HIP 78530 b
Astrophysical Synthesis & Habitability Characterization
HIP 78530 b is a confirmed gas giant exoplanet orbiting the star HIP 78530, located approximately 446 light-years (136.76 parsecs) from the Solar System. First announced in 2010 by Gemini Observatory using the Imaging detection technique (resolved directly via high-contrast coronagraphic or interferometric imaging), this world measures 12 Earth radii (1.07 Jupiter radii) and has a measured mass of 7300 Earth masses (22.97 Jupiter masses). Combining its mass and radius yields a mean bulk density of 23.29 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 50.69 g⊕ (497.1 m/s²), and an escape velocity of 275.9 km/s.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 2700 K (+2427°C / +4401°F), HIP 78530 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HIP 78530 is classified as a massive B-type star of spectral type B9 V with an effective photospheric temperature of 10,500 K, a radius of 2.1088 R☉, a mass of 2.5 M☉, an estimated bolometric luminosity of 48.497 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.005 Gyr and a metallicity of [Fe/H] = -0.5 dex (metal-poor relative to the Sun). From Earth, HIP 78530 shines at apparent V-band magnitude 7.169 (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: Gemini Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HIP 78530 |
| Spectral Type | B9 V |
| Effective Temp (Teff) | 10,500 K |
| Stellar Radius | 2.1088 R☉ |
| Stellar Mass | 2.5000 M☉ |
| Bolometric Luminosity | 48.497 L☉ |
| Metallicity [Fe/H] | -0.500 dex |
| Stellar Age | 0.005 Gyr |
| Apparent Magnitude | V: 7.169 · G: 7.147 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 740.000000 AU |
| Orbital Period | — |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 23.29 g/cm³ (275.9 km/s vesc) |
| Insolation Flux | 0.0000 S⊕ |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 446.000 LY (136.759 pc) |