Kepler-279 c
Astrophysical Synthesis & Habitability Characterization
Kepler-279 c is a confirmed sub-neptune exoplanet orbiting the star Kepler-279, located approximately 3383.5 light-years (1037.4 parsecs) from the Solar System. First announced in 2013 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.1357% across the stellar disk), this world measures 4.3 Earth radii (0.38 Jupiter radii) and has a measured mass of 49.4 Earth masses (0.16 Jupiter masses). Combining its mass and radius yields a mean bulk density of 3.43 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 2.67 g⊕ (26.18 m/s²), and an escape velocity of 37.9 km/s.
In its orbital architecture around Kepler-279, Kepler-279 c completes one full revolution every 35.736 Earth days at a semi-major axis of 0.2236 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 68.1 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 774 K (+501°C / +934°F) and receiving 60.16 S⊕ (~81,874 W/m²), Kepler-279 c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-279 is classified as a stellar host with an effective photospheric temperature of 6,689 K, a radius of 1.07 R☉, a mass of 1.1 M☉, an estimated bolometric luminosity of 2.056 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.22 Gyr and a metallicity of [Fe/H] = -0.114 dex (metal-poor relative to the Sun). From Earth, Kepler-279 shines at apparent V-band magnitude 13.647 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-279 system is a multi-planet architecture hosting 4 confirmed worlds, with Kepler-279 c sharing its stellar neighborhood alongside Kepler-279 b, Kepler-279 d, Kepler-279 e.
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-279 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,689 K |
| Stellar Radius | 1.0700 R☉ |
| Stellar Mass | 1.1000 M☉ |
| Bolometric Luminosity | 2.056 L☉ |
| Metallicity [Fe/H] | -0.114 dex |
| Stellar Age | 0.220 Gyr |
| Apparent Magnitude | V: 13.647 · G: 13.585 |
| System Architecture | 1 Star, 4 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.223600 AU |
| Orbital Period | 35.736 days |
| Mean Orbital Velocity | 68.1 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 87.0900° |
| Mean Bulk Density | 3.43 g/cm³ (37.9 km/s vesc) |
| Insolation Flux | 60.1570 S⊕ (~81,874 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 3383.500 LY (1037.400 pc) |