Kepler-1724 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1724 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1724, located approximately 3459.8 light-years (1060.77 parsecs) from the Solar System. First announced in 2021 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0761% across the stellar disk), this world measures 2.837 Earth radii and has a measured mass of 8.43 Earth masses. Combining its mass and radius yields a mean bulk density of 2.04 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.05 g⊕ (10.3 m/s²), and an escape velocity of 19.3 km/s.

In its orbital architecture around Kepler-1724, Kepler-1724 b completes one full revolution every 6.454 Earth days at a semi-major axis of 0.0683 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 115.1 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 999 K (+726°C / +1339°F) and receiving 234.98 S⊕ (~319,808 W/m²), Kepler-1724 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1724 is classified as a stellar host with an effective photospheric temperature of 6,092 K, a radius of 0.943 R☉, a mass of 1.016 M☉, an estimated bolometric luminosity of 1.099 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.3 Gyr and a metallicity of [Fe/H] = -0.22 dex (metal-poor relative to the Sun). From Earth, Kepler-1724 shines at apparent V-band magnitude 14.961 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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