Kepler-119 b
Astrophysical Synthesis & Habitability Characterization
Kepler-119 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-119, located approximately 2289.6 light-years (702 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.1547% across the stellar disk), this world measures 3.6 Earth radii (0.32 Jupiter radii) and has a measured mass of 12.6 Earth masses. Combining its mass and radius yields a mean bulk density of 1.49 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.97 g⊕ (9.51 m/s²), and an escape velocity of 20.9 km/s.
In its orbital architecture around Kepler-119, Kepler-119 b completes one full revolution every 2.422 Earth days at a semi-major axis of 0.035 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 157.2 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 1213 K (+940°C / +1724°F) and receiving 745.29 S⊕ (~1,014,333 W/m²), Kepler-119 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-119 is classified as a stellar host with an effective photospheric temperature of 5,595 K, a radius of 0.839 R☉, a mass of 0.918 M☉, an estimated bolometric luminosity of 0.619 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.63 Gyr and a metallicity of [Fe/H] = 0.01 dex (near-solar heavy-element abundance). From Earth, Kepler-119 shines at apparent V-band magnitude 14.375 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-119 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-119 b sharing its stellar neighborhood alongside Kepler-119 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-119 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,595 K |
| Stellar Radius | 0.8390 R☉ |
| Stellar Mass | 0.9180 M☉ |
| Bolometric Luminosity | 0.619 L☉ |
| Metallicity [Fe/H] | 0.010 dex |
| Stellar Age | 3.630 Gyr |
| Apparent Magnitude | V: 14.375 · G: 14.200 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.035000 AU |
| Orbital Period | 2.422 days |
| Mean Orbital Velocity | 157.2 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.5600° |
| Mean Bulk Density | 1.49 g/cm³ (20.9 km/s vesc) |
| Insolation Flux | 745.2850 S⊕ (~1,014,333 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2289.600 LY (701.996 pc) |