Kepler-1842 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1842 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1842, located approximately 3012.2 light-years (923.55 parsecs) from the Solar System. First announced in 2021 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0364% across the stellar disk), this world measures 2.354 Earth radii and has a measured mass of 6.14 Earth masses. Combining its mass and radius yields a mean bulk density of 2.6 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.11 g⊕ (10.89 m/s²), and an escape velocity of 18.1 km/s.

In its orbital architecture around Kepler-1842, Kepler-1842 b completes one full revolution every 14.026 Earth days at a semi-major axis of 0.116 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 90 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 822 K (+549°C / +1020°F) and receiving 108.07 S⊕ (~147,083 W/m²), Kepler-1842 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1842 is classified as a stellar host with an effective photospheric temperature of 5,970 K, a radius of 1.131 R☉, a mass of 1.057 M☉, an estimated bolometric luminosity of 1.458 L☉. Stellar evolution modeling indicates an estimated stellar age of 7 Gyr and a metallicity of [Fe/H] = 0.06 dex (metal-rich relative to the Sun). From Earth, Kepler-1842 shines at apparent V-band magnitude 14.746 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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