Kepler-1993 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1993 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1993, located approximately 3365.6 light-years (1031.91 parsecs) from the Solar System. First announced in 2023 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0154% across the stellar disk), this world measures 4.15 Earth radii (0.37 Jupiter radii) and has a measured mass of 16.1 Earth masses. Combining its mass and radius yields a mean bulk density of 1.24 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 km/s.

In its orbital architecture around Kepler-1993, Kepler-1993 b completes one full revolution every 26.657 Earth days at a semi-major axis of 0.1943 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 79.3 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 903 K (+630°C / +1166°F) and receiving 157.45 S⊕ (~214,289 W/m²), Kepler-1993 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1993 is classified as a stellar host with an effective photospheric temperature of 5,159 K, a radius of 3.062 R☉, a mass of 1.373 M☉, an estimated bolometric luminosity of 5.959 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.68 Gyr and a metallicity of [Fe/H] = -0.04 dex (near-solar heavy-element abundance). From Earth, Kepler-1993 shines at apparent V-band magnitude 13.451 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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