Kepler-1546 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1546 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1546, located approximately 3039.6 light-years (931.96 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0952% across the stellar disk), this world measures 3.13 Earth radii (0.28 Jupiter radii) and has a measured mass of 9.96 Earth masses. Combining its mass and radius yields a mean bulk density of 1.79 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 20 km/s.

In its orbital architecture around Kepler-1546, Kepler-1546 b completes one full revolution every 19.597 Earth days at a semi-major axis of 0.1366 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 75.8 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 671 K (+398°C / +748°F) and receiving 36.30 S⊕ (~49,407 W/m²), Kepler-1546 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1546 is classified as a stellar host with an effective photospheric temperature of 5,623 K, a radius of 0.93 R☉, a mass of 0.95 M☉, an estimated bolometric luminosity of 0.776 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.72 Gyr and a metallicity of [Fe/H] = 0.01 dex (near-solar heavy-element abundance). From Earth, Kepler-1546 shines at apparent V-band magnitude 15.596 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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