HD 332231 b
Astrophysical Synthesis & Habitability Characterization
HD 332231 b is a confirmed gas giant exoplanet orbiting the star HD 332231, located approximately 263.1 light-years (80.67 parsecs) from the Solar System. First announced in 2020 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.4317% across the stellar disk), this world measures 9.073 Earth radii (0.81 Jupiter radii) and has a measured mass of 74.1 Earth masses (0.23 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.55 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.9 g⊕ (8.83 m/s²), and an escape velocity of 32 km/s.
In its orbital architecture around HD 332231, HD 332231 b completes one full revolution every 18.712 Earth days at a semi-major axis of 0.145 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 84.3 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 798 K (+525°C / +977°F) and receiving 98.09 S⊕ (~133,500 W/m²), HD 332231 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HD 332231 is classified as a warm F-type star of spectral type F8 with an effective photospheric temperature of 6,128 K, a radius of 1.266 R☉, a mass of 1.1642 M☉, an estimated bolometric luminosity of 2.028 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.9 Gyr and a metallicity of [Fe/H] = 0.043 dex (near-solar heavy-element abundance). From Earth, HD 332231 shines at apparent V-band magnitude 8.558 (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: Transiting Exoplanet Survey Satellite (TESS) · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 332231 |
| Spectral Type | F8 |
| Effective Temp (Teff) | 6,128 K |
| Stellar Radius | 1.2660 R☉ |
| Stellar Mass | 1.1642 M☉ |
| Bolometric Luminosity | 2.028 L☉ |
| Metallicity [Fe/H] | 0.043 dex |
| Stellar Age | 2.900 Gyr |
| Apparent Magnitude | V: 8.558 · G: 8.418 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.145000 AU |
| Orbital Period | 18.712 days |
| Mean Orbital Velocity | 84.3 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.6800° |
| Mean Bulk Density | 0.55 g/cm³ (32 km/s vesc) |
| Insolation Flux | 98.0900 S⊕ (~133,500 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 263.100 LY (80.667 pc) |