Kepler-1734 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1734 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1734, located approximately 4836.3 light-years (1482.83 parsecs) from the Solar System. First announced in 2021 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0852% across the stellar disk), this world measures 3.089 Earth radii (0.28 Jupiter radii) and has a measured mass of 9.74 Earth masses. Combining its mass and radius yields a mean bulk density of 1.82 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.02 g⊕ (10 m/s²), and an escape velocity of 19.9 km/s.

In its orbital architecture around Kepler-1734, Kepler-1734 b completes one full revolution every 6.797 Earth days at a semi-major axis of 0.0714 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 114.3 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 985 K (+712°C / +1314°F) and receiving 222.91 S⊕ (~303,381 W/m²), Kepler-1734 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1734 is classified as a stellar host with an effective photospheric temperature of 6,061 K, a radius of 0.97 R☉, a mass of 1.05 M☉, an estimated bolometric luminosity of 1.139 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.3 Gyr and a metallicity of [Fe/H] = -0.1 dex (near-solar heavy-element abundance). From Earth, Kepler-1734 shines at apparent V-band magnitude 15.598 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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