Kepler-212 b
Astrophysical Synthesis & Habitability Characterization
Kepler-212 b is a confirmed terrestrial exoplanet orbiting the star Kepler-212, located approximately 2241.3 light-years (687.19 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0047% across the stellar disk), this world measures 1.09 Earth radii and has a measured mass of 1.32 Earth masses. Combining its mass and radius yields a mean bulk density of 5.62 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.11 g⊕ (10.89 m/s²), and an escape velocity of 12.3 km/s.
In its orbital architecture around Kepler-212, Kepler-212 b completes one full revolution every 16.258 Earth days at a semi-major axis of 0.133 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 89 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 830 K (+557°C / +1035°F) and receiving 133.87 S⊕ (~182,192 W/m²), Kepler-212 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-212 is classified as a stellar host with an effective photospheric temperature of 5,852 K, a radius of 1.455 R☉, a mass of 1.166 M☉, an estimated bolometric luminosity of 2.228 L☉. Stellar evolution modeling indicates an estimated stellar age of 5.13 Gyr and a metallicity of [Fe/H] = 0.22 dex (metal-rich relative to the Sun). From Earth, Kepler-212 shines at apparent V-band magnitude 13.129 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-212 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-212 b sharing its stellar neighborhood alongside Kepler-212 c.
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-212 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,852 K |
| Stellar Radius | 1.4550 R☉ |
| Stellar Mass | 1.1660 M☉ |
| Bolometric Luminosity | 2.228 L☉ |
| Metallicity [Fe/H] | 0.220 dex |
| Stellar Age | 5.130 Gyr |
| Apparent Magnitude | V: 13.129 · G: 12.987 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.133000 AU |
| Orbital Period | 16.258 days |
| Mean Orbital Velocity | 89 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.6100° |
| Mean Bulk Density | 5.62 g/cm³ (12.3 km/s vesc) |
| Insolation Flux | 133.8660 S⊕ (~182,192 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2241.300 LY (687.194 pc) |