BD-06 1339 c
Astrophysical Synthesis & Habitability Characterization
BD-06 1339 c is a confirmed gas giant exoplanet orbiting the star BD-06 1339, located approximately 66.1 light-years (20.27 parsecs) from the Solar System. First announced in 2013 by La Silla Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 8.38 Earth radii (0.75 Jupiter radii) and has a measured mass of 53 Earth masses (0.17 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.5 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.75 g⊕ (7.35 m/s²), and an escape velocity of 28.1 km/s.
In its orbital architecture around BD-06 1339, BD-06 1339 c completes one full revolution every 125.94 Earth days at a semi-major axis of 0.435 AU (situated at an orbital separation between Mercury's 0.39 AU and Venus's 0.72 AU). Its mean orbital velocity is approximately 37.6 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.31, swinging from 0.3002 AU at periapsis out to 0.5699 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 8.380 R⊕, BD-06 1339 c exceeds the empirical ~1.8–2.2 R⊕ Fulton radius valley threshold, indicating a substantial hydrogen-helium or supercritical volatile envelope without a conventional solid terrestrial surface.
The host star BD-06 1339 is classified as an orange K-type star of spectral type K7/M0 V with an effective photospheric temperature of 4,324 K, a radius of 0.6864 R☉, a mass of 0.7 M☉, an estimated bolometric luminosity of 0.148 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.4 Gyr and a metallicity of [Fe/H] = -0.14 dex (metal-poor relative to the Sun). From Earth, BD-06 1339 shines at apparent V-band magnitude 9.7 (accessible to binoculars and small amateur telescopes) in the Southern celestial hemisphere. The BD-06 1339 system is a multi-planet architecture hosting 2 confirmed worlds, with BD-06 1339 c sharing its stellar neighborhood alongside BD-06 1339 b.
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 | BD-06 1339 |
| Spectral Type | K7/M0 V |
| Effective Temp (Teff) | 4,324 K |
| Stellar Radius | 0.6864 R☉ |
| Stellar Mass | 0.7000 M☉ |
| Bolometric Luminosity | 0.148 L☉ |
| Metallicity [Fe/H] | -0.140 dex |
| Stellar Age | 4.400 Gyr |
| Apparent Magnitude | V: 9.700 · G: 9.107 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.435000 AU |
| Orbital Period | 125.94 days |
| Mean Orbital Velocity | 37.6 km/s |
| Orbital Eccentricity (e) | 0.31000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 0.5 g/cm³ (28.1 km/s vesc) |
| Insolation Flux | 0.5024 S⊕ (~684 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 66.100 LY (20.270 pc) |