Kepler-769 b
Astrophysical Synthesis & Habitability Characterization
Kepler-769 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-769, located approximately 3814.6 light-years (1169.57 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0437% across the stellar disk), this world measures 2.92 Earth radii and has a measured mass of 8.85 Earth masses. Combining its mass and radius yields a mean bulk density of 1.96 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.04 g⊕ (10.2 m/s²), and an escape velocity of 19.5 km/s.
In its orbital architecture around Kepler-769, Kepler-769 b completes one full revolution every 7.426 Earth days at a semi-major axis of 0.0778 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 114 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 1037 K (+764°C / +1407°F) and receiving 241.13 S⊕ (~328,175 W/m²), Kepler-769 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-769 is classified as a stellar host with an effective photospheric temperature of 6,186 K, a radius of 1.28 R☉, a mass of 1.19 M☉, an estimated bolometric luminosity of 2.153 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.88 Gyr and a metallicity of [Fe/H] = 0.06 dex (metal-rich relative to the Sun). From Earth, Kepler-769 shines at apparent V-band magnitude 14.984 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-769 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-769 b sharing its stellar neighborhood alongside Kepler-769 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-769 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,186 K |
| Stellar Radius | 1.2800 R☉ |
| Stellar Mass | 1.1900 M☉ |
| Bolometric Luminosity | 2.153 L☉ |
| Metallicity [Fe/H] | 0.060 dex |
| Stellar Age | 2.880 Gyr |
| Apparent Magnitude | V: 14.984 · G: 14.760 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.077800 AU |
| Orbital Period | 7.426 days |
| Mean Orbital Velocity | 114 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.6500° |
| Mean Bulk Density | 1.96 g/cm³ (19.5 km/s vesc) |
| Insolation Flux | 241.1280 S⊕ (~328,175 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 3814.600 LY (1169.570 pc) |