Kepler-1880 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1880 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1880, located approximately 1992.9 light-years (611.04 parsecs) from the Solar System. First announced in 2021 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.1341% 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-1880, Kepler-1880 b completes one full revolution every 6.309 Earth days at a semi-major axis of 0.054 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 93.1 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 606 K (+333°C / +631°F) and receiving 31.73 S⊕ (~43,185 W/m²), Kepler-1880 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1880 is classified as a stellar host with an effective photospheric temperature of 4,380 K, a radius of 0.53 R☉, a mass of 0.524 M☉, an estimated bolometric luminosity of 0.093 L☉. Stellar evolution modeling indicates an estimated stellar age of 13.6 Gyr and a metallicity of [Fe/H] = -0.92 dex (metal-poor relative to the Sun). From Earth, Kepler-1880 shines at apparent V-band magnitude 16.088 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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