Kepler-188 b
Astrophysical Synthesis & Habitability Characterization
Kepler-188 b is a confirmed super-earth exoplanet orbiting the star Kepler-188, located approximately 3159 light-years (968.54 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0182% across the stellar disk), this world measures 1.68 Earth radii and has a measured mass of 3.46 Earth masses. Combining its mass and radius yields a mean bulk density of 4.02 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.23 g⊕ (12.06 m/s²), and an escape velocity of 16.1 km/s.
In its orbital architecture around Kepler-188, Kepler-188 b completes one full revolution every 2.062 Earth days at a semi-major axis of 0.032 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 168.8 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 1463 K (+1190°C / +2174°F) and receiving 1,069.24 S⊕ (~1,455,229 W/m²), Kepler-188 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-188 is classified as a stellar host with an effective photospheric temperature of 6,021 K, a radius of 1.141 R☉, a mass of 1.021 M☉, an estimated bolometric luminosity of 1.535 L☉. Stellar evolution modeling indicates an estimated stellar age of 5.8 Gyr and a metallicity of [Fe/H] = 0.15 dex (metal-rich relative to the Sun). From Earth, Kepler-188 shines at apparent V-band magnitude 14.719 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-188 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-188 b sharing its stellar neighborhood alongside Kepler-188 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-188 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,021 K |
| Stellar Radius | 1.1410 R☉ |
| Stellar Mass | 1.0210 M☉ |
| Bolometric Luminosity | 1.535 L☉ |
| Metallicity [Fe/H] | 0.150 dex |
| Stellar Age | 5.800 Gyr |
| Apparent Magnitude | V: 14.719 · G: 14.634 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.032000 AU |
| Orbital Period | 2.062 days |
| Mean Orbital Velocity | 168.8 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 85.5400° |
| Mean Bulk Density | 4.02 g/cm³ (16.1 km/s vesc) |
| Insolation Flux | 1069.2350 S⊕ (~1,455,229 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 3159.000 LY (968.544 pc) |