Kepler-267 c
Astrophysical Synthesis & Habitability Characterization
Kepler-267 c is a confirmed sub-neptune exoplanet orbiting the star Kepler-267, located approximately 864.3 light-years (264.99 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.1238% across the stellar disk), this world measures 2.13 Earth radii and has a measured mass of 5.18 Earth masses. Combining its mass and radius yields a mean bulk density of 2.96 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.14 g⊕ (11.18 m/s²), and an escape velocity of 17.4 km/s.
In its orbital architecture around Kepler-267, Kepler-267 c completes one full revolution every 6.877 Earth days at a semi-major axis of 0.06 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 94.9 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 484 K (+211°C / +412°F) and receiving 17.58 S⊕ (~23,930 W/m²), Kepler-267 c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-267 is classified as a low-mass red dwarf of spectral type M1 V with an effective photospheric temperature of 4,258 K, a radius of 0.555 R☉, a mass of 0.5416 M☉, an estimated bolometric luminosity of 0.091 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.06 Gyr and a metallicity of [Fe/H] = -0.18 dex (metal-poor relative to the Sun). From Earth, Kepler-267 shines at apparent V-band magnitude 16.69 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-267 system is a multi-planet architecture hosting 3 confirmed worlds, with Kepler-267 c sharing its stellar neighborhood alongside Kepler-267 b, Kepler-267 d.
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-267 |
| Spectral Type | M1 V |
| Effective Temp (Teff) | 4,258 K |
| Stellar Radius | 0.5550 R☉ |
| Stellar Mass | 0.5416 M☉ |
| Bolometric Luminosity | 0.091 L☉ |
| Metallicity [Fe/H] | -0.180 dex |
| Stellar Age | 3.060 Gyr |
| Apparent Magnitude | V: 16.690 · G: 15.469 |
| System Architecture | 1 Star, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.060000 AU |
| Orbital Period | 6.877 days |
| Mean Orbital Velocity | 94.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 88.2600° |
| Mean Bulk Density | 2.96 g/cm³ (17.4 km/s vesc) |
| Insolation Flux | 17.5830 S⊕ (~23,930 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 864.300 LY (264.993 pc) |