HD 457 b
Astrophysical Synthesis & Habitability Characterization
HD 457 b is a confirmed gas giant exoplanet orbiting the star HD 457, located approximately 179.5 light-years (55.04 parsecs) from the Solar System. First announced in 2022 by Multiple Observatories using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 11.9 Earth radii (1.06 Jupiter radii) and has a measured mass of 8445.336 Earth masses (26.57 Jupiter masses). Combining its mass and radius yields a mean bulk density of 27.63 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 59.64 g⊕ (584.87 m/s²), and an escape velocity of 298 km/s.
In its orbital architecture around HD 457, HD 457 b completes one full revolution every 20324.582 Earth days (55.65Julian years) at a semi-major axis of 15.369 AU (a wide outer-system orbit beyond Jupiter's 5.20 AU distance in our Solar System). Its mean orbital velocity is approximately 8.2 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.565, swinging from 6.6855 AU at periapsis out to 24.0525 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
❄️ Thermal Regime (Cryogenic Zone): With an equilibrium temperature of 85 K (-188°C / -306°F) and an incident flux of 0.01 S⊕ (~12 W/m²), surface water and volatile species on HD 457 b would remain locked in cryogenic ice phases unless warmed by subsurface tidal or radiogenic heating.
The host star HD 457 is classified as a stellar host with an effective photospheric temperature of 6,114 K, a radius of 1.2819 R☉, a mass of 1.15 M☉, an estimated bolometric luminosity of 2.06 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0.34 dex (metal-rich relative to the Sun). From Earth, HD 457 shines at apparent V-band magnitude 7.72 (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: Multiple Observatories · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 457 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,114 K |
| Stellar Radius | 1.2819 R☉ |
| Stellar Mass | 1.1500 M☉ |
| Bolometric Luminosity | 2.06 L☉ |
| Metallicity [Fe/H] | 0.340 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 7.720 · G: 7.578 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 15.369000 AU |
| Orbital Period | 20324.582 days |
| Mean Orbital Velocity | 8.2 km/s |
| Orbital Eccentricity (e) | 0.56500 |
| Orbital Inclination (i) | 62.5850° |
| Mean Bulk Density | 27.63 g/cm³ (298 km/s vesc) |
| Insolation Flux | 0.0088 S⊕ (~12 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 179.500 LY (55.038 pc) |