Kepler-1219 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1219 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1219, located approximately 2873.1 light-years (880.9 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.01% across the stellar disk), this world measures 2.12 Earth radii and has a measured mass of 5.14 Earth masses. Combining its mass and radius yields a mean bulk density of 2.97 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.14 g⊕ (11.18 m/s²), and an escape velocity of 17.4 km/s.

In its orbital architecture around Kepler-1219, Kepler-1219 b completes one full revolution every 16.105 Earth days at a semi-major axis of 0.14146 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 95.6 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 1159 K (+886°C / +1627°F) and receiving 430.69 S⊕ (~586,170 W/m²), Kepler-1219 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1219 is classified as a stellar host with an effective photospheric temperature of 5,944 K, a radius of 1.94 R☉, a mass of 1.25 M☉, an estimated bolometric luminosity of 4.215 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.37 Gyr and a metallicity of [Fe/H] = 0.05 dex (near-solar heavy-element abundance). From Earth, Kepler-1219 shines at apparent V-band magnitude 12.339 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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