HD 142 c
Astrophysical Synthesis & Habitability Characterization
HD 142 c 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 2012 by Anglo-Australian Telescope using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 12.4 Earth radii (1.11 Jupiter radii) and has a measured mass of 3464.647 Earth masses (10.9 Jupiter masses). Combining its mass and radius yields a mean bulk density of 10.02 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 22.53 g⊕ (220.94 m/s²), and an escape velocity of 187 km/s.
In its orbital architecture around HD 142, HD 142 c completes one full revolution every 10159.643 Earth days (27.82Julian years) at a semi-major axis of 9.811 AU (a wide outer-system orbit beyond Jupiter's 5.20 AU distance in our Solar System). Its mean orbital velocity is approximately 10.5 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.277, swinging from 7.0934 AU at periapsis out to 12.5286 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
❄️ Thermal Regime (Cryogenic Zone): With an equilibrium temperature of 117 K (-156°C / -249°F) and an incident flux of 0.03 S⊕ (~42 W/m²), surface water and volatile species on HD 142 c would remain locked in cryogenic ice phases unless warmed by subsurface tidal or radiogenic heating.
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 c sharing its stellar neighborhood alongside HD 142 A d, HD 142 b.
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) | 9.811000 AU |
| Orbital Period | 10159.643 days |
| Mean Orbital Velocity | 10.5 km/s |
| Orbital Eccentricity (e) | 0.27700 |
| Orbital Inclination (i) | 90.3740° |
| Mean Bulk Density | 10.02 g/cm³ (187 km/s vesc) |
| Insolation Flux | 0.0310 S⊕ (~42 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 85.400 LY (26.185 pc) |