Kepler-133 b
Astrophysical Synthesis & Habitability Characterization
Kepler-133 b is a confirmed super-earth exoplanet orbiting the star Kepler-133, located approximately 2131.8 light-years (653.6 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0128% across the stellar disk), this world measures 1.76 Earth radii and has a measured mass of 3.75 Earth masses. Combining its mass and radius yields a mean bulk density of 3.79 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.21 g⊕ (11.87 m/s²), and an escape velocity of 16.3 km/s.
In its orbital architecture around Kepler-133, Kepler-133 b completes one full revolution every 8.13 Earth days at a semi-major axis of 0.083 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 111.1 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 1041 K (+768°C / +1414°F) and receiving 408.58 S⊕ (~556,077 W/m²), Kepler-133 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-133 is classified as a stellar host with an effective photospheric temperature of 5,736 K, a radius of 1.425 R☉, a mass of 1.02 M☉, an estimated bolometric luminosity of 1.972 L☉. Stellar evolution modeling indicates an estimated stellar age of 6.03 Gyr and a metallicity of [Fe/H] = 0.282 dex (metal-rich relative to the Sun). From Earth, Kepler-133 shines at apparent V-band magnitude 12.896 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-133 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-133 b sharing its stellar neighborhood alongside Kepler-133 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-133 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,736 K |
| Stellar Radius | 1.4250 R☉ |
| Stellar Mass | 1.0200 M☉ |
| Bolometric Luminosity | 1.972 L☉ |
| Metallicity [Fe/H] | 0.282 dex |
| Stellar Age | 6.030 Gyr |
| Apparent Magnitude | V: 12.896 · G: 12.842 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.083000 AU |
| Orbital Period | 8.13 days |
| Mean Orbital Velocity | 111.1 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 86.2400° |
| Mean Bulk Density | 3.79 g/cm³ (16.3 km/s vesc) |
| Insolation Flux | 408.5800 S⊕ (~556,077 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2131.800 LY (653.600 pc) |