Kepler-1916 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1916 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1916, located approximately 6705.2 light-years (2055.82 parsecs) from the Solar System. First announced in 2021 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0483% across the stellar disk), this world measures 2.618 Earth radii and has a measured mass of 7.35 Earth masses. Combining its mass and radius yields a mean bulk density of 2.26 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.07 g⊕ (10.49 m/s²), and an escape velocity of 18.7 km/s.

In its orbital architecture around Kepler-1916, Kepler-1916 b completes one full revolution every 31.254 Earth days at a semi-major axis of 0.2053 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 71.5 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 635 K (+362°C / +684°F) and receiving 38.54 S⊕ (~52,453 W/m²), Kepler-1916 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1916 is classified as a stellar host with an effective photospheric temperature of 6,246 K, a radius of 1.092 R☉, a mass of 1.18 M☉, an estimated bolometric luminosity of 1.628 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0.07 dex (metal-rich relative to the Sun). From Earth, Kepler-1916 shines at apparent V-band magnitude 15.779 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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