Kepler-816 b

Astrophysical Synthesis & Habitability Characterization

Kepler-816 b is a confirmed gas giant exoplanet orbiting the star Kepler-816, located approximately 3208.4 light-years (983.7 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 1.2198% across the stellar disk), this world measures 10.24 Earth radii (0.91 Jupiter radii) and has a measured mass of 74.5 Earth masses (0.23 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.38 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.71 g⊕ (6.96 m/s²), and an escape velocity of 30.2 km/s.

In its orbital architecture around Kepler-816, Kepler-816 b completes one full revolution every 10.507 Earth days at a semi-major axis of 0.0895 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 92.7 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 668 K (+395°C / +743°F) and receiving 50.56 S⊕ (~68,816 W/m²), Kepler-816 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-816 is classified as a stellar host with an effective photospheric temperature of 5,286 K, a radius of 0.85 R☉, a mass of 0.9 M☉, an estimated bolometric luminosity of 0.506 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.17 Gyr and a metallicity of [Fe/H] = 0.16 dex (metal-rich relative to the Sun). From Earth, Kepler-816 shines at apparent V-band magnitude 16.365 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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