Kepler-1326 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1326 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1326, located approximately 2277.6 light-years (698.33 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0485% across the stellar disk), this world measures 4.18 Earth radii (0.37 Jupiter radii) and has a measured mass of 16.3 Earth masses. Combining its mass and radius yields a mean bulk density of 1.23 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.93 g⊕ (9.12 m/s²), and an escape velocity of 22.1 km/s.

In its orbital architecture around Kepler-1326, Kepler-1326 b completes one full revolution every 42.351 Earth days at a semi-major axis of 0.2743 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 70.5 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 938 K (+665°C / +1229°F) and receiving 47.84 S⊕ (~65,110 W/m²), Kepler-1326 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1326 is classified as a stellar host with an effective photospheric temperature of 6,725 K, a radius of 1.74 R☉, a mass of 1.45 M☉, an estimated bolometric luminosity of 5.556 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.7 Gyr and a metallicity of [Fe/H] = 0.02 dex (near-solar heavy-element abundance). From Earth, Kepler-1326 shines at apparent V-band magnitude 12.842 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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