HD 207832 b
Astrophysical Synthesis & Habitability Characterization
HD 207832 b is a confirmed gas giant exoplanet orbiting the star HD 207832, located approximately 192.2 light-years (58.93 parsecs) from the Solar System. First announced in 2012 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 14.2 Earth radii (1.27 Jupiter radii) and has a measured mass of 177.985 Earth masses (0.56 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.34 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.88 g⊕ (8.63 m/s²), and an escape velocity of 39.6 km/s.
In its orbital architecture around HD 207832, HD 207832 b completes one full revolution every 160.07 Earth days at a semi-major axis of 0.586 AU (situated at an orbital separation between Mercury's 0.39 AU and Venus's 0.72 AU). Its mean orbital velocity is approximately 39.8 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.197 carries the world between 0.4706 AU at periapsis and 0.7014 AU at apoapsis, driving measurable seasonal insolation cycles.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 14.200 R⊕, HD 207832 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 207832 is classified as a solar-type yellow star of spectral type G5 V with an effective photospheric temperature of 5,726 K, a radius of 0.89 R☉, a mass of 1.05 M☉, an estimated bolometric luminosity of 0.764 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.36 Gyr and a metallicity of [Fe/H] = 0.14 dex (metal-rich relative to the Sun). From Earth, HD 207832 shines at apparent V-band magnitude 8.78 (accessible to binoculars and small amateur telescopes) in the Southern celestial hemisphere. The HD 207832 system is a multi-planet architecture hosting 2 confirmed worlds, with HD 207832 b sharing its stellar neighborhood alongside HD 207832 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: W. M. Keck Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 207832 |
| Spectral Type | G5 V |
| Effective Temp (Teff) | 5,726 K |
| Stellar Radius | 0.8900 R☉ |
| Stellar Mass | 1.0500 M☉ |
| Bolometric Luminosity | 0.764 L☉ |
| Metallicity [Fe/H] | 0.140 dex |
| Stellar Age | 1.360 Gyr |
| Apparent Magnitude | V: 8.780 · G: 8.612 |
| System Architecture | 3 Stars, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.586000 AU |
| Orbital Period | 160.07 days |
| Mean Orbital Velocity | 39.8 km/s |
| Orbital Eccentricity (e) | 0.19700 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 0.34 g/cm³ (39.6 km/s vesc) |
| Insolation Flux | 2.2605 S⊕ (~3,077 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 192.200 LY (58.929 pc) |