Kepler-766 b

Astrophysical Synthesis & Habitability Characterization

Kepler-766 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-766, located approximately 7493.8 light-years (2297.62 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.073% across the stellar disk), this world measures 3.39 Earth radii (0.3 Jupiter radii) and has a measured mass of 11.4 Earth masses. Combining its mass and radius yields a mean bulk density of 1.61 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.99 g⊕ (9.71 m/s²), and an escape velocity of 20.5 km/s.

In its orbital architecture around Kepler-766, Kepler-766 b completes one full revolution every 6.1 Earth days at a semi-major axis of 0.066 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 117.7 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 990 K (+717°C / +1323°F) and receiving 227.15 S⊕ (~309,151 W/m²), Kepler-766 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-766 is classified as a stellar host with an effective photospheric temperature of 5,992 K, a radius of 1.15 R☉, a mass of 1.1 M☉, an estimated bolometric luminosity of 1.53 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.63 Gyr and a metallicity of [Fe/H] = 0.09 dex (metal-rich relative to the Sun). From Earth, Kepler-766 shines at apparent V-band magnitude 15.825 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

Discovery Facility: Kepler · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).