HD 206610 b
Astrophysical Synthesis & Habitability Characterization
HD 206610 b is a confirmed gas giant exoplanet orbiting the star HD 206610, located approximately 480.1 light-years (147.19 parsecs) from the Solar System. First announced in 2009 by W. M. Keck Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 13.4 Earth radii (1.2 Jupiter radii) and has a measured mass of 647.102 Earth masses (2.04 Jupiter masses). Combining its mass and radius yields a mean bulk density of 1.48 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 3.6 g⊕ (35.3 m/s²), and an escape velocity of 77.7 km/s.
In its orbital architecture around HD 206610, HD 206610 b completes one full revolution every 673.2 Earth days (1.84Julian years) at a semi-major axis of 1.74 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 28.1 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.1 carries the world between 1.566 AU at periapsis and 1.914 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 438 K (+165°C / +329°F) and receiving 6.24 S⊕ (~8,496 W/m²), HD 206610 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HD 206610 is classified as an orange K-type star of spectral type K0 III with an effective photospheric temperature of 4,842 K, a radius of 6.12 R☉, a mass of 1.55 M☉, an estimated bolometric luminosity of 18.471 L☉. Stellar evolution modeling indicates an estimated stellar age of 3 Gyr and a metallicity of [Fe/H] = 0.14 dex (metal-rich relative to the Sun). From Earth, HD 206610 shines at apparent V-band magnitude 8.34 (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: W. M. Keck Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 206610 |
| Spectral Type | K0 III |
| Effective Temp (Teff) | 4,842 K |
| Stellar Radius | 6.1200 R☉ |
| Stellar Mass | 1.5500 M☉ |
| Bolometric Luminosity | 18.471 L☉ |
| Metallicity [Fe/H] | 0.140 dex |
| Stellar Age | 3.000 Gyr |
| Apparent Magnitude | V: 8.340 · G: 8.065 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 1.740000 AU |
| Orbital Period | 673.2 days |
| Mean Orbital Velocity | 28.1 km/s |
| Orbital Eccentricity (e) | 0.10000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 1.48 g/cm³ (77.7 km/s vesc) |
| Insolation Flux | 6.2426 S⊕ (~8,496 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 480.100 LY (147.192 pc) |