HD 179079 b

Astrophysical Synthesis & Habitability Characterization

HD 179079 b is a confirmed gas giant exoplanet orbiting the star HD 179079, located approximately 227.4 light-years (69.71 parsecs) from the Solar System. First announced in 2008 by W. M. Keck Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world has a minimum or true mass of 4195.335 Earth masses (13.2 M♃), while its physical transit radius has not yet been geometrically observed.

In its orbital architecture around HD 179079, HD 179079 b completes one full revolution every 14.479 Earth days at a semi-major axis of 0.1214 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 91.2 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.049 (ranging from 0.1155 AU at periapsis to 0.1273 AU at apoapsis), the planet experiences minimal orbital distance variation.

⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 998 K (+725°C / +1337°F) and receiving 162.77 S⊕ (~221,524 W/m²), HD 179079 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star HD 179079 is classified as a solar-type yellow star of spectral type G5 IV with an effective photospheric temperature of 5,646 K, a radius of 1.63 R☉, a mass of 1.14 M☉, an estimated bolometric luminosity of 2.422 L☉. Stellar evolution modeling indicates an estimated stellar age of 6.99 Gyr and a metallicity of [Fe/H] = 0.24 dex (metal-rich relative to the Sun). From Earth, HD 179079 shines at apparent V-band magnitude 7.95 (accessible to binoculars and small amateur telescopes) in the Southern celestial hemisphere.

Discovery Facility: W. M. Keck Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).