Kepler-432 b
Astrophysical Synthesis & Habitability Characterization
Kepler-432 b is a confirmed gas giant exoplanet orbiting the star Kepler-432, located approximately 2765.9 light-years (848.02 parsecs) from the Solar System. First announced in 2015 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.084% across the stellar disk), this world measures 12.834 Earth radii (1.14 Jupiter radii) and has a measured mass of 1719.46 Earth masses (5.41 Jupiter masses). Combining its mass and radius yields a mean bulk density of 4.49 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 10.44 g⊕ (102.38 m/s²), and an escape velocity of 129.5 km/s.
In its orbital architecture around Kepler-432, Kepler-432 b completes one full revolution every 52.501 Earth days at a semi-major axis of 0.301 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 62.4 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.5134, swinging from 0.1465 AU at periapsis out to 0.4555 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 812 K (+539°C / +1002°F) and receiving 97.85 S⊕ (~133,168 W/m²), Kepler-432 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-432 is classified as a stellar host with an effective photospheric temperature of 4,995 K, a radius of 4.06 R☉, a mass of 1.32 M☉, an estimated bolometric luminosity of 9.206 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.2 Gyr and a metallicity of [Fe/H] = -0.07 dex (near-solar heavy-element abundance). From Earth, Kepler-432 shines at apparent V-band magnitude 12.398 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-432 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-432 b sharing its stellar neighborhood alongside Kepler-432 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-432 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,995 K |
| Stellar Radius | 4.0600 R☉ |
| Stellar Mass | 1.3200 M☉ |
| Bolometric Luminosity | 9.206 L☉ |
| Metallicity [Fe/H] | -0.070 dex |
| Stellar Age | 4.200 Gyr |
| Apparent Magnitude | V: 12.398 · G: 12.182 |
| System Architecture | 2 Stars, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.301000 AU |
| Orbital Period | 52.501 days |
| Mean Orbital Velocity | 62.4 km/s |
| Orbital Eccentricity (e) | 0.51340 |
| Orbital Inclination (i) | 88.1700° |
| Mean Bulk Density | 4.49 g/cm³ (129.5 km/s vesc) |
| Insolation Flux | 97.8460 S⊕ (~133,168 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2765.900 LY (848.023 pc) |