulk density of 6.35 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 2.78 g⊕ (27.26 m/s²), and an escape velocity of 28.9 km/s.
In its orbital architecture around Kepler-131, Kepler-131 b completes one full revolution every 16.092 Earth days at a semi-major axis of 0.12789 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 86.5 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 718 K (+445°C / +833°F) and receiving 66.12 S⊕ (~89,992 W/m²), Kepler-131 b 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 b sharing its stellar neighborhood alongside Kepler-131 c.
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) | 0.127890 AU |
| Orbital Period | 16.092 days |
| Mean Orbital Velocity | 86.5 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.1400° |
| Mean Bulk Density | 6.35 g/cm³ (28.9 km/s vesc) |
| Insolation Flux | 66.1220 S⊕ (~89,992 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 745.800 LY (228.678 pc) |