HD 73267 b
Astrophysical Synthesis & Habitability Characterization
HD 73267 b is a confirmed gas giant exoplanet orbiting the star HD 73267, located approximately 164.4 light-years (50.41 parsecs) from the Solar System. First announced in 2008 by La Silla Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 13 Earth radii (1.16 Jupiter radii) and has a measured mass of 1321.531 Earth masses (4.16 Jupiter masses). Combining its mass and radius yields a mean bulk density of 3.32 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 7.82 g⊕ (76.69 m/s²), and an escape velocity of 112.8 km/s.
In its orbital architecture around HD 73267, HD 73267 b completes one full revolution every 1257.992 Earth days (3.44Julian years) at a semi-major axis of 2.229 AU (corresponding to the middle-system regime between Mars at 1.52 AU and Jupiter at 5.20 AU). Its mean orbital velocity is approximately 19.3 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.261, swinging from 1.6472 AU at periapsis out to 2.8108 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
❄️ Thermal Regime (Cryogenic Zone): With an equilibrium temperature of 166 K (-107°C / -161°F) and an incident flux of 0.16 S⊕ (~215 W/m²), surface water and volatile species on HD 73267 b would remain locked in cryogenic ice phases unless warmed by subsurface tidal or radiogenic heating.
The host star HD 73267 is classified as an orange K-type star of spectral type K0 V with an effective photospheric temperature of 5,387 K, a radius of 0.909 R☉, a mass of 0.93 M☉, an estimated bolometric luminosity of 0.624 L☉. Stellar evolution modeling indicates an estimated stellar age of 8.14 Gyr and a metallicity of [Fe/H] = 0.03 dex (near-solar heavy-element abundance). From Earth, HD 73267 shines at apparent V-band magnitude 8.9 (accessible to binoculars and small amateur telescopes) in the Southern celestial hemisphere. The HD 73267 system is a multi-planet architecture hosting 2 confirmed worlds, with HD 73267 b sharing its stellar neighborhood alongside HD 73267 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: La Silla Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 73267 |
| Spectral Type | K0 V |
| Effective Temp (Teff) | 5,387 K |
| Stellar Radius | 0.9090 R☉ |
| Stellar Mass | 0.9300 M☉ |
| Bolometric Luminosity | 0.624 L☉ |
| Metallicity [Fe/H] | 0.030 dex |
| Stellar Age | 8.140 Gyr |
| Apparent Magnitude | V: 8.900 · G: 8.678 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 2.229000 AU |
| Orbital Period | 1257.992 days |
| Mean Orbital Velocity | 19.3 km/s |
| Orbital Eccentricity (e) | 0.26100 |
| Orbital Inclination (i) | 130.8430° |
| Mean Bulk Density | 3.32 g/cm³ (112.8 km/s vesc) |
| Insolation Flux | 0.1577 S⊕ (~215 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 164.400 LY (50.409 pc) |