eps CrB b
Astrophysical Synthesis & Habitability Characterization
eps CrB b is a confirmed gas giant exoplanet orbiting the star eps CrB, located approximately 227.9 light-years (69.87 parsecs) from the Solar System. First announced in 2012 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 12.7 Earth radii (1.13 Jupiter radii) and has a measured mass of 2129.461 Earth masses (6.7 Jupiter masses). Combining its mass and radius yields a mean bulk density of 5.73 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 13.2 g⊕ (129.45 m/s²), and an escape velocity of 144.8 km/s.
In its orbital architecture around eps CrB, eps CrB b completes one full revolution every 417.9 Earth days (1.14Julian years) at a semi-major axis of 1.3 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 33.8 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.11 carries the world between 1.157 AU at periapsis and 1.443 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 854 K (+581°C / +1078°F) and receiving 101.70 S⊕ (~138,414 W/m²), eps CrB b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star eps CrB is classified as an orange K-type star of spectral type K2 III with an effective photospheric temperature of 4,406 K, a radius of 21 R☉, a mass of 1.7 M☉, an estimated bolometric luminosity of 149.11 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.74 Gyr and a metallicity of [Fe/H] = -0.094 dex (near-solar heavy-element abundance). From Earth, eps CrB shines at apparent V-band magnitude 4.126 (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 | eps CrB |
| Spectral Type | K2 III |
| Effective Temp (Teff) | 4,406 K |
| Stellar Radius | 21.0000 R☉ |
| Stellar Mass | 1.7000 M☉ |
| Bolometric Luminosity | 149.11 L☉ |
| Metallicity [Fe/H] | -0.094 dex |
| Stellar Age | 1.740 Gyr |
| Apparent Magnitude | V: 4.126 · G: 3.758 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 1.300000 AU |
| Orbital Period | 417.9 days |
| Mean Orbital Velocity | 33.8 km/s |
| Orbital Eccentricity (e) | 0.11000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 5.73 g/cm³ (144.8 km/s vesc) |
| Insolation Flux | 101.7001 S⊕ (~138,414 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 227.900 LY (69.868 pc) |