Kepler-1442 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1442 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1442, located approximately 1985.2 light-years (608.68 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0626% across the stellar disk), this world measures 3.93 Earth radii (0.35 Jupiter radii) and has a measured mass of 14.7 Earth masses. Combining its mass and radius yields a mean bulk density of 1.34 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.95 g⊕ (9.32 m/s²), and an escape velocity of 21.6 km/s.

In its orbital architecture around Kepler-1442, Kepler-1442 b completes one full revolution every 81.416 Earth days at a semi-major axis of 0.40814 AU (situated at an orbital separation between Mercury's 0.39 AU and Venus's 0.72 AU). Its mean orbital velocity is approximately 54.5 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 522 K (+249°C / +480°F) and receiving 25.97 S⊕ (~35,348 W/m²), Kepler-1442 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1442 is classified as a stellar host with an effective photospheric temperature of 6,394 K, a radius of 1.44 R☉, a mass of 1.34 M☉, an estimated bolometric luminosity of 3.11 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.7 Gyr and a metallicity of [Fe/H] = 0.26 dex (metal-rich relative to the Sun). From Earth, Kepler-1442 shines at apparent V-band magnitude 12.114 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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