Kepler-1982 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1982 b is a confirmed sub-earth exoplanet orbiting the star Kepler-1982, located approximately 1822.7 light-years (558.86 parsecs) from the Solar System. First announced in 2023 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.004% across the stellar disk), this world measures 0.77 Earth radii and has a measured mass of 0.381 Earth masses. Combining its mass and radius yields a mean bulk density of 4.6 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 0.64 g⊕ (6.28 m/s²), and an escape velocity of 7.9 km/s.

In its orbital architecture around Kepler-1982, Kepler-1982 b completes one full revolution every 3.823 Earth days at a semi-major axis of 0.0511 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 145.4 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 1282 K (+1009°C / +1848°F) and receiving 638.38 S⊕ (~868,835 W/m²), Kepler-1982 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1982 is classified as a stellar host with an effective photospheric temperature of 6,202 K, a radius of 1.122 R☉, a mass of 1.213 M☉, an estimated bolometric luminosity of 1.671 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.63 Gyr and a metallicity of [Fe/H] = 0.21 dex (metal-rich relative to the Sun). From Earth, Kepler-1982 shines at apparent V-band magnitude 12.696 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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