24 Boo b
Astrophysical Synthesis & Habitability Characterization
24 Boo b is a confirmed gas giant exoplanet orbiting the star 24 Boo, located approximately 313.1 light-years (95.99 parsecs) from the Solar System. First announced in 2018 by Okayama Astrophysical 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 280.642 Earth masses (0.88 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.58 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.45 g⊕ (14.22 m/s²), and an escape velocity of 50.3 km/s.
In its orbital architecture around 24 Boo, 24 Boo b completes one full revolution every 30.33 Earth days at a semi-major axis of 0.194 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 69.6 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.032 (ranging from 0.1878 AU at periapsis to 0.2002 AU at apoapsis), the planet experiences minimal orbital distance variation.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1841 K (+1568°C / +2854°F) and receiving 2,001.28 S⊕ (~2,723,736 W/m²), 24 Boo b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star 24 Boo is classified as a solar-type yellow star of spectral type G3 IV with an effective photospheric temperature of 4,816 K, a radius of 12.19 R☉, a mass of 1.05 M☉, an estimated bolometric luminosity of 71.72 L☉. Stellar evolution modeling indicates an estimated stellar age of 6.92 Gyr and a metallicity of [Fe/H] = -0.78 dex (metal-poor relative to the Sun). From Earth, 24 Boo shines at apparent V-band magnitude 5.59 (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: Okayama Astrophysical Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | 24 Boo |
| Spectral Type | G3 IV |
| Effective Temp (Teff) | 4,816 K |
| Stellar Radius | 12.1900 R☉ |
| Stellar Mass | 1.0500 M☉ |
| Bolometric Luminosity | 71.72 L☉ |
| Metallicity [Fe/H] | -0.780 dex |
| Stellar Age | 6.920 Gyr |
| Apparent Magnitude | V: 5.590 · G: 5.334 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.194000 AU |
| Orbital Period | 30.33 days |
| Mean Orbital Velocity | 69.6 km/s |
| Orbital Eccentricity (e) | 0.03200 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 0.58 g/cm³ (50.3 km/s vesc) |
| Insolation Flux | 2001.2754 S⊕ (~2,723,736 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 313.100 LY (95.986 pc) |