HD 111232 b
Astrophysical Synthesis & Habitability Characterization
HD 111232 b is a confirmed gas giant exoplanet orbiting the star HD 111232, located approximately 94.4 light-years (28.96 parsecs) from the Solar System. First announced in 2003 by La Silla Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 12.6 Earth radii (1.12 Jupiter radii) and has a measured mass of 2531.503 Earth masses (7.96 Jupiter masses). Combining its mass and radius yields a mean bulk density of 6.98 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 15.95 g⊕ (156.42 m/s²), and an escape velocity of 158.6 km/s.
In its orbital architecture around HD 111232, HD 111232 b completes one full revolution every 1169.132 Earth days (3.2Julian years) at a semi-major axis of 2.148 AU (corresponding to the middle-system regime between Mars at 1.52 AU and Jupiter at 5.20 AU). Its mean orbital velocity is approximately 20 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.214 carries the world between 1.6883 AU at periapsis and 2.6077 AU at apoapsis, driving measurable seasonal insolation cycles.
❄️ Thermal Regime (Cryogenic Zone): With an equilibrium temperature of 172 K (-101°C / -150°F) and an incident flux of 0.15 S⊕ (~204 W/m²), surface water and volatile species on HD 111232 b would remain locked in cryogenic ice phases unless warmed by subsurface tidal or radiogenic heating.
The host star HD 111232 is classified as a solar-type yellow star of spectral type G8 V with an effective photospheric temperature of 5,512 K, a radius of 0.9 R☉, a mass of 0.96 M☉, an estimated bolometric luminosity of 0.671 L☉. Stellar evolution modeling indicates an estimated stellar age of 5.2 Gyr and a metallicity of [Fe/H] = -0.36 dex (metal-poor relative to the Sun). From Earth, HD 111232 shines at apparent V-band magnitude 7.59 (accessible to binoculars and small amateur telescopes) in the Southern celestial hemisphere. The HD 111232 system is a multi-planet architecture hosting 2 confirmed worlds, with HD 111232 b sharing its stellar neighborhood alongside HD 111232 c.
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: La Silla Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 111232 |
| Spectral Type | G8 V |
| Effective Temp (Teff) | 5,512 K |
| Stellar Radius | 0.9000 R☉ |
| Stellar Mass | 0.9600 M☉ |
| Bolometric Luminosity | 0.671 L☉ |
| Metallicity [Fe/H] | -0.360 dex |
| Stellar Age | 5.200 Gyr |
| Apparent Magnitude | V: 7.590 · G: 7.405 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 2.148000 AU |
| Orbital Period | 1169.132 days |
| Mean Orbital Velocity | 20 km/s |
| Orbital Eccentricity (e) | 0.21400 |
| Orbital Inclination (i) | 93.5210° |
| Mean Bulk Density | 6.98 g/cm³ (158.6 km/s vesc) |
| Insolation Flux | 0.1496 S⊕ (~204 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 94.400 LY (28.957 pc) |