HD 142 b
Astrophysical Synthesis & Habitability Characterization
HD 142 b is a confirmed gas giant exoplanet orbiting the star HD 142, located approximately 85.4 light-years (26.19 parsecs) from the Solar System. First announced in 2001 by Anglo-Australian Telescope using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 12.7 Earth radii (1.13 Jupiter radii) and has a measured mass of 2256.582 Earth masses (7.1 Jupiter masses). Combining its mass and radius yields a mean bulk density of 6.07 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 13.99 g⊕ (137.2 m/s²), and an escape velocity of 149.1 km/s.
In its orbital architecture around HD 142, HD 142 b completes one full revolution every 351.434 Earth days at a semi-major axis of 1.039 AU (comparable to the inner terrestrial zone between Venus, Earth at 1.00 AU, and Mars at 1.52 AU). Its mean orbital velocity is approximately 32.2 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.158 carries the world between 0.8748 AU at periapsis and 1.2032 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 358 K (+85°C / +185°F) and receiving 2.76 S⊕ (~3,757 W/m²), HD 142 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HD 142 is classified as a warm F-type star of spectral type F7V with an effective photospheric temperature of 6,245 K, a radius of 1.47 R☉, a mass of 1.21 M☉, an estimated bolometric luminosity of 2.949 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.12 Gyr and a metallicity of [Fe/H] = 0.09 dex (metal-rich relative to the Sun). From Earth, HD 142 shines at apparent V-band magnitude 5.7 (visible to the unaided human eye under dark skies) in the Southern celestial hemisphere. The HD 142 system is a multi-planet architecture hosting 3 confirmed worlds, with HD 142 b sharing its stellar neighborhood alongside HD 142 A d, HD 142 c.
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: Anglo-Australian Telescope · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 142 |
| Spectral Type | F7V |
| Effective Temp (Teff) | 6,245 K |
| Stellar Radius | 1.4700 R☉ |
| Stellar Mass | 1.2100 M☉ |
| Bolometric Luminosity | 2.949 L☉ |
| Metallicity [Fe/H] | 0.090 dex |
| Stellar Age | 3.120 Gyr |
| Apparent Magnitude | V: 5.700 · G: 5.584 |
| System Architecture | 2 Stars, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 1.039000 AU |
| Orbital Period | 351.434 days |
| Mean Orbital Velocity | 32.2 km/s |
| Orbital Eccentricity (e) | 0.15800 |
| Orbital Inclination (i) | 59.0000° |
| Mean Bulk Density | 6.07 g/cm³ (149.1 km/s vesc) |
| Insolation Flux | 2.7603 S⊕ (~3,757 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 85.400 LY (26.185 pc) |