Kepler-1942 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1942 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1942, located approximately 2747.8 light-years (842.49 parsecs) from the Solar System. First announced in 2021 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0593% across the stellar disk), this world measures 2.117 Earth radii and has a measured mass of 5.13 Earth masses. Combining its mass and radius yields a mean bulk density of 2.98 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-1942, Kepler-1942 b completes one full revolution every 4.626 Earth days at a semi-major axis of 0.0516 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 121.3 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 1012 K (+739°C / +1362°F) and receiving 247.34 S⊕ (~336,630 W/m²), Kepler-1942 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1942 is classified as a stellar host with an effective photospheric temperature of 5,834 K, a radius of 0.797 R☉, a mass of 0.852 M☉, an estimated bolometric luminosity of 0.66 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.5 dex (metal-poor relative to the Sun). From Earth, Kepler-1942 shines at apparent V-band magnitude 14.91 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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