HD 12484 b
Astrophysical Synthesis & Habitability Characterization
HD 12484 b is a confirmed gas giant exoplanet orbiting the star HD 12484, located approximately 157.7 light-years (48.34 parsecs) from the Solar System. First announced in 2016 by Haute-Provence Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 13.2 Earth radii (1.18 Jupiter radii) and has a measured mass of 947.133 Earth masses (2.98 Jupiter masses). Combining its mass and radius yields a mean bulk density of 2.27 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 5.44 g⊕ (53.35 m/s²), and an escape velocity of 94.8 km/s.
In its orbital architecture around HD 12484, HD 12484 b completes one full revolution every 58.83 Earth days at a semi-major axis of 0.297 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 54.9 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.07 carries the world between 0.2762 AU at periapsis and 0.3178 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 524 K (+251°C / +484°F) and receiving 11.93 S⊕ (~16,237 W/m²), HD 12484 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HD 12484 is classified as a warm F-type star of spectral type F8 with an effective photospheric temperature of 5,920 K, a radius of 1.0018 R☉, a mass of 1.01 M☉, an estimated bolometric luminosity of 1.106 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0.05 dex (near-solar heavy-element abundance). From Earth, HD 12484 shines at apparent V-band magnitude 8.18 (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: Haute-Provence Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 12484 |
| Spectral Type | F8 |
| Effective Temp (Teff) | 5,920 K |
| Stellar Radius | 1.0018 R☉ |
| Stellar Mass | 1.0100 M☉ |
| Bolometric Luminosity | 1.106 L☉ |
| Metallicity [Fe/H] | 0.050 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 8.180 · G: 8.045 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.297000 AU |
| Orbital Period | 58.83 days |
| Mean Orbital Velocity | 54.9 km/s |
| Orbital Eccentricity (e) | 0.07000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 2.27 g/cm³ (94.8 km/s vesc) |
| Insolation Flux | 11.9305 S⊕ (~16,237 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 157.700 LY (48.337 pc) |