HD 6860 b
Astrophysical Synthesis & Habitability Characterization
HD 6860 b is a confirmed gas giant exoplanet orbiting the star HD 6860, located approximately 199.4 light-years (61.13 parsecs) from the Solar System. First announced in 2023 by Bohyunsan Optical Astronomical Observatory 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 8981.831 Earth masses (28.26 Jupiter masses). Combining its mass and radius yields a mean bulk density of 29.39 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 63.43 g⊕ (622.04 m/s²), and an escape velocity of 307.3 km/s.
In its orbital architecture around HD 6860, HD 6860 b completes one full revolution every 663.87 Earth days (1.82Julian years) at a semi-major axis of 2.03 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 33.3 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.28, swinging from 1.4616 AU at periapsis out to 2.5984 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1196 K (+923°C / +1693°F) and receiving 406.44 S⊕ (~553,159 W/m²), HD 6860 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HD 6860 is classified as a low-mass red dwarf of spectral type M0 III with an effective photospheric temperature of 3,802 K, a radius of 86.4 R☉, a mass of 2.49 M☉, an estimated bolometric luminosity of 1399.477 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.03 dex (near-solar heavy-element abundance). From Earth, HD 6860 shines at apparent V-band magnitude 2.068 (visible to the unaided human eye under dark skies) in the Northern 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: Bohyunsan Optical Astronomical Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 6860 |
| Spectral Type | M0 III |
| Effective Temp (Teff) | 3,802 K |
| Stellar Radius | 86.4000 R☉ |
| Stellar Mass | 2.4900 M☉ |
| Bolometric Luminosity | 1399.477 L☉ |
| Metallicity [Fe/H] | -0.030 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 2.068 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 2.030000 AU |
| Orbital Period | 663.87 days |
| Mean Orbital Velocity | 33.3 km/s |
| Orbital Eccentricity (e) | 0.28000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 29.39 g/cm³ (307.3 km/s vesc) |
| Insolation Flux | 406.4355 S⊕ (~553,159 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 199.400 LY (61.125 pc) |