HD 180314 b
Astrophysical Synthesis & Habitability Characterization
HD 180314 b is a confirmed gas giant exoplanet orbiting the star HD 180314, located approximately 399.1 light-years (122.36 parsecs) from the Solar System. First announced in 2010 by Subaru Telescope using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 12 Earth radii (1.07 Jupiter radii) and has a measured mass of 7216.93 Earth masses (22.71 Jupiter masses). Combining its mass and radius yields a mean bulk density of 23.03 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 50.12 g⊕ (491.51 m/s²), and an escape velocity of 274.3 km/s.
In its orbital architecture around HD 180314, HD 180314 b completes one full revolution every 394.73 Earth days (1.08Julian years) at a semi-major axis of 1.448 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 39.9 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.247 carries the world between 1.0903 AU at periapsis and 1.8057 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 598 K (+325°C / +617°F) and receiving 20.99 S⊕ (~28,561 W/m²), HD 180314 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HD 180314 is classified as an orange K-type star of spectral type K0 with an effective photospheric temperature of 4,917 K, a radius of 9.2 R☉, a mass of 2.6 M☉, an estimated bolometric luminosity of 44.388 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.295 Gyr and a metallicity of [Fe/H] = 0.2 dex (metal-rich relative to the Sun). From Earth, HD 180314 shines at apparent V-band magnitude 6.615 (accessible to binoculars and small amateur telescopes) in the Northern celestial hemisphere.
Methodology: Computed using the Schulze-Makuch et al. (2011) weighted metric comparing physical interior (radius, estimated density) and surface thermal regime (escape velocity, equilibrium temperature).
Discovery Facility: Subaru Telescope · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 180314 |
| Spectral Type | K0 |
| Effective Temp (Teff) | 4,917 K |
| Stellar Radius | 9.2000 R☉ |
| Stellar Mass | 2.6000 M☉ |
| Bolometric Luminosity | 44.388 L☉ |
| Metallicity [Fe/H] | 0.200 dex |
| Stellar Age | 1.295 Gyr |
| Apparent Magnitude | V: 6.615 · G: 6.346 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 1.448000 AU |
| Orbital Period | 394.73 days |
| Mean Orbital Velocity | 39.9 km/s |
| Orbital Eccentricity (e) | 0.24700 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 23.03 g/cm³ (274.3 km/s vesc) |
| Insolation Flux | 20.9853 S⊕ (~28,561 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 399.100 LY (122.362 pc) |