Kepler-712 c
Astrophysical Synthesis & Habitability Characterization
Kepler-712 c is a confirmed sub-neptune exoplanet orbiting the star Kepler-712, located approximately 2845.7 light-years (872.49 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.325% across the stellar disk), this world measures 4.85 Earth radii (0.43 Jupiter radii) and has a measured mass of 21 Earth masses. Combining its mass and radius yields a mean bulk density of 1.01 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.89 g⊕ (8.73 m/s²), and an escape velocity of 23.3 km/s.
In its orbital architecture around Kepler-712, Kepler-712 c completes one full revolution every 226.89 Earth days at a semi-major axis of 0.66479 AU (situated at an orbital separation between Mercury's 0.39 AU and Venus's 0.72 AU). Its mean orbital velocity is approximately 31.9 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.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 4.850 R⊕, Kepler-712 c exceeds the empirical ~1.8–2.2 R⊕ Fulton radius valley threshold, indicating a substantial hydrogen-helium or supercritical volatile envelope without a conventional solid terrestrial surface.
The host star Kepler-712 is classified as a stellar host with an effective photospheric temperature of 5,148 K, a radius of 0.78 R☉, a mass of 0.84 M☉, an estimated bolometric luminosity of 0.383 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.31 Gyr and a metallicity of [Fe/H] = -0.03 dex (near-solar heavy-element abundance). From Earth, Kepler-712 shines at apparent V-band magnitude 16.161 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-712 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-712 c sharing its stellar neighborhood alongside Kepler-712 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-712 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,148 K |
| Stellar Radius | 0.7800 R☉ |
| Stellar Mass | 0.8400 M☉ |
| Bolometric Luminosity | 0.383 L☉ |
| Metallicity [Fe/H] | -0.030 dex |
| Stellar Age | 3.310 Gyr |
| Apparent Magnitude | V: 16.161 · G: 15.854 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.664790 AU |
| Orbital Period | 226.89 days |
| Mean Orbital Velocity | 31.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.7600° |
| Mean Bulk Density | 1.01 g/cm³ (23.3 km/s vesc) |
| Insolation Flux | 0.6620 S⊕ (~901 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2845.700 LY (872.493 pc) |