Kepler-463 b

Astrophysical Synthesis & Habitability Characterization

Kepler-463 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-463, located approximately 1287.7 light-years (394.8 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0965% across the stellar disk), this world measures 3.05 Earth radii (0.27 Jupiter radii) and has a measured mass of 9.53 Earth masses. Combining its mass and radius yields a mean bulk density of 1.85 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.02 g⊕ (10 m/s²), and an escape velocity of 19.8 km/s.

In its orbital architecture around Kepler-463, Kepler-463 b completes one full revolution every 8.981 Earth days at a semi-major axis of 0.07925 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 96 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 880 K (+607°C / +1125°F) and receiving 166.04 S⊕ (~225,979 W/m²), Kepler-463 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-463 is classified as a stellar host with an effective photospheric temperature of 5,661 K, a radius of 0.9 R☉, a mass of 0.87 M☉, an estimated bolometric luminosity of 0.746 L☉. Stellar evolution modeling indicates an estimated stellar age of 7.41 Gyr and a metallicity of [Fe/H] = -0.28 dex (metal-poor relative to the Sun). From Earth, Kepler-463 shines at apparent V-band magnitude 12.999 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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