Kepler-1223 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1223 b is a confirmed terrestrial exoplanet orbiting the star Kepler-1223, located approximately 1500.2 light-years (459.96 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0222% across the stellar disk), this world measures 1.22 Earth radii and has a measured mass of 1.98 Earth masses. Combining its mass and radius yields a mean bulk density of 6.01 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.33 g⊕ (13.04 m/s²), and an escape velocity of 14.3 km/s.

In its orbital architecture around Kepler-1223, Kepler-1223 b completes one full revolution every 16.301 Earth days at a semi-major axis of 0.1186 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 79.2 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 557 K (+284°C / +543°F) and receiving 20.51 S⊕ (~27,914 W/m²), Kepler-1223 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1223 is classified as a stellar host with an effective photospheric temperature of 4,870 K, a radius of 0.75 R☉, a mass of 0.8 M☉, an estimated bolometric luminosity of 0.284 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.63 Gyr and a metallicity of [Fe/H] = 0.04 dex (near-solar heavy-element abundance). From Earth, Kepler-1223 shines at apparent V-band magnitude 14.911 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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