Kepler-149 b
Astrophysical Synthesis & Habitability Characterization
Kepler-149 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-149, located approximately 1862.5 light-years (571.03 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.164% across the stellar disk), this world measures 4.21 Earth radii (0.38 Jupiter radii) and has a measured mass of 16.5 Earth masses. Combining its mass and radius yields a mean bulk density of 1.22 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.93 g⊕ (9.12 m/s²), and an escape velocity of 22.1 km/s.
In its orbital architecture around Kepler-149, Kepler-149 b completes one full revolution every 29.199 Earth days at a semi-major axis of 0.184 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 68.6 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 540 K (+267°C / +513°F) and receiving 23.64 S⊕ (~32,174 W/m²), Kepler-149 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-149 is classified as a stellar host with an effective photospheric temperature of 5,381 K, a radius of 0.953 R☉, a mass of 1.013 M☉, an estimated bolometric luminosity of 0.683 L☉. Stellar evolution modeling indicates an estimated stellar age of 14 Gyr and a metallicity of [Fe/H] = 0.381 dex (metal-rich relative to the Sun). From Earth, Kepler-149 shines at apparent V-band magnitude 14.152 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-149 system is a multi-planet architecture hosting 3 confirmed worlds, with Kepler-149 b sharing its stellar neighborhood alongside Kepler-149 c, Kepler-149 d.
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-149 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,381 K |
| Stellar Radius | 0.9530 R☉ |
| Stellar Mass | 1.0130 M☉ |
| Bolometric Luminosity | 0.683 L☉ |
| Metallicity [Fe/H] | 0.381 dex |
| Stellar Age | 14.000 Gyr |
| Apparent Magnitude | V: 14.152 · G: 14.019 |
| System Architecture | 1 Star, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.184000 AU |
| Orbital Period | 29.199 days |
| Mean Orbital Velocity | 68.6 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.9500° |
| Mean Bulk Density | 1.22 g/cm³ (22.1 km/s vesc) |
| Insolation Flux | 23.6400 S⊕ (~32,174 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1862.500 LY (571.034 pc) |