Kepler-412 b
Astrophysical Synthesis & Habitability Characterization
Kepler-412 b is a confirmed gas giant exoplanet orbiting the star Kepler-412, located approximately 3542.8 light-years (1086.24 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 1.1465% across the stellar disk), this world measures 15.031 Earth radii (1.34 Jupiter radii) and has a measured mass of 299.078 Earth masses (0.94 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.49 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.32 g⊕ (12.94 m/s²), and an escape velocity of 49.9 km/s.
In its orbital architecture around Kepler-412, Kepler-412 b completes one full revolution every 1.721 Earth days at a semi-major axis of 0.02897 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 183.1 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.0038 (ranging from 0.0289 AU at periapsis to 0.0291 AU at apoapsis), the planet experiences minimal orbital distance variation.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1850 K (+1577°C / +2871°F) and receiving 2,144.31 S⊕ (~2,918,402 W/m²), Kepler-412 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-412 is classified as a solar-type yellow star of spectral type G3 V with an effective photospheric temperature of 5,750 K, a radius of 1.287 R☉, a mass of 1.167 M☉, an estimated bolometric luminosity of 1.624 L☉. Stellar evolution modeling indicates an estimated stellar age of 5.37 Gyr and a metallicity of [Fe/H] = 0.27 dex (metal-rich relative to the Sun). From Earth, Kepler-412 shines at apparent V-band magnitude 14.399 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.
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-412 |
| Spectral Type | G3 V |
| Effective Temp (Teff) | 5,750 K |
| Stellar Radius | 1.2870 R☉ |
| Stellar Mass | 1.1670 M☉ |
| Bolometric Luminosity | 1.624 L☉ |
| Metallicity [Fe/H] | 0.270 dex |
| Stellar Age | 5.370 Gyr |
| Apparent Magnitude | V: 14.399 · G: 14.249 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.028970 AU |
| Orbital Period | 1.721 days |
| Mean Orbital Velocity | 183.1 km/s |
| Orbital Eccentricity (e) | 0.00380 |
| Orbital Inclination (i) | 80.5590° |
| Mean Bulk Density | 0.49 g/cm³ (49.9 km/s vesc) |
| Insolation Flux | 2144.3070 S⊕ (~2,918,402 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 3542.800 LY (1086.240 pc) |