HD 22532 b
Astrophysical Synthesis & Habitability Characterization
HD 22532 b is a confirmed gas giant exoplanet orbiting the star HD 22532, located approximately 525.7 light-years (161.18 parsecs) from the Solar System. First announced in 2022 by La Silla Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 13.4 Earth radii (1.2 Jupiter radii) and has a measured mass of 673.796 Earth masses (2.12 Jupiter masses). Combining its mass and radius yields a mean bulk density of 1.54 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 3.75 g⊕ (36.77 m/s²), and an escape velocity of 79.3 km/s.
In its orbital architecture around HD 22532, HD 22532 b completes one full revolution every 872.6 Earth days (2.39Julian years) at a semi-major axis of 1.9 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 23.7 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.03 (ranging from 1.843 AU at periapsis to 1.957 AU at apoapsis), the planet experiences minimal orbital distance variation.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 420 K (+147°C / +297°F) and receiving 5.21 S⊕ (~7,088 W/m²), HD 22532 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HD 22532 is classified as a solar-type yellow star of spectral type G8 III/IV with an effective photospheric temperature of 5,038 K, a radius of 5.69 R☉, a mass of 1.57 M☉, an estimated bolometric luminosity of 18.713 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.19 dex (metal-poor relative to the Sun). From Earth, HD 22532 shines at apparent V-band magnitude 7.85 (accessible to binoculars and small amateur telescopes) in the Southern 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: La Silla Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 22532 |
| Spectral Type | G8 III/IV |
| Effective Temp (Teff) | 5,038 K |
| Stellar Radius | 5.6900 R☉ |
| Stellar Mass | 1.5700 M☉ |
| Bolometric Luminosity | 18.713 L☉ |
| Metallicity [Fe/H] | -0.190 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 7.850 · G: 7.604 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 1.900000 AU |
| Orbital Period | 872.6 days |
| Mean Orbital Velocity | 23.7 km/s |
| Orbital Eccentricity (e) | 0.03000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 1.54 g/cm³ (79.3 km/s vesc) |
| Insolation Flux | 5.2078 S⊕ (~7,088 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 525.700 LY (161.183 pc) |