Kepler-1312 c
Astrophysical Synthesis & Habitability Characterization
Kepler-1312 c is a confirmed terrestrial exoplanet orbiting the star Kepler-1312, located approximately 975.5 light-years (299.1 parsecs) from the Solar System. First announced in 2021 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0108% across the stellar disk), this world measures 1.027 Earth radii and has a measured mass of 1.07 Earth masses. Combining its mass and radius yields a mean bulk density of 5.45 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.01 g⊕ (9.9 m/s²), and an escape velocity of 11.4 km/s.
In its orbital architecture around Kepler-1312, Kepler-1312 c completes one full revolution every 1.116 Earth days at a semi-major axis of 0.02103 AU (an ultra-close orbit less than one-seventh of Mercury's 0.387 AU distance from the Sun, where strong stellar tidal forces typically induce synchronous rotation). Its mean orbital velocity is approximately 205 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 1659 K (+1386°C / +2527°F) and receiving 1,770.20 S⊕ (~2,409,242 W/m²), Kepler-1312 c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-1312 is classified as a stellar host with an effective photospheric temperature of 5,721 K, a radius of 0.905 R☉, a mass of 0.983 M☉, an estimated bolometric luminosity of 0.787 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.89 Gyr and a metallicity of [Fe/H] = 0.02 dex (near-solar heavy-element abundance). From Earth, Kepler-1312 shines at apparent V-band magnitude 12.491 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-1312 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-1312 c sharing its stellar neighborhood alongside Kepler-1312 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-1312 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,721 K |
| Stellar Radius | 0.9050 R☉ |
| Stellar Mass | 0.9830 M☉ |
| Bolometric Luminosity | 0.787 L☉ |
| Metallicity [Fe/H] | 0.020 dex |
| Stellar Age | 0.890 Gyr |
| Apparent Magnitude | V: 12.491 · G: 12.378 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.021030 AU |
| Orbital Period | 1.116 days |
| Mean Orbital Velocity | 205 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 82.6400° |
| Mean Bulk Density | 5.45 g/cm³ (11.4 km/s vesc) |
| Insolation Flux | 1770.2000 S⊕ (~2,409,242 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 975.500 LY (299.104 pc) |