11 Com b

Astrophysical Synthesis & Habitability Characterization

11 Com b is a confirmed gas giant exoplanet orbiting the star 11 Com, located approximately 303.9 light-years (93.19 parsecs) from the Solar System. First announced in 2007 by Xinglong Station using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 12.2 Earth radii (1.09 Jupiter radii) and has a measured mass of 4914.898 Earth masses (15.46 Jupiter masses). Combining its mass and radius yields a mean bulk density of 14.92 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 33.02 g⊕ (323.82 m/s²), and an escape velocity of 224.5 km/s.

In its orbital architecture around 11 Com, 11 Com b completes one full revolution every 323.21 Earth days at a semi-major axis of 1.178 AU (comparable to the inner terrestrial zone between Venus, Earth at 1.00 AU, and Mars at 1.52 AU). Its mean orbital velocity is approximately 39.7 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.238 carries the world between 0.8976 AU at periapsis and 1.4584 AU at apoapsis, driving measurable seasonal insolation cycles.

⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 803 K (+530°C / +986°F) and receiving 68.54 S⊕ (~93,281 W/m²), 11 Com b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star 11 Com is classified as a solar-type yellow star of spectral type G8 III with an effective photospheric temperature of 4,874 K, a radius of 13.76 R☉, a mass of 2.09 M☉, an estimated bolometric luminosity of 95.867 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.26 dex (metal-poor relative to the Sun). From Earth, 11 Com shines at apparent V-band magnitude 4.723 (visible to the unaided human eye under dark skies) in the Northern celestial hemisphere.

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