HD 19615 b
Astrophysical Synthesis & Habitability Characterization
HD 19615 b is a confirmed gas giant exoplanet orbiting the star HD 19615, located approximately 864.8 light-years (265.16 parsecs) from the Solar System. First announced in 2022 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 12.6 Earth radii (1.12 Jupiter radii) and has a measured mass of 2701.541 Earth masses (8.5 Jupiter masses). Combining its mass and radius yields a mean bulk density of 7.45 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 17.02 g⊕ (166.91 m/s²), and an escape velocity of 163.8 km/s.
In its orbital architecture around HD 19615, HD 19615 b completes one full revolution every 402 Earth days (1.1Julian years) at a semi-major axis of 1.1 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 29.8 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.2 carries the world between 0.88 AU at periapsis and 1.32 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1114 K (+841°C / +1546°F) and receiving 270.25 S⊕ (~367,807 W/m²), HD 19615 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HD 19615 is classified as an orange K-type star of spectral type K0 with an effective photospheric temperature of 4,263 K, a radius of 32.3 R☉, a mass of 1.1 M☉, an estimated bolometric luminosity of 309.141 L☉. Stellar evolution modeling indicates an estimated stellar age of 6.7 Gyr and a metallicity of [Fe/H] = -0.31 dex (metal-poor relative to the Sun). From Earth, HD 19615 shines at apparent V-band magnitude 6.556 (accessible to binoculars and small amateur telescopes) 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 19615 |
| Spectral Type | K0 |
| Effective Temp (Teff) | 4,263 K |
| Stellar Radius | 32.3000 R☉ |
| Stellar Mass | 1.1000 M☉ |
| Bolometric Luminosity | 309.141 L☉ |
| Metallicity [Fe/H] | -0.310 dex |
| Stellar Age | 6.700 Gyr |
| Apparent Magnitude | V: 6.556 · G: 6.020 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 1.100000 AU |
| Orbital Period | 402 days |
| Mean Orbital Velocity | 29.8 km/s |
| Orbital Eccentricity (e) | 0.20000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 7.45 g/cm³ (163.8 km/s vesc) |
| Insolation Flux | 270.2479 S⊕ (~367,807 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 864.800 LY (265.155 pc) |