HD 92788 b
Astrophysical Synthesis & Habitability Characterization
HD 92788 b is a confirmed gas giant exoplanet orbiting the star HD 92788, located approximately 113 light-years (34.65 parsecs) from the Solar System. First announced in 2000 by Multiple Observatories using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 13 Earth radii (1.16 Jupiter radii) and has a measured mass of 1195.041 Earth masses (3.76 Jupiter masses). Combining its mass and radius yields a mean bulk density of 3 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 7.07 g⊕ (69.33 m/s²), and an escape velocity of 107.2 km/s.
In its orbital architecture around HD 92788, HD 92788 b completes one full revolution every 325.803 Earth days at a semi-major axis of 0.97 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 32.4 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.35, swinging from 0.6305 AU at periapsis out to 1.3095 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 13.000 R⊕, HD 92788 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 92788 is classified as a solar-type yellow star of spectral type G6 V with an effective photospheric temperature of 5,744 K, a radius of 1.14 R☉, a mass of 1.15 M☉, an estimated bolometric luminosity of 1.269 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.55 Gyr and a metallicity of [Fe/H] = 0.27 dex (metal-rich relative to the Sun). From Earth, HD 92788 shines at apparent V-band magnitude 7.316 (accessible to binoculars and small amateur telescopes) in the Southern celestial hemisphere. The HD 92788 system is a multi-planet architecture hosting 2 confirmed worlds, with HD 92788 b sharing its stellar neighborhood alongside HD 92788 c.
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: Multiple Observatories · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 92788 |
| Spectral Type | G6 V |
| Effective Temp (Teff) | 5,744 K |
| Stellar Radius | 1.1400 R☉ |
| Stellar Mass | 1.1500 M☉ |
| Bolometric Luminosity | 1.269 L☉ |
| Metallicity [Fe/H] | 0.270 dex |
| Stellar Age | 2.550 Gyr |
| Apparent Magnitude | V: 7.316 · G: 7.139 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.970000 AU |
| Orbital Period | 325.803 days |
| Mean Orbital Velocity | 32.4 km/s |
| Orbital Eccentricity (e) | 0.35000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 3 g/cm³ (107.2 km/s vesc) |
| Insolation Flux | 1.1129 S⊕ (~1,515 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 113.000 LY (34.654 pc) |