Kepler-966 b

Astrophysical Synthesis & Habitability Characterization

Kepler-966 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-966, located approximately 3352.2 light-years (1027.8 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.1378% across the stellar disk), this world measures 4.13 Earth radii (0.37 Jupiter radii) and has a measured mass of 16 Earth masses. Combining its mass and radius yields a mean bulk density of 1.25 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.94 g⊕ (9.22 m/s²), and an escape velocity of 22 km/s.

In its orbital architecture around Kepler-966, Kepler-966 b completes one full revolution every 99.748 Earth days at a semi-major axis of 0.3907 AU (situated at an orbital separation between Mercury's 0.39 AU and Venus's 0.72 AU). Its mean orbital velocity is approximately 42.6 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 391 K (+118°C / +244°F) and receiving 10.97 S⊕ (~14,933 W/m²), Kepler-966 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-966 is classified as a stellar host with an effective photospheric temperature of 5,840 K, a radius of 1.02 R☉, a mass of 1.02 M☉, an estimated bolometric luminosity of 1.086 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.07 Gyr and a metallicity of [Fe/H] = 0.04 dex (near-solar heavy-element abundance). From Earth, Kepler-966 shines at apparent V-band magnitude 14.731 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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