HD 114729 b
Astrophysical Synthesis & Habitability Characterization
HD 114729 b is a confirmed gas giant exoplanet orbiting the star HD 114729, located approximately 123.3 light-years (37.81 parsecs) from the Solar System. First announced in 2002 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 13.9 Earth radii (1.24 Jupiter radii) and has a measured mass of 262.21 Earth masses (0.83 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.54 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.36 g⊕ (13.34 m/s²), and an escape velocity of 48.6 km/s.
In its orbital architecture around HD 114729, HD 114729 b completes one full revolution every 1121.79 Earth days (3.07Julian years) at a semi-major axis of 2.067 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 20 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.079 carries the world between 1.9037 AU at periapsis and 2.2303 AU at apoapsis, driving measurable seasonal insolation cycles.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 13.900 R⊕, HD 114729 b 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 HD 114729 is classified as a solar-type yellow star of spectral type G0 V with an effective photospheric temperature of 5,844 K, a radius of 1.473 R☉, a mass of 0.936 M☉, an estimated bolometric luminosity of 2.271 L☉. Stellar evolution modeling indicates an estimated stellar age of 10.116 Gyr and a metallicity of [Fe/H] = -0.33 dex (metal-poor relative to the Sun). From Earth, HD 114729 shines at apparent V-band magnitude 6.68 (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 114729 |
| Spectral Type | G0 V |
| Effective Temp (Teff) | 5,844 K |
| Stellar Radius | 1.4730 R☉ |
| Stellar Mass | 0.9360 M☉ |
| Bolometric Luminosity | 2.271 L☉ |
| Metallicity [Fe/H] | -0.330 dex |
| Stellar Age | 10.116 Gyr |
| Apparent Magnitude | V: 6.680 · G: 6.514 |
| System Architecture | 2 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 2.067000 AU |
| Orbital Period | 1121.79 days |
| Mean Orbital Velocity | 20 km/s |
| Orbital Eccentricity (e) | 0.07900 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 0.54 g/cm³ (48.6 km/s vesc) |
| Insolation Flux | 0.6170 S⊕ (~840 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 123.300 LY (37.806 pc) |